Project Updates

24 Mar 2020 - Daily UAF science summary for ICEX operations

Posted 1745h ADT 24 Mar

NOAA GFS continues to forecast moderate winds of 20-25 mph for tomorrow (March 25^th). There is a chance of light snow (<0.5”) in the morning, but blowing snow through the day is likely given the sustained wind speeds.

Winds on March 26^th and 27^th are expected to be relatively light (≤15 mph) and from the north-to-west quadrant. On March 28^th, a strong pressure gradient is forecasted to develop across Alaska with a 980 mb Low in the Gulf of Alaska and 1040 mb High over the North Slope which will produce at least moderate winds of 20-25 mph over the camp.

A strong Low (~970 mb) enters the East Siberian Sea late on March 29^th. As it tracks toward the Central Arctic over the following 2-3 days it will force a southerly wind regime and above-normal air temperatures across the west Arctic.

UAF analog forecasts have a slightly better handle on the synoptic pattern compared to yesterday, but still are struggling with the development of the surface high pressure indicated by all the global models. The transition from low to high pressure in the Chukchi Sea apparently evolves in enough different ways to "confuse" the analogs analysis. That said, the point forecast for SLP at the ICEX camp location mirrors the NOAA GFS fairly closely.

The southern Beaufort Sea was mostly covered by clouds today but there was a large opening north of Prudhoe Bay, and leads could be seen through the clouds north of Barter Island and in the vicinity of Camp Seadragon. The pack ice north of Prudhoe Bay appears to be predominantly discrete floes, separated by open water or thin ice. In contrast, the leads are long, continuous cracks, suggesting that they propagated through a relatively continuous ice cover by connecting lines of weakness. Since the area of the leads was cloudy yesterday, it isn’t possible to estimate their age. There were no additional breaks in the ice cover visible further to the east.

Day-by-day

Day 1 (Mar 25): WNW winds of 20-25 mph; a chance of light snow early in the day; blowing snow

Day 2 (Mar 26): Northerly winds of 10-15 mph; A 1033 mb High moves into the Chukchi

Day 3 (Mar 27): Light northwest to west winds; High pressure continues over the Chukchi; a 988 mb Low sets up over SW AK

Day 4 (Mar 28): Northwesterly to westerly winds of 20-25 mph over the camp; clear skies; a strong pressure gradient between the 980 mb Low in the Gulf of AK and 1040 mb High over the North Slope

Day 5 (Mar 29): Weak winds strengthening out of the south late in the day; a strong Low (970 mb) enters the East Siberian Sea

Day 6 (Mar 30): Moderate southerly winds; the Low deepens to 957 mb in the early evening as it moves toward the Central Arctic

Day 7 (Mar 31): Moderate southerly winds continue; the Low weakens through the day as it continues toward the Central Arctic

Day 8 (Apr 1): Southwesterly-to-southerly winds continue; the Low moves toward the Atlantic sector; a weak Low moves over the North Slope late in the day

• John Walsh, Brian Brettschneider, Lew Shapiro, Uma Bhatt, Tom Ballinger, Jackie Richter-Menge, Hajo Eicken.

23 Mar 2020 - Daily UAF science summary for ICEX operations

Posted 1630h ADT 23 Mar

Consistent with the NOAA GFS runs of previous days, sustained winds will range from 15-25 mph over the next two days and are associated with successive cyclones passing across the Beaufort Sea. Tomorrow (March 24^th), winds are anticipated to shift from the southeast to west and increase to 15-20 mph in the afternoon with evening gusts to 35 mph possible. New snow of ~1” is possible over the camp, while larger amounts continue to be forecasted toward interior Alaska.

Winds on March 25^thare forecasted to be 20-25 mph with blowing snow possible. Weather conditions thereafter, particularly during the day, appear relatively benign through month’s end with weak winds and several days of high pressure over the Beaufort or Chukchi Sea.

With a very unusual pattern developing, the UAF Analog models did not capture the developing high pressure in the Chukchi Sea well. Most of the best matches occurred in the 1940s, 1950s, and 1960s, with little useful guidance for ice cover and weather pattern evolution.

The southern Beaufort Sea has been cloudy all day with only a small break where the pack ice could be seen. As a result, there is no new information on the state of the pack ice.

Day-by-day

Day 1 (Mar 24): Southeasterly shifting to westerly winds, increasing to 15-20 mph in the afternoon; gusts to 35 mph at night; new snowfall of ~1” possible; above-normal air temperatures (daytime high 16F); a Low moves across the Beaufort

Day 2 (Mar 25): Westerly winds increasing in the late morning to 20-25 mph; chance of blowing snow; another Low moves across the Beaufort

Day 3 (Mar 26): Northerly winds, weakening through the morning; a 1036 mb High moves into the northern Chukchi

Day 4 (Mar 27): Weak easterly winds shifting to the west and strengthening late in the day; a strong pressure gradient sets up with a 988 mb Low over SW AK and a 1034 mb High in the Chukchi

Day 5 (Mar 28): Moderate westerly winds early, decreasing in the afternoon; high pressure moves into the Beaufort

Day 6 (Mar 29): Weak winds; clear skies

Day 7 (Mar 30): Southerly to southwesterly winds; a Low moves into the central Arctic

Day 8 (Mar 31): Weak winds; clear skies; high pressure over the Beaufort

• John Walsh, Brian Brettschneider, Lew Shapiro, Uma Bhatt, Tom Ballinger, Jackie Richter-Menge, Hajo Eicken.

22 Mar 2020 - Daily UAF science summary for ICEX operations

Posted 1630h ADT 22 Mar

The forecast from yesterday is largely on track: no major high-wind events predicted over the next 10 days, with the only unsettled period at the onset (Days 1 and 2).

NOAA GFS continues to forecast establishment of a Beaufort High, which moves east from the Chukchi Sea during Days 4-7. (Recent model runs differ on whether this High exits the region on Day 8 or remains over the Beaufort/Chukchi Seas through Day 10). Under either scenario, clear skies and light winds should dominate during the second half of this week. Temperatures will turn colder by mid-week and remain colder than during the past week.

The global models are now all in agreement on building a massive surface high pressure (conforming with the climatological Beaufort High) around 500 miles north of Point Barrow by Day 4-5. The CMC, UKMET, NOAA GFS, and ECMWF models all agree on this high pressure solution, with UKMET and ECMWF having the high centered more toward the Chukchi Sea.

The UAF analog predictions have a strong handle on the upper level features; e.g., the 500 mb ridge finally moving from west to east along the southern portion of the Mainland. Unlike the upper level pattern, the analogs are less aligned with respect to the surface features. The abrupt pattern change from wave after wave of low pressure to a high pressure regime is something that analogs often do not handle well. That said, for the point location of the ICEX camp, the analogs ensemble of the top 5 matches shows an SLP of 1027 mb at Day 5 while the GFS has a pressure of 1032 mb. The analogs generally capture the pattern of pressure drops through Day 3 and big pressure increases through Day 5. The interpretation of this is that the top analogs have correctly identified the changing pattern, but the top 50 analogs used to generate the animations have not.

Today we got our first clear look at the pack ice off the North Slope and have obtained satellite images over the past 6 hours. During this period, the pack was drifting generally toward the ESE, although it has slowed in the last hour or two. The number of identifiable markers decreases east of the longitude of Barter Island, because the pack ice is being compressed against the coast in that direction. Some of the leads connecting identifiable markers also appeared to close over the period of observation as the pack ice slowed as it was compressed against the coast.

The most rapid motion, and the most obvious deformation occurred within about 50 NM of the coast. Floes drifting across Camden Bay were jammed against the coast at Barter Island and created a bottleneck. Further east, an arch developed at Herschel Island and pack ice further east broke into floes and was pushed by winds (visible as cloud streets at the surface) into an apparent space off the Mackenzie Delta.

Day-by-day

Day 1 Mon Mar 23 Winds from southwest to south, 5-15 mph; light snow late, mainly to south

Day 2 Tue Mar 24 Weak low (996 mb) passes by, light winds from south shifting to westerly; light snow (about an inch)

Day 3 Wed Mar 25 Westerly winds, 10-20 mph; Low pressure moving off to east (Banks I.)

Day 4 Thu Mar 26 Light northwesterly winds (10-15 mph); colder; High pressure moves into Chukchi Sea from the west

Day 5 Fri Mar 27 Light northwesterly winds (5-15 mph); 1034 mb High over Chukchi

Day 6 Sat Mar 28 Light northwest winds, 1028 mb High north of Barrow; clear skies

Day 7 Sun Mar 29 Light winds, 1024 mb High over Beaufort Sea; “ “

Day 8 Mon Mar 30 Light easterly winds, 1026 mb High moves southeast of Beaufort Sea

Day 9 Tue Mar 31 Light easterly winds; weak Low pressure systems over southern Alaska

Day 10 Wed Apr 1 Light easterly winds; High pressure (1031 mb) to north near 80°N

• John Walsh, Brian Brettschneider, Lew Shapiro, Uma Bhatt, Tom Ballinger, Jackie Richter-Menge, Hajo Eicken.

21 Mar 2020 - Daily UAF science summary for ICEX operations

Posted 1700h ADT 21 Mar

With a shift of the storm track to the South over the next 10 days, the ICEX camp area will transition from the recent windy/snowy pattern to a more benign pattern with lighter winds and less snow. In the near term, Day 1 (Sunday 22 March) is forecast to have brisk (15-20 mph) westerly winds, followed by lighter winds but some light snow Monday into Tuesday. The remainder of the week is forecast to be largely free of new snow.

NOAA GFS predicts for the classic Beaufort High pressure center to reappear by Day 4 and 5 (Wed/Th March 25/26). The ECMWF model does not support that solution. While climatology favors the Beaufort High, the European ECMWF and Canadian CMC model both predict strong low pressure just north of the Mackenzie River.

The UAF analog forecasts have a solid handle on the synoptic pattern. For the first time in a number of days, late February 2015 is no longer a top analogs match with the regional SLP field. All but one of the new top matches (4/9/62, 4/7/48, 3/28,2019, 3/21/54, and 3/16/93) are for a point in the season after today's date. This indicates the pattern is more representative of a pattern later in the season. Following those five days, there is a marked reduction in winds by 48 hours that lasts through the remaining 5 days. This wind forecast is remarkably consistent with today's 12 UTC NOAA GFS forecast – which shows light winds from 48-120 hours.

A NOAA VIIRS satellite image from earlier today (15:40 UTC) showed the only clear area along the coast of the North Slope. Camp Seadragon was under clouds north of the clear area. There was plenty of “open water/thin ice” visible in the clear area. A later image (18:57 UTC) shows an area about 120 NM north of the coast where the pack ice has the characteristics of an early stage of breakup with leads breaking the ice into large angular floes.

Further east than the image in the poster covers, the pack ice was compressed against the coast SW of Tuk Point and the ice in the mouth of Amundsen Gulf, and the ice cover was more intact with longer leads and fewer openings.

Day-by-day

Day 1 Sun Mar 22 West winds, 15-20 mph; little or no new snow

Day 2 Mon Mar 23 Light winds from west; light snow (less than an inch; more inland)

Day 3 Tue Mar 24 Light winds, variable direction; light snow (about an inch, more inland)

Day 4 Wed Mar 25 Light winds variable direction; little or no snow (snow inland)

Day 5 Thu Mar 26 Light winds from north, shifting to easterly, increasing, 10-20 mph at night

Day 6 Fri Mar 27 Winds from east, moderate speeds of 10-20 mph; no snow

Day 7 Sat Mar 28 Winds from east, 10-20 mph; clear skies; Beaufort High to north

Day 8 Sun Mar 29 Winds from east, 10-15 mph, High pressure to north “

Day 9 Mon Mar 30 Winds from east, 10-15 mph, “

Day 10 Tue Mar 31 Winds from east, 10-15 mph, “

• John Walsh, Brian Brettschneider, Lew Shapiro, Uma Bhatt, Tom Ballinger, Jackie Richter-Menge, Hajo Eicken.

20 Mar 2020 - Daily UAF science summary for ICEX operations

Posted 1730h ADT 20 Mar

The NOAA GFS model runs remain consistent with previous days regarding tomorrow’s forecast for moderate winds (15-20 mph) with gusts to 25 mph and a chance of blowing snow. Light snow (<0.5”) is also possible after 4pm according to the NWS point forecast.

Strong westerly winds of 20-25 mph, gusting to 30 mph, with blowing snow is forecasted for March 22^nd. Light-to-moderate southwesterly winds (10-15 mph) return on March 23^rd, but new snowfall of 1-2” and blowing snow may limit visibility.

Consistent with yesterday’s GFS model runs, weak (though shifting) winds and relatively benign weather conditions are forecasted for Tuesday to Friday (March 24-27) next week that look to be conducive to wrapping up the camp demobilization effort.

UAF analog forecasts have a solid handle on the synoptic pattern. Once again, Feb (27), 2015, was the best analog. An animation of sea level pressures and wind speeds from Feb 24 through Mar 4, 2015 (see animations on webpage) indicates a strong ridge of high pressure developing over the southwest mainland with occasional areas of low pressure dropping from the high Arctic over the top of the upper ridge into the northern Beaufort Sea and to near Banks island.

The analogs ensemble has a very strong signal for a massive upper level high pressure intensifying and retrograding over the Alaska Peninsula. An upper trough develops north of the Beaufort Sea by 48 hours according to all global dynamic models. There is strong agreement with this scenario according to the historical analogs. As was the case yesterday, there is a strong analogs signal for temperatures to drop throughout the five day forecast period. This is nearly identical to the NOAA GFS forecast and the NWS forecast for Deadhorse. Before the temperature drop occurs, strong SW winds with blowing snow are indicated by the analogs and the dynamical forecasts.

Day-by-day

Day 1 (Mar 21): Southwesterly winds at 15-20 mph during the day; gusts to 25 mph; blowing snow before 4p; chance of light snow (<0.5”) after 4p

Day 2 (Mar 22): Westerly winds of 20-25 mph; gusts to 30 mph; blowing snow likely

Day 3 (Mar 23): Light southwesterly winds of 10-15 mph shifting to northerly later in the day; blowing snow; chance of snow (1-2”); a 1041 mb High moves onto southwestern AK

Day 4 (Mar 24): Light northerly winds of 10-15 mph becoming westerly late; A High moves into the southern Beaufort

Day 5 (Mar 25): Light southerly winds; a weak Low moves across the North Slope

Day 6 (Mar 26): Light southerly winds shifting to westerly by nightfall; a weak Low enters the Beaufort

Day 7 (Mar 27): Light northeasterly winds turning easterly; a 980 mb Low enters the Chukchi late in the day

Day 8 (Mar 28): Strong easterly winds; the Low tracks along the North Slope

Day 9 (Mar 29): Continued strong easterly winds through the day

Day 10 (Mar 30): Strong winds from the east continue early in the day

• John Walsh, Brian Brettschneider, Lew Shapiro, Uma Bhatt, Tom Ballinger, Jackie Richter-Menge, Hajo Eicken.

19 Mar 2020 - Daily UAF science summary for ICEX operations

Posted 1715h ADT 19 Mar

Moderate-to-strong winds over the next four days (March 20-23) will create periods of blowing snow conditions. During tomorrow (March 20), southwesterly winds of 15-20 mph are expected through late morning before strengthening to 20-30 mph in the afternoon. The daytime high of 29F has been consistent in the NWS point forecast over the last two days. Gusts tomorrow night up to ~45 mph are possible. Light snow (<1”) is expected. NWS Fairbanks has issued a blizzard warning from 10a (March 20) to 7a (March 21), noting “difficult to impossible” travel conditions between blowing snow and some fresh snowfall.

As the blizzard conditions subside, the forecast for March 21^st looks favorable, and, relative to the next four days (March 20-23), will have the lightest winds in the afternoon (10-15 mph). NWS is calling for “possible” blowing snow between 7a and 1p.

Strong winds return on March 22^nd, shifting between the northwest and southwest directions as a High sets up over southwestern AK. High pressure and northerly-to-westerly winds over the Beaufort Sea are forecasted for March 23-27.

UAF analog forecasts have a solid handle on the synoptic pattern. Once again, the analogs have identified February 25-26, 2015, as a high quality match. This date has been a match on nearly every day for the last 10 days. This gives excellent confidence that current pattern evolution was captured well by the Feb 25 analog. Using that analog only, the progression from Day 0 is for low pressure near Wrangel Island to move 500 miles north of Pt. Barrow to north of Banks Island by 48-60 hours. After that, strong high pressure developed over southwestern Alaska with a new low pressure north of Demarcation Point became established. This solution is remarkably similar to today's 12 UTC GFS solution.

Looking at a composite of the winds from the top 5 analogs, we see a fluctuation between moderate southwest winds, followed by a period of lower, variable winds. This is a solution that the global models support. The 2-meter temperature forecast from the analogs and the NOAA GFS are nearly exactly the same. The same is true of the upper level (500 mb) forecast. Overall, there is excellent agreement between the numerical guidance and the analogs. This gives confidence that the numerical guidance has high levels of predictability.

The entire area between Wrangel Island and Barter Island has been cloud covered all day with the exception of a break in the clouds north of Prudhoe Bay. That area is shown in the satellite scene for today to illustrate the difference in the degree of pack ice deformation with distance offshore. Some floes nearest to the coast have been broken more than once and reduced in size, while further offshore, the leads are widely spaced and small floes are only present as fragments in the wider leads.

Day-by-day

Day 1 (Mar 20): Southwesterly winds increasing to 20-30 mph by afternoon; gusts overnight to 45 mph; blowing snow; a chance of light snowfall (<1”) in the afternoon; much warmer-than-normal during the day (daytime high 29F)

Day 2 (Mar 21): Westerly winds 10-15 mph; strengthening to 20 mph late around nightfall; blowing snow

Day 3 (Mar 22): Northwesterly winds of 20-30 mph shifting to southwesterly and weakening late in the day; 1046 mb High enters southwestern AK

Day 4 (Mar 23): Northwesterly winds of 15-20 mph; one high pressure cell over AK and another moves north of Utqiagvik late in the day; chance of snow mid-to-late morning

Day 5 (Mar 24): Weak northwesterly to westerly winds; the high moves eastward into northern Canada

Day 6 (Mar 25): Weak winds early, strengthening out of the northeast; a High moves into the Chukchi late

Day 7 (Mar 26): Northerly to northwesterly winds, strengthening late; frigid temperatures; a strong pressure gradient with a 1045 mb High over the North Slope and 983 mb Low over southeast AK

Day 8 (Mar 27): Weak northwesterly winds becoming southerly; a High moving south from the Beaufort to northern Yukon

Day 9 (Mar 28): Moderate southerly winds; a Low moving into the northern Beaufort

Day 10 (Mar 29): Weak southerly winds

• John Walsh, Brian Brettschneider, Lew Shapiro, Uma Bhatt, Tom Ballinger, Jackie Richter-Menge, Hajo Eicken.

18 Mar 2020 - Daily UAF science summary for ICEX operations

Posted 1830h ADT 18 Mar

Two more low pressure systems will affect the Beaufort Sea through the next five days, maintaining the unsettled and generally windy pattern that has prevailed recently. Beginning around Day 6, a pattern change appears to be in the offing: Low pressure centers are forecast to track farther south over Alaska and, by Days 7 or 8, high pressure starts to develop north of Alaska. This could be the long-awaited return of the Beaufort High.

The NOAA GFS and NAM (North American Model) are quite consistent in depicting a 983 mb Low in the Chukchi Sea with a moderately strong pressure gradient over the Beaufort Sea on Day 1 (tomorrow). This pressure gradient wind would support sustained surface winds of 20 mph or higher. By contrast, the forecast from the Fleet Weather model indicates higher pressure, lighter winds, and more favorable conditions over the southern Beaufort.

The UAF analog forecast captures the synoptic pattern, with very strong signal for higher than normal air pressure over the Mainland (although not as high as a week or two ago) and low pressure over the Chukchi Sea and Beaufort Seas. This is a continuation of the pattern that began late last week. These types of patterns often have a series of 2-4 storms that take a similar track. The last storm is frequently the strongest.

The Chukchi and Beaufort Seas are currently experiencing the highest temperature anomalies anywhere on the globe. Temperatures of 25°F above normal cover the entire ocean area north of Alaska. The analogs have captured this feature and the evolution of temperature anomalies over the next five days. While the NOAA GFS forecast keeps temperatures in the 10Fs, the top five analogs point to temperatures near 0F by Day 5; however, the 50-analog ensemble has a stronger warm signal.

The Beaufort Sea is almost completely cloud covered. The few locations where the surface is visible show evidence of ice movement toward the north. Given the state of the pack ice over the past few days, there are ample places for leads to originate and keep the pack loose enough to move in response to wind forces.

Day-by-day

Day 1 Thu Mar 19: Southwesterly winds, 20-30 mph, blowing snow, light new snow; 983 mb Low north of Barrow

Day 2 Fri Mar 20: Continued southwesterly winds, 20-30 mph, blowing snow; 985 mb Low north of Banks Island

Day 3 Sat Mar 21: Winds slacken to 10-15 mph, still from the southwest

Day 4 Sun Mar 22: Westerly winds, 20-30 mph; 1045 mb High builds into southwest AK, 1007 mb Low enters Chukchi Sea

Day 5 Mon Mar 23: Low pressure trough passes over ICEX area; light snow; moderate SW winds shifting to westerly

Day 6 Tue Mar 24: Winds shift to light easterly as weak Low tracks over or just south of northern Alaska coast; weak High pressure to northwest

Day 7 Wed Mar 25: Weal high pressure ridge over eastern Beaufort Sea; light winds and clear skies likely

Day 8 Thu Mar 26: Another Low pressure center tracks eastward south of the northern Alaska coast; weak high pressure to the north; easterly to northeasterly winds

Day 9 Fri Mar 27: High pressure builds over the northern Chukchi Sea; northeasterly winds over Beaufort region

Day 10 Sat Mar 28: Light northwesterly winds, clear skies; 1036 mb High several hundred miles north of Barrow, nearly stationary -- the Beaufort High finally returns ?

• John Walsh, Brian Brettschneider, Lew Shapiro, Uma Bhatt, Tom Ballinger, Jackie Richter-Menge, Hajo Eicken.

17 Mar 2020 - Daily UAF science summary for ICEX operations

Posted 1645h ADT 17 Mar

The latest NOAA 20 image has thin cloud cover but is clear enough to show that there have probably been new leads and small openings created in the pack ice since yesterday. There are now many lines and zones of weakness in the pack ice such that shifts in the direction of ice drift will result in even more crack and lead formation.

With the NOAA GFS forecast showing the active pattern of storm systems with wind and snow to continue, in coming days the likelihood for formation of new cracks and leads is high and will require monitoring of the Camp floe and runway.

The UAF analog forecast has a reasonable handle on the large-scale features. As previously noted, when a high pressure regime over the Mainland breaks down with a storm storm moving through western Alaska and the Bering Sea, it is usually followed by 2-4 more storms with a similar path. The NOAA GFS forecast confirms this pattern with a parade of storms lined up to move across western Alaska and then the Arctic waters.

Thursday March 19th is forecasted to have the lightest winds (S at 15-20 mph according to the NWS point forecast) of the next three days until another relatively light wind day anticipated on Saturday March 21st and possibly Sunday March 22nd.

Another storm system Sunday-Monday is forecast to track close to the camp, although much weaker than in yesterday’s model runs. During days 7-10 (Tues-Fri), NOAA GFS forecasts have large uncertainty. On Day 7 a Low is forecast to track into mainland Alaska from the Bering Strait region (an unusual track), followed by a cessation of the progressive storm pattern.

Day-by-day

Day 1, Wed Mar 18: 982 mb L pressure centered several hundred miles north of Barrow; southwesterly winds 20-30 mph; light snow (an inch or so), blowing snow

Day 2, Thu Mar 19: Continued brisk southwesterly winds as next Low moves across Chukchi

Day 3, Fri Mar 20: Continued brisk southwesterly winds as Low moves off to the northeast of ICEX area; light snow late

Day 4, Sat Mar 21: Winds slacken somewhat to light westerly (good window of opportunity)

Day 5, Sun Mar 22: Next Low moves across Chukchi Sea, with winds shifting to southern quadrant; snow late

Day 6, Mon Mar 23: Westerly winds on back side of Low; blowing snow possible again

Day 7, Tue Mar 24: Another reprieve as winds slacken; GFS tracks next Low eastward into mainland Alaska (forecast path of Low varies in recent model runs)

Day 8, Wed Mar 25: High pressure center moves into Beaufort Sea; light northwesterly winds

Day 9, Thu Mar 26: Weak High over Beaufort, weak Low over Chukchi; light east winds

Day 10, Fri Mar 27: Continuation of pattern in Day 9

• John Walsh, Brian Brettschneider, Lew Shapiro, Uma Bhatt, Tom Ballinger, Jackie Richter-Menge, Hajo Eicken.

16 Mar 2020 - Daily UAF science summary for ICEX operations

Posted 1715h ADT 16 Mar

An active pattern of eastward progressing cyclones is forecasted to continue over at least the next week. As a result, southerly to westerly winds are expected to persist over the camp with periods of stronger winds over the next couple of days.

Tomorrow (March 17th) will see southeasterly winds increasing through the day to 20-25 mph by nightfall. Gusts could reach 35+ mph and, coupled with blowing snow, will likely act to reduce visibility. Wednesday (March 18th) will similarly see brisk southwesterly winds to 15-20 mph with higher gusts. Light snow (a new inch or so) and blowing snow will likely limit visibility.

According to NWS marine point forecast for the camp, Wednesday to Friday (March 18-20) air temperatures are anticipated to be much warmer than average with daytime highs in the upper teens to mid-20s.

For the UAF analog forecast, the analogs had a reasonable handle on the large-scale features. The pattern of higher pressure over the mainland and lower pressure north of the coast continues. Unlike the first few weeks of ICEX, the pressure gradient and isobar orientation makes for breezy southwest and southerly winds. The top sealevel pressure analogs are mostly similar to those identified yesterday (3/24/96, 2/26/2015, 4/7/89, 3/12/67, and 3/4/2018). The 2018 match is interesting because that was during the first week of ICEX 2018. Accordingly, the matches with the 2016 breakup events are now in the 20% to 30% range.

Satellite images, while obscured by clouds, show that the coastal sea ice shear zone now extends all along the North Slope from Point Barrow to Herschel Island, so the pack ice is separated from the landfast ice over that distance.

Day-by-day

Day 1 (Mar 17): Moderate winds from the southeast intensifying to 20-25 mph by early evening (3z); gusts to 35 mph; blowing snow

Day 2 (Mar 18): WSW winds of 15-20 mph; gusts to 30 mph; light snow early, probably about an inch; above-normal temperatures; a weak ridge builds in the Beaufort Sea

Day 3 (Mar 19): Moderate southerly to southwesterly winds sustained at 10-15 mph; a low moves just northeast from Wrangel Island; above-normal temperatures

Day 4 (Mar 20): Moderate southwesterly flow of 15-20 mph; continued mild temperatures

Day 5 (Mar 21): Westerly winds as a low-pressure trough passes to the north; some light snow possible with the trough passage; a high-pressure cell moves into southwestern AK

Day 6 (Mar 22): Southwesterly winds as another low moves eastward past Barrow and into the Beaufort Sea; increasing southwest winds and increasing chance of snow late in day and at night

Day 7 (Mar 23): Strong southwesterly-to-westerly winds weakening through the day

Day 8 (Mar 24): Another low enters the Beaufort Sea, with brisk southwesterly-to-westerly winds and snow

Day 9 (Mar 25): A break in the winds as the next Low appears near Wrangell Island

Day 10 (Mar 26): Yet another storm moves eastward across the Beaufort. The GFS shows this to be a strong one (968 mb), but the intensity will likely be moderated in future model runs.

• John Walsh, Brian Brettschneider, Lew Shapiro, Uma Bhatt, Tom Ballinger, Jackie Richter-Menge, Hajo Eicken.

15 Mar 2020 - Daily UAF science summary for ICEX operations

Posted 1730h ADT 15 Mar

The NOAA GFS forecast continues to show an active week of storm activity across the western Arctic with persistent above-normal air temperatures and southerly-to-westerly winds at the camp. Light to moderate snowfall (1-2”) is expected at the camp tomorrow (March 16th) between 12 and 18z followed by an increase in winds during the afternoon to 25-30 mph which may obscure visibility with blowing possible snow late in the day.

Cyclones entering the west Arctic on March 17thand 19th will propagate the pattern of southerly becoming westerly flow as these systems pass north of the camp heading eastward. The March 19th low-pressure system is associated with a 987 mb low just northeast of Wrangel Island (21z), though its central pressure has weakened in recent forecast runs.

The persistent absence of the climatological Beaufort High (corresponding to an anomalously positive and persistent Arctic Oscillation) is predicted to continue for at least the next 1-2 weeks. As a consequence, winds from the easterly sector will continue to be absent.

The absence of such easterly winds (and the lack of a Beaufort High) helps confine the ice pack in the eastern Beaufort Sea. This is confirmed by NOAA 20 imagery from today that shows no large lead systems formed during the most recent storm. However, the storm left numerous small openings scattered throughout the pack ice in the area of Camp Seadragon. Any of these could provide a site where new leads could form or extend when the wind shifts.

The most recent NOAA subseasonal-seasonal forecast (CFSv2) forecast from March 7-9 provided 12 ensembles to construct the outlook for March 21 and March 22. A low pressure in the north Pacific strengthens and moves westward from the 21st to the 22nd of March. Ensemble averaged wind maps suggest winds greater than 5 meters per second (> ~ 10 knots) in the ICEX region on Saturday and Sunday.

The UAF analog forecasts had a reasonable handle on the large-scale features. Looking at a composite of the top SLP analogs (4/5/1989, 3/17/1993, 2/26/2015, 3/22/1954, and 3/29/2019, we can construct a 5-day forecast of expected winds. This technique continues to show winds up to 20 mph for the next two days from the southwest before relaxing for two days, and then picking up again on Day 5.

Note: the ECMWF and NOAA GFS forecasts both develop a weak low pressure near the camp at Day 3, but the ECMWF maintains southwest winds at 20-25 mph in the vicinity of the ICEX camp nearly continuously for the next 5 days.

As always, the pattern of high pressure over the Mainland with lower pressures in the Arctic waters are poor matches with previous ICEX years.

Day-by-day

Day 1 (Mar 16): Moderate southerly winds becoming westerly and increasing to 25-30 mph by afternoon as a cyclone moves north of camp; above-average temperatures; light to moderate snowfall early-to-mid-morning; blowing snow late

Day 2 (Mar 17): Light winds, strengthening from the southeast to 15-20 mph late in the day; a low enters the west Arctic Ocean; above-average air temperatures

Day 3 (Mar 18): Moderate southeasterly winds becoming westerly; cyclone moves off into the central Arctic; warm air temperatures

Day 4 (Mar 19): Westerly winds increasing from the south; a 987 mb low passes just northeast of Wrangel Island; continued above-normal air temperatures

Day 5 (Mar 20): Moderate southwesterly winds as a cyclone passes north of camp; possible late morning snow shower

Day 6 (Mar 21): Moderate westerly winds of 15-20 mph; warmer-than-average temperatures

Day 7 (Mar 22): Strong southwesterly winds with a cyclone moving north of the camp

Day 8 (Mar 23): Another low entering the Chukchi Sea with moderate southeasterly winds becoming southwesterly late in the day; possible light snowfall

Day 9 (Mar 24): Strong southwesterly becoming westerly winds with the low moving over the Canadian Archipelago

Day 10 (Mar 25): Light winds early in the day

• John Walsh, Brian Brettschneider, Lew Shapiro, Uma Bhatt, Tom Ballinger, Jackie Richter-Menge, Hajo Eicken.

14 Mar 2020 - Daily UAF science summary for ICEX operations

Posted 1645h ADT 14 Mar

The pack ice along the North Slope from Point Barrow eastward past Harrison Bay has been broken up and shifted offshore, leaving irregularly shaped areas of open water between fragmented floes. East of Harrison Bay, the pack ice is tighter, and openings are smaller and more widely spaced. A notable point is that there are no long leads in the pack ice between Barter Island and the approximate location of Seadragon. Deformation of the pack ice then probably involved jostling and grinding between floes in a compressive environment, with this most recent storm impacting ice closely packed against the coast prior. Cloud cover is still continuous east of Demarcation Point and until that clears, we will not have a complete picture of changes in the ice from the storm (beyond cracks visible in Radarsat SAR imagery).

A succession of low pressure systems are forecast over the next 10 days. The first two of these will affect the ICEX area Sunday night and mid-week with light snow and moderate winds, although with much less intensity than the most recent system. Sunday will experience the lowest wind speeds, averaging 10-15 mph. Winds predicted to pick up to 15-30 mph Monday afternoon. Forecasts diverge between models late in the week, but some indication for another major storm system similar to the most recent storm moving into the ICEX area starting next weekend.

These subsequent storms may help open up the ice pack at Camp Seadragon enough to allow for incremental opening of leads and floe fragmentation.

Temperatures will generally be above-normal during the next 10 days. The remarkable absence of the Beaufort High and its easterly winds continues.

In the continued absence of the climatological Beaufort High, the pattern of high pressure over the Mainland with lower pressures in the Arctic waters are poor matches with previous ICEX years, reducing the predictive skill of the UAF analog forecasts.

Day-to-day

Day 1, March 15: Winds southwesterly shifting to southeasterly, averaging 10-15 mph

Day 2, March 16: Light snow in the a.m. as a low-pressure trough passes to the north; winds shift to westerly, 15-30 mph in afternoon, some blowing/drifting snow likely

Day 3, March 17: Winds become more southerly to southeasterly, moderate speeds; next Low moves north of Chukchi

Day 4, March 18: Southeasterly winds strengthen; light snow moves in as Low tracks well to the north of ICEX area; increased potential for blowing snow

Day 5, March 19: Lighter winds, generally southerly; next Low approaches Chukchi from west

Day 6, March 20: Low moves over or just north of ICEX; southwest winds, light snow

Day 7, March 21: Westerly or northwesterly winds, light snow

Day 8, March 22: Next low approaches Chukchi from west; High pressure to south; increasing southerly winds

Day 9, March 23: Low pressure system moved just north of ICEX area, followed by brisk west winds; snow and blowing snow

Day 10, March 24: West to northwest winds; Low pressure centered to east

• John Walsh, Brian Brettschneider, Lew Shapiro, Uma Bhatt, Tom Ballinger, Jackie Richter-Menge, Hajo Eicken.

13 Mar 2020 - Daily UAF science summary for ICEX operations

Posted 1700h ADT 13 Mar

The NOAA GFS forecast indicates that the strong southwesterly winds associated with the present storm will slowly wind down by early Sunday. After the present storm, the next ten days will see a series of weaker low pressure systems tracking to the west and north of the ICEX area; these will bring several periods of light snow, but not the extreme winds that accompanied the present system. Warmer-than-normal temperatures should prevail through the next 10-12 days. More detail on wind and blowing snow conditions provided in the day-by-day summary below.

As noted yesterday, the excellent surface and upper level UAF analog forecast match from Feb 25, 2015, had strong southwest winds for Deadhorse for nearly 60 hours. The March 26, 1996, and March 10, 1989, events saw strong winds at Deadhorse for only 24 hours. Using a composite of the top analogs matches, winds in the vicinity of the location of this year’s camp stayed in the 20+ knots range for at least 48 hours on average. In all cases, high pressure remained strong enough over the mainland to generate an elevated baseline of westerly winds – even when SLP north of Point Barrow wasn't especially low. That said, the SLP analog forecast does not capture the same mini-high pressure that the global models suggest will switch the winds to southeast after Day 4.

As previously noted, this year's ICEX camp occurs during a period of atmospheric conditions not typically experienced during prior ICEX missions. Once again there is very little correlation between today's conditions and previous breakup events.

With the Beaufort Sea fully cloud covered, there is no update on ice conditions from UAF today.

Day-by-day

Day 1, Mar 14: Continued southwesterly winds becoming more westerly; blowing snow; winds not quite as strong as Friday

Day 2, Mar 15: Light-to-moderate Southwesterly winds shifting to southeasterly

Day 3, Mar 16: Brisk SW winds, light snow (especially in a.m.) as weak low-pressure trough passes by; the combination of light snow and winds in the 10-20 knot range could result in some blowing snow, most likely limited to low levels

Day 4, Mar 17: Light winds early, increasing to moderate E/SE; Low pressure enters Chukchi

Day 5, Mar 18: East/Southeast winds as Low moves north of Chukchi Sea

Day 6, Mar 19: Light-to-moderate winds, generally from southern quadrant; Low well to north

Day 7, Mar 20: Generally light winds; another Low enters Chukchi

Day 8, Mar 21: Weak Low slides to the north with moderate SW winds over ICEX; light snow

Day 9, Mar 22: Generally light winds; Low moving east from Bering Strait with light snow

Day 10, Mar 23: Easterly winds; Low pressure to east, High pressure to northwest; light snow

Day 11, Mar 24: High pressure slides to east; Easterly winds increase

Day 12, Mar 25: Low tracks over ICEX area; SE winds shift to NW; light snow

• John Walsh, Brian Brettschneider, Lew Shapiro, Uma Bhatt, Tom Ballinger, Jackie Richter-Menge, Hajo Eicken.

12 Mar 2020 - Daily UAF science summary for ICEX operations

Posted 1800h ADT 12 Mar

As has been the case for the last week, models are locked in on a developing low pressure near Wrangel Island which is forecast to then move northeastward to north of Banks Island. Both the GFS and the ECMWF have nearly identical solutions (982 vs 983 mb). The GFS continues to anticipate strong winds from a winter storm with blizzard conditions on Friday and Saturday (March 13-14^th). Winds will be from the south-southwest direction initially, shifting to southwest, with falling and blowing snow. The winds will weaken and shift to coming from the south on the 15th of March.

A weak low pressure trough with light winds will pass through the ICEX area on Monday March 16th followed by a deeper trough mid-to-late week. There will be a period of moderately strong offshore winds in the middle of next week as the second storm system moves northwest of the ICEX region. For the period as a whole, southerly-to-southwesterly winds prevail; occasional light snow; notably warmer conditions than the preceding two weeks.

For the Analog forecast, we looked at similar instances of a closed low pressure near Wrangel Island, a large high pressure over the Mainland, and a big upper level high pressure over the southern Mainland. A handful of matches were identified. Notably, the March 26, 1996, and February 25, 2015, events were good matches for the initial conditions and the synoptic progression. Even though the March 1996 event had a better statistical match score, the February 2015 storm captured the track and pressure fields the following few days much better. The February 25-27, 2015, event is therefore the best analog in the previous 15 years. At Deadhorse, the winds were sustained from the southwest at 20-35 mph for 60 hours and the temperature was just below freezing for much of that time.

Most of the southeastern Beaufort Sea is covered by clouds today, but the area around the camp is visible. A number of new leads with a generally NE-SW orientation have formed during the day, one of which appears to be very close to the camp. The new leads suggest that the pack ice cover is expanding to the NW. However this will change as the storm that is currently affecting the area moves on and the winds turn and move the pack ice eastward. The leads created today will then close and the ice stress regime will become compressive. That could lead to significant ice deformation, particularly since the pack ice is currently in contact with the landfast ice in this area.

Examination of daily ice conditions spanning several days before and after the Analog storm dated February 25-27 2015 indicated active lead formation and open water near the Alaska North Slope fast ice after the storm passage. The current ice conditions appear more stable than in 2015 with fewer active leads.

• John Walsh, Brian Brettschneider, Lew Shapiro, Uma Bhatt, Tom Ballinger, Jackie Richter-Menge, Hajo Eicken.

11 Mar 2020 - Daily UAF science summary for ICEX operations

Posted 1800h ADT 11 Mar

The NOAA GFS forecast continues to anticipate winds of at least 20 mph beginning tomorrow night and lasting through Saturday night (March 14^th). Upon passing to the northeast of Wrangel Island, the intensity (~985 mb) and subsequent track from the northern Chukchi across the northern Beaufort through March 14^th are consistent with yesterday’s runs. Between this low and strong continental high pressure to the south over the Yukon and NWT, the pressure gradient will remain 60-70 mb for much of March 13^th and 14^thto support strong southwest to west flow. Snowfall of at least 1-2 inches is possible on the 13^th and combined with blustery conditions into the 14^th may dramatically limit visibility.

A series of cyclones is expected to follow this storm event, continuing with lows entering the west Arctic Ocean on March 15^th, 17^th, and 18^th. The March 18^th cyclone represents a notable change in the day’s forecast relative to last night’s model runs (from high pressure-dominant easterly flow in the Beaufort Sea from the 18^th to 20^th). Further, at 979 mb passing northwest of Wrangel Island late on the 18^th, this storm warrants close attention regarding its intensity and track over the coming days.

Passage of this series of storms is consistent with observations during the last 10-15 years, indicating that it is common during a pattern change from cold to warm, for a succession of storms (3-4) to take the same track. The first low is usually not the strongest.

Both the NOAA GFS and ECMWF model have the first storm predicted for the 12th/13th developing in the same location, at the same time, and within 1 mb of each other. Since analogs do not capture these features well using a forecast-scale domain, the reference area for the UAF analog forecasts has been expanded, to identify similar instances of a deep low pressure near Wrangel Island and strong high pressure over the eastern Interior and western Yukon. The top 20 matches for SLP at 48 hours (when the models show the low pressure fully closed off) and the top 20 matches for the 500 mb height field at 72 hours are shown in a table on the analogs webpage. Note that there are several common dates in the group.

A composite of the 5 best SLP matches and tracing following the winds over the next two days, we see that a core of strong southwesterly winds occurred all along the North Slope and offshore waters, with the peak values just to the west and south of the camp location. At the camp location, strong southwesterly winds around 12 m/s (23 knots) are typical on Day 1. By Day 2, a notable core of strong winds (10 m/s) is evident right along the entire North Slope coast, but not extending very far inland. My interpretation of these maps is that historically, these synoptic patterns generate strong southwesterly winds in the vicinity of the ICEX camp.

The only change in the configuration of the pack ice in the southeastern Beaufort Sea since yesterday, was a small shift to the north in the ice north of Point Barrow. The movement is indicated by the appearance of a new lead within the wider, existing lead along the coast north of Point Barrow.

Day-to-day summary of predicted conditions:

Day 1 (Mar 12): Light southerly flow, becoming southwesterly and strengthening to 20-25 mph late in the day with gusts approaching 40 mph

Day 2 (Mar 13): Southwesterly winds of 20-25 mph; possible gusts to 50+; cyclone entering the western Arctic Ocean; warming temperatures; snowfall of 1-2 inches possible

Day 3 (Mar 14): Westerly winds of 25-30 mph with the cyclone passing north of the camp and a strong high to the south; possible blowing snow with gusts to 45 mph

Day 4 (Mar 15): Winds from the west becoming southeasterly with a weaker cyclone entering the west Arctic Ocean

Day 5 (Mar 16): Southeasterly winds strengthening and becoming westerly as the cyclone passes just north of the camp; warming temperatures

Day 6 (Mar 17): Weak westerly winds becoming moderate and southeasterly as another low enters the west Arctic Ocean; temperatures warm through the day

Day 7 (Mar 18): Moderate southwesterly flow as the cyclone moves into the central Arctic; yet another low enters the western Arctic late in the day

Day 8 (Mar 19): Moderate southwesterly to westerly winds as the low passes over the camp heading east

Day 9 (Mar 20): Moderate westerly winds; the low tracks over the Canadian Archipelago

Day 10 (Mar 21): Moderate to strong westerly winds

• John Walsh, Brian Brettschneider, Lew Shapiro, Uma Bhatt, Tom Ballinger, Jackie Richter-Menge, Hajo Eicken.

10 Mar 2020 - Daily UAF science summary for ICEX operations

Posted 1730h ADT 10 Mar

Tomorrow’s weather is expected to be calm preceding stormy conditions beginning late Thursday (March 12). The most recent NOAA GFS forecasts show the predicted storm as slightly weaker than prior predictions. Comparing yesterday to today’s 15z forecast for March 13^th, the storm’s central pressure shows a 6 mb increase (to 984 mb) and slight westward drift (now west of Wrangel Island).

Regarding the storm event for March 12-14, the 10m winds over the camp are expected to intensify from 15-20 mph late on March 12^th, to 20-25 mph on March 13^th, to 25-30 mph on March 14^th and will be consistently southwesterly to westerly as the storm passes well north of the camp on the northern edge of Beaufort Sea. Light snowfall, combined with strong winds on the 13^th and 14^th, may limit visibility. Intensification of the winds reflects the strong pressure gradient anticipated between the storm system and high pressure extending from the Gulf of Alaska into the west-central interior of the state.

Southerly to westerly winds will continue to be at least moderate at the camp with relatively weaker cyclones entering the western Arctic on 15^th and 18^th. Toward the end of the ICEX campaign, more “normal” easterly winds are forecasted to return with high pressure expected to move into the Beaufort Sea from March 18-20 (Day 8-10).

Satellite imagery shows that large-scale ice conditions are virtually unchanged since yesterday, with some closing of leads at Point Barrow and the Mackenzie Delta.

The March 10 UAF analog predictions were adjusted somewhat to look at a bigger regional picture. As we have discussed for the last 5 or so days, a storm will be forming near Wrangel Island and will travel northeast from that position to a point about 500 kilometers north of Point Barrow. The latest runs of the GFS and ECMWF both show a 981-982 mb low developing west of Wrangel Island. Successive model runs have trended a little weaker with the low but a little stronger with the high pressure over the mainland. The sensible effect of this pattern is strong southerly winds and warmer temperatures. For the camp location, the analogs analysis does a good job at capturing local pressure changes. Unfortunately it does not capture the unusual strength of the low pressure to the north or the unusual strength of the high pressure to the south. A feature of outlier events is that the analogs struggle to find a sufficiently large number of matches. The strength and track of the unusual low pressure means a strong push of southerly (warm) winds is likely. The analogs do not capture this detail.

A feature this winter has been the very strong polar vortex. This feature has locked the observing pressure pattern in the region in place since mid-December. The developing storm may be the first step in the seasonal breakdown of the polar vortex.

As previously noted, this year's ICEX camp occurs during a period of atmospheric conditions not typically experienced during prior ICEX missions. Once again there is very little correlation between today's conditions and previous breakup events.

Day-to-day summary of predicted conditions:

Day 1 (Mar 11): Light winds from the south

Day 2 (Mar 12): Light southerly-to-southwesterly winds intensifying to 15-20 mph late in the day

Day 3 (Mar 13): Southwesterly winds of 20-25 mph; warming temperatures; snow with potentially limited visibility; cyclone moves into the northern Beaufort in the evening

Day 4 (Mar 14): Southwesterly to westerly winds of 25-30 mph; possible light and blowing snow; temperatures dropping late in the day

Day 5 (Mar 15): Moderate southerly to southwesterly winds; a cyclone enters the Chukchi Sea late in the day

Day 6 (Mar 16): Southwesterly flow increasing through the day as the cyclone moves eastward over the Beaufort

Day 7 (Mar 17): Moderate westerly winds with high pressure over the North Slope

Day 8 (Mar 18): Northerly winds veering easterly with high pressure in Beaufort; another cyclone enters the Chukchi late in the day

Day 9 (Mar 19): Moderate easterlies as the high moves north of the Archipelago; the cyclone weakens as it moves over the North Slope

Day 10 (Mar 20): Moderate easterly winds with high pressure over the western Archipelago

• John Walsh, Brian Brettschneider, Lew Shapiro, Uma Bhatt, Tom Ballinger, Jackie Richter-Menge, Hajo Eicken.

9 Mar 2020 - Daily UAF science summary for ICEX operations

Posted 1730h ADT 9 Mar

The regional wind and surface air temperature (SAT) response to the March 12-14 storm event has been qualitatively consistent in the 12z NOAA GFS model runs over the last 3-4 days. While the model continues to forecast a weakening of the storm’s central pressure upon entering the western Arctic Ocean, southerly winds and SAT are still expected to increase on the 12^th into the 13^th and may cause visibility issues at the camp with snow and blowing snow. Even with higher than previously predicted low pressure at the center of the cyclone (GFS: 976 hPa; ECMWF: 980 hPa), the storm qualifies as an extreme event, and has been recognized as such in a National Weather Service special weather statement released today. As the cyclone traverses toward the east on the 14^th, high pressure is anticipated to set up over north-central AK creating a strong pressure gradient and westerly winds. Comparatively weaker storms are forecasted to enter the west Arctic on March 15^th and subsequently on March 18^th. As these systems move east across the Beaufort Sea, the anomalous pattern of winds from the South and West, in the absence of a Beaufort High, is expected to persist.

Since yesterday, remote sensing data show little changes in the ice cover, with some of the new NNE-SSW leads noted yesterday extending further to the North, and the leads north of Point Barrow and across the Mackenzie Delta closing slightly.

The predicted storm will likely have a significant impact on the ice cover, which has not experienced major wind stress and associated deformation so far this winter. First-year and in particular young ice is expected to deform with rougher ice created as a result of the storm. Of particular concern is widening of concealed cracks after passage of the storm, which may affect ice runways and potentially variable-thickness sections of multiyear floes.

While the UAF analog model broadly captures large-scale conditions over the mainland and nearshore waters, as noted before analogs are ill suited to capture outlier events. Once again there is very little correlation between today's conditions and previous breakup events.

Day-to-day summary of predicted conditions:

Day 1 (Mar 10): Light northerly winds

Day 2 (Mar 11): Weak winds from the south, increasing late in the day

Day 3 (Mar 12): Strengthening southerly winds and rising temperatures through the day

Day 4 (Mar 13): Strong southwesterly winds; snow and blowing snow; above-average temperatures

Day 5 (Mar 14): Strong westerlies with blowing snow as the low moves northeast of camp and high pressure developing over north-central AK

Day 6 (Mar 15): Winds strengthening from the south as a second cyclone enters the western Arctic

Day 7 (Mar 16): Southerly winds becoming moderate westerlies as the cyclone moves into the northern Beaufort

Day 8 (Mar 17): Moderate westerlies weakening as the low migrates over the Canadian Archipelago

Day 9 (Mar 18): Southeasterly winds becoming southwesterly as another low enters the Chukchi Sea

Day 10 (Mar 19): Moderate southwesterly winds; warming temperatures

• John Walsh, Brian Brettschneider, Lew Shapiro, Uma Bhatt, Tom Ballinger, Jackie Richter-Menge, Hajo Eicken.

8 Mar 2020 - Daily UAF science summary for ICEX operations

Posted 1645h ADT 8 Mar

Ice conditions changed little since yesterday. A series of NNE-SSW trending leads opened in the southeastern Beaufort Sea, while a wide lead across the Mackenzie Delta and on to the Northeast closed somewhat. Most likely, the new leads were created as tension cracks and provided the expansion of the pack ice cover that was needed to close the larger lead. If current conditions hold (as predicted - see below), there is sufficient space for new NNE-SSW trending leads to be created, contributing to closure of the large coastal lead.

NOAA GFS predicts generally light winds for the period Monday through early Thursday, along with milder temperatures.

Forecasts remain on track for a major storm system to affect the Beaufort Sea later this coming week (Thursday-Saturday March 12-14). While there are uncertainties in the precise track and intensity, all models (GFS, ECMWF, Canadian, Navy NOGAPS) show a strong system in the Pacific sector of the Arctic Ocean by Friday March 13. If the current track and intensity verify, strong southwest winds and blowing snow will affect the ICEX area for two or three days.

After the main storm event of Thursday-Friday, winds of lesser intensity are forecast to be from the southwest and northwest quadrants as a second low pressure system passes over the area on Days 7-8). There is less confidence in this second storm system. By the end of the period (days 10-12), light to moderate winds from the southern quadrant are forecast. Day-to-day summaries are appended at the end of this update.

The overall pattern continues to represent a major departure from the climatological normal Beaufort High and its easterly winds over the ICEX region.

NOAA GFS and UAF analog forecasts are in strong agreement. Over the mainland, both the GFS and ECMWF now build a 1050+ mb high over the eastern Interior or western Yukon, with 1030+ mb pressure all the way to the west coast. The analogs, by their very nature, have a difficult time capturing outlier events; as such, they do not pick up on the possible Chukchi Sea low pressure by Day 5. The surface air temperatures in the analogs and the GFS are also in strong agreement. By Day 5, the GFS shows a 30F temperature rise due to the Chukchi Sea storm advecting warmer air northward.

As previously noted, this year's ICEX camp occurs during a period of atmospheric conditions not typically experienced during prior ICEX missions. Once again there is very little correlation between today's conditions and previous breakup events.

Drawing on NOAA’s CFSv2 seasonal prediction model, eight ensembles starting March 1, 2020 00z were processed and averaged to create weekly averaged wind magnitude and averaged zonal and meridional wind. Wind magnitudes for 8-14 March and 15-21 March are larger in the ICEX area than regions to the South and the North. Weekly averages reach between 5-7 m/s (10-14 Knots). Winds are zonal (W-E) the week of March 8-14 and more from the South the week of March 15-21.

Day-to-day summary of predicted conditions:

Day 1, March 9 Light winds, generally from the northwestern quadrant

Day 2, March 10 Continued light winds, variable direction

Day 3, March 11 Light winds, trending towards a more southerly direction

Day 4, March 12 Winds increasing from the south; start of significant warming

Day 5, March 13 Strong southwesterly winds; snow/blowing snow; warmer; strong L to NW

Day 6, March 14 Strong westerly winds; blowing snow; strong L to NE

Day 7, March 15 Brisk southerly to southeasterly winds; second L moves into Chukchi Sea

Day 8, March 16 West to northwest winds; L pressure to east, H pressure to west

Day 9, March 17 South winds develop behind H pressure to east

Day 10, March 18 Southerly to southeasterly winds continue, light to moderate speeds

Day 11, March 19 (spring equinox) Continuation of winds from southern quadrant

Day 12, March 20 Continued southerly winds; pattern is conducive to snow

• John Walsh, Brian Brettschneider, Lew Shapiro, Uma Bhatt, Tom Ballinger, Jackie Richter-Menge, Hajo Eicken.

7 Mar 2020 - Daily UAF science summary for ICEX operations

Posted 1630h AST 7 Mar

NOAA GFS predicts current offshore winds to slacken by tomorrow (Sunday) and remain light for the next few days. In agreement with previous model runs over the past several days, a major storm system continues to be forecast for late next week, with the strongest winds and blowing snow on Friday and Saturday March 13 and 14. Precise details of the storm’s track are still uncertain. However, in the most recent model runs, winds shift from offshore to westerly as the storm passes north of the ICEX area. The southwesterly winds remain brisk for another day or two. GFS hints at a continuation of the stormy pattern beyond March 14. There is still no sign of the climatological normal Beaufort High in the wind forcing through the next two weeks.

The March 7, 12UTC UAF analog forecasts have a much better handle on the sea level pressure features north of the Alaska coast today. They show the areas of low pressure diving from NW to SE across the Beaufort Sea, with agreement between models. At the upper levels, the individual analogs show a lot of variability, but the analogs’ mean closely resembles the GFS and the ECMWF with a deep upper low developing over the Chukchi Sea and a huge high pressure over the southern mainland and Gulf of Alaska by Days 4-5.

As previously noted, this year's ICEX camp occurs during a period of atmospheric conditions not typically experienced during prior ICEX missions. With a better handle on the pressure pattern, the previously identified weak correlations with some breakup dates in 2014 have almost completely gone away.

The satellite imagery collected today was generally cloudy. The noticeable changes were the appearance of a probable shear zone just off Barter Island and a family of arching leads, concave to the South, well north of the coast. If there was differential motion of segments of the ice pack, then the movements were too small to be detected at the scale of the imagery.

• John Walsh, Brian Brettschneider, Lew Shapiro, Uma Bhatt, Tom Ballinger, Jackie Richter-Menge, Hajo Eicken.

6 Mar 2020 - Daily UAF science summary for ICEX operations

Posted 1715h AST 6 Mar

The leads that appeared today cover a large area and reflect some movement of pack ice further north apparent in satellite images from earlier today. However, the density of the leads and their appearance in the area of the camp was not anticipated, given how stable the pack ice in that area has been. The lead across the Mackenzie Delta indicates that the area may become less stable when the wind shifts.

Consistent with the NOAA GFS forecast from yesterday, today’s forecast continues to show a moderate southerly wind event tonight (10-15 mph) that should give way to weak winds by early morning tomorrow (Mar 7th). Relatively light winds are expected over the camp until March 12th, but are expected to veer from south to north during that time.

A cyclone is forecasted to move across Chukotka into the Chukchi Sea on March 13th. The March 13th 15z forecast, relative to yesterday’s forecast for this same date and time, shows the storm just northeast of Wrangel Island now at a minimum sealevel pressure of 961 hPa, indicating a slight weakening (~2 hPa). The European ECMWF forecast also indicates a reduction in forecast strength of the storm, with ECMWF predicted minimum sealevel pressure now up to 971 hPa. The storm of record for this time of year is somewhere in the 960s hPa. The forecasted track of the system on the 14th and 15th is also trending slightly northeast of its anticipated position indicated by yesterday’s forecast. Winds nevertheless are expected to still be strong and from the southwest to west over the camp during this stormy couple of days.

The UAF analog forecasts have captured the dominant pressure pattern both north and south of the ICEX camp. Weak low pressures that cut off in the Beaufort Sea, as shown in the GFS, are hard for the analogs to resolve – as they are best at handling large-scale patterns. Throughout the next 5-days, the zonal (W-E) wind analysis shows increasing westerly winds over the next five days (good agreement with the GFS). Winds do not appear overly strong though.

As previously noted, this year's ICEX camp occurs during a period of atmospheric conditions not typically experienced during prior ICEX missions. The continued low correlations with significant breakup events in previous years should be viewed with caution. Today's SLP initialization has a modest (10%ile) match with March 24 & 25, 2014.

• John Walsh, Brian Brettschneider, Lew Shapiro, Uma Bhatt, Tom Ballinger, Jackie Richter-Menge, Hajo Eicken.

5 Mar 2020 - Daily UAF science summary for ICEX operations

Posted 1700h AST 5 Mar

SNPP-1 VIIRS satellite imagery shows that new leads formed over a wide area that includes the ICEX camp region in a matter of hours. However, in keeping with the unusual behavior of the ice cover in the absence of a Beaufort high, ice displacements seem to have been small, such that the ice pack is still tightly packed into the southeastern Beaufort Sea. The anticipated shift of winds to flow to the West may change that.

The NOAA GFS runs continue to indicate two weather events of note. In the near-term, a moderate, southerly (from the South) wind event is forecasted for tomorrow, March 6 with winds strengthening to ~10-15 mph by late afternoon and continuing until early Saturday morning. The UAF analog model output and the GFS both show a sharp sealevel pressure drop over the next two days. A new variable added to the analog model today is the eastward wind component. Over the 5-day period, the analog forecast shows a slightly stronger westerly (from the west) wind component by about 2 meters per second.

While seven days out, the GFS continues to show a storm moving through the Bering Strait and entering the Chukchi Sea on March 12th, with a low pressure of 957 mb. This will impact the wind field across the Beaufort Sea, leading to strong southeasterly winds that are forecasted to become westerly to southwesterly as the low tracks eastward on March 13-14. In the present forecast, the core of the low during this event is expected to remain north of the camp as it moves from west-to-east across the Beaufort Sea. The track and intensity of the storm warrant close attention in coming days.

The European ECMWF is now forecasting the same storm in the same location at the same time and has an even lower pressure of 952 mb. This is a major change from previous runs of the ECMWF. The forecast path and evolution of the storm looks nearly identical to the GFS. Note however, that all global models have struggled mightily this season with the forecast beyond Day 5 due to the strong polar vortex and positive Arctic Oscillation. The confidence in this solution, even with agreement between both models, is lower than we would typically expect. Furthermore, a storm with this low pressure value in the Chukchi Sea might be unprecedented.

A key concern with passage of such a storm is the presence of larger swaths of young sea ice that has not been subjected to such strong wind stress during the current ice season. Passage of the storm may hence result in substantial ridging and rafting which in turn would create room for fragmented floes to fully separate.

Consistent across the model runs for the next 10 days is the absence of persistent climatological easterlies over the Beaufort Sea. The ongoing wind direction anomaly can be attributed, in part, to the continued strongly positive phase of the Arctic Oscillation.

• John Walsh, Brian Brettschneider, Lew Shapiro, Uma Bhatt, Tom Ballinger, Jackie Richter-Menge, Hajo Eicken.

4 Mar 2020 - Daily UAF science summary for ICEX operations

Posted 1700h AST 4 Mar

NOAA GFS and the UAF analog forecast align in predicting a moderate-strength (10-20 mph) southerly (from the South) wind event Th-Fri March 5-6. The associated shift in wind direction may open up leads in the vicinity of camp. Both GFS and analog forecast indicate that the worst of the cold is ending.

Most of the leads that have appeared on the satellite imagery for the past couple of days have now either closed or frozen over. Two new leads have opened near Barter Island, but aside from that, the southeastern Beaufort Sea ice pack remains tightly packed.

None of the sealevel pressure forecasts for up to 5 days out using the analogs approach are as high as a 5% match for pre-2018 historical breakup dates. This year's synoptic pattern, with a lack of a distinct Beaufort High, continues to be vastly different from those of previous ICEX years and the match probabilities may not represent historical probabilities.

Confidence is increasing based on NOAA GFS forecasts for an active weather pattern with storm passages during Mar 12-16. While day-to-day details of the forecast will likely change, it is increasingly likely that Week 2 (starting Mar 11) will be windier and warmer than Week 1 in the ICEX region. At this point in time, the predominant wind directions are forecast to be from the West and South, with periods of moderate to strong winds that would favor blowing snow.

• John Walsh, Brian Brettschneider, Lew Shapiro, Uma Bhatt, Tom Ballinger, Jackie Richter-Menge, Hajo Eicken.

3 Mar 2020 - Daily UAF science summary for ICEX operations

Posted 1745h AST 3 Mar

The NOAA GFS forecast indicates continued absence of sustained winds from the east (with moderate easterly/northeasterly winds on March 10 a possible exception) - in line with UAF analog forecasts both of which are linked to the lack of a pronounced Beaufort High. GFS continues to indicate a moderately strong offshore wind event for Thurs-Fri March 5-6, and little or no new snow through the period. A potential storm system is predicted to move into the Chukchi and Beaufort Sea region March 13 by a majority of inputs (GFS, Fleet Weather, NOAA North American Model), though confidence in detailed forecast is low at present. Note also that at present the analog model predicts low temperatures with this storm, whereas the other three models indicate warming.

None of the sealevel pressure forecasts for the next five days out are as high as a 10% match for pre-2018 ice-floe breakup dates. This year's synoptic pattern continues to be vastly different from those of previous ICEX years.

NOAA AVHRR satellite images show formation of a lead pattern that extends from west to east across the region of interest, forming in a matter of hours in the absence of a strong weather system. This serves as a reminder that leads can be created by regional forces that are not apparent at the local observer scale.

• John Walsh, Brian Brettschneider, Lew Shapiro, Uma Bhatt, Tom Ballinger, Jackie Richter-Menge, Hajo Eicken.

2 Mar 2020 - Daily UAF science summary for ICEX operations

Posted 1715h AST 2 Mar

A NOAA 20 image from 13:22 AST shows new leads have opened in the past 6-7 hours, progressively from west to east. The most easterly has opened within the last 1.5 hours. The leads are forming despite the absence of strong local winds, indicating that the process is being driven by regional forcing which is causing the ice pack to expand to the West. At present, there is little space in that direction for large ice movements, but apparently that is not preventing the leads in the area from opening. Predicting how this process will continue, and how it might affect operations, is not possible now. It will be necessary to be aware that the process of opening the leads is continuing and to be alert for local changes.

The short-term NOAA GFS forecast remains consistent from previous days with relatively weak winds anticipated at the camp during the next two days. These calm conditions are forecasted to be followed by moderate southerly winds and above-normal surface air temperatures near the camp during the afternoon of March 5ththrough the 6th. The NOAA GFS model continues to forecast a strongly positive Arctic Oscillation index for the next 10 days, suggesting continued absence of a Beaufort High and accompanying easterly wind regime in coming days. Two events to keep an eye on in coming GFS runs include the short-term intensification of easterly winds on March 9th, followed by a March 11-12 south wind/warm event associated with a cyclone predicted to move northeastward through Bering Strait.

For the first time, the UAF analog forecasts are beginning to show (at Day 4 of the forecast) some 20% matches with ice breakup events from prior to 2018.

Analog forecasts overall are well aligned with NOAA GFS model predictions, showing a strong area of high pressure over the mainland with weak low pressure north of 75N. The analog forecasts have outperformed the GFS model in predicting low surface air temperatures.

• John Walsh, Brian Brettschneider, Lew Shapiro, Uma Bhatt, Tom Ballinger, Jackie Richter-Menge, Hajo Eicken.

1 Mar 2020 - Daily UAF science summary for ICEX operations

Posted 1700h AST 1 Mar

Leads along the shorefast ice have closed substantially since yesterday. The ice camp is located at the northern edge of a stretch of pack ice with numerous jagged, N-S-trending openings. These terminate where they intersect the older lead system that passes just north of the camp. The E-W lead north of the Mackenzie Delta has also closed since yesterday. These lead closures reflect the broader shift of the ice pack to the South, with smaller N-S trending leads forming to accommodate changes as the ice pack compresses against the coast.

Both NOAA GFS and the UAF analog forecast predict continued moderate winds from southerly and westerly directions, in the absence of a Beaufort High. Lower than normal pressure over the Beaufort Sea is part of the large-scale high Arctic Oscillation Index pattern with warmer than normal conditions across Eurasia and large parts of the Lower 48 states. This pattern is predicted to persist at least through next week, and will help keep the ice pack reasonably tightly packed into the Beaufort Sea.

The March 5-6 wind event stemming from a low-pressure system north of the camp is still forecasted by NOAA GFS to produce moderate southerly flow; however, the winds are now expected to be weaker for this event relative to yesterday’s forecast. Given this change in the forecasted wind speed, we should continue to keep close watch on the storm’s forecasted track and intensification in coming days. While a high-pressure pattern is expected to move west-to-east across the Beaufort Sea late next weekend into early the following week (March 8-9), persistence in the climatological Beaufort High and easterly winds continue to be absent in the GFS runs.

As with previous days, none of the UAF analog forecast days are even slight matches to patterns during floe break-up in past ICEX campaigns.

• John Walsh, Brian Brettschneider, Lew Shapiro, Uma Bhatt, Tom Ballinger, Jackie Richter-Menge, Hajo Eicken.

29 Feb 2020 - Daily UAF science summary for ICEX operations

Posted 1730h AST 29 Feb

NOAA’s 10-day GFS forecast predicts generally quiescent weather except for a West/Northwest wind event Thursday-Friday Mar 5-6 in association with a storm system passing to the North; light snow/blowing snow increasingly likely with this system if the forecast storm verifies. Below-normal temperatures are predicted for early in the week, moderating late in the week. With continued absence of the Beaufort high there is a continued lack of the climatologically typical easterly (East-to-West) wind forcing.

Most of the area is currently covered by clouds, but earlier NOAA NPP-VIIRS imagery from today showed new leads that had formed in the vicinity of the camp (and pre-existing leads in the area that were active), and further south off Barter Island. The displacement leading to such openings is the result of pack ice movement to the Northeast under the influence of winds associated with a low pressure moving into the area.

Movement over the past couple of days has created openings in the pack, in particular near the coast. With shifting and increasing winds forecast for the coming days, there is space for a rearrangement of the ice pack. Once that wind shifts direction towards flow from the Northwest, it may help to watch for cracks in the vicinity of camp and runway.

The analog forecast diverged slightly from the GFS prediction, and did not capture the high pressure pattern well. Analog output should be interpreted with caution for the next couple of days.

• John Walsh, Brian Brettschneider, Lew Shapiro, Uma Bhatt, Tom Ballinger, Jackie Richter-Menge, Hajo Eicken.

28 Feb 2020 - Daily UAF science summary for ICEX operations

Posted 1700h AST 28 Feb

Numerous leads formed in the area north and west of Point Barrow since yesterday under the influence of the advancing low pressure system. The lead from Point Barrow also seems to have widened indicating that pack ice has been displaced slightly to the North. There also appears to be some new lead activity between the camp location and Barter Island.

NOAA’s 10-day GFS forecast indicates a continued absence of major winds from the East for the coming week. The lack of the normally prevailing high pressure system to the North of the Beaufort Sea is in contrast with conditions during ICEX 2018. No major snowfall events are predicted, although several episodes of light snow are likely in the next week (beginning this weekend). Temperatures are forecast to be below-normal to normal temperatures for the next week. ecent model runs do not show good consistency in wind forecasts for Days 9-12, although they are consistent in indicating low pressure centers (storms) moving eastward into the vicinity of Bering Strait.

The analogs forecast continues to show strong high pressure over mainland Alaska. Unlike previous days, the historical analogs suggest the high pressure will drift into the Yukon Territory and then southeast. North of Alaska, the analogs have a weak signal for generally lower pressure. Analog forecast sealevel pressure pattern favors weak winds throughout the forecast period – west/southwest winds on Days 0-2 but variable afterward. None of the forecast variables show more than a 5th percentile match with critical breakup dates prior to 2018.

• John Walsh, Brian Brettschneider, Lew Shapiro, Uma Bhatt, Tom Ballinger, Jackie Richter-Menge, Hajo Eicken.

27 Feb 2020 - Daily UAF science summary for ICEX operations

Posted 1730h AST 27 Feb

The pack ice in the Southeastern Beaufort Sea has been stable, other than for slight shifting along some leads. This is indicated by the appearance of small openings that are visible in enlarged NPP VIIRS imagery. A possible small lead appeared just south of the camp late today (Feb 27) but could not be identified on earlier radar images.

Today’s NOAA GFS forecast is consistent with yesterday’s showing the persistent high-pressure cell over northern Yukon and Alaska coupled with a low-pressure system moving into the northern Beaufort Sea late Friday, supporting winds from the West to Southwest. A high-pressure cell is anticipated to move into the Beaufort Sea on Monday bringing winds initially from the Northeast that are forecasted to become more easterly late in the day and then turning to southerly (from the south) on late Tuesday into early Wednesday morning before turning to the south/southwest direction as the high migrates into the Northwest Territories. In the long-range, the predicted migration of a cyclone into the Bering Sea next Saturday and Sunday (March 7-8) deserves attention.

The analog forecast is broadly consistent with the GFS prediction, showing strong high pressure over mainland Alaska and low pressure due north of Alaska (see detailed discussion). None of the forecast variables show a significant (more than 10 percentile) match with critical ice breakup dates in earlier years.

• John Walsh, Brian Brettschneider, Lew Shapiro, Uma Bhatt, Tom Ballinger, Jackie Richter-Menge, Hajo Eicken.

26 Feb 2020 - Daily UAF science summary for ICEX operations

Posted 1730h AST 26 Feb

NOAA’s GFS predicts near-surface winds to remain weak and from the west through this Sunday in the absence of a Beaufort High. Winds are forecasted to turn northerly (i.e. from the north), but remain weak from Monday to early Wednesday with a high pressure cell moving across north-central Alaska. From Wednesday to Saturday next week the forecast suggests a return to flow from the West and Southwest. On Sunday March 8, the passage of a North Pacific cyclone through Bering Strait may yield winds from the South and an intrusion of warm, moist air into the southern Beaufort Sea.

The analog model shows the same basic pattern as the previous two days, agreeing broadly with the GFS forecast. However, while the trend for high pressure over the mainland remains strong, the signal for lower pressure north of 75°N is now stronger. This suggests stronger winds from the West and Southwest in the next several days. The axis of high pressure over the mainland looks to shift west and southwestward through the 5-day forecast period. Compared to the GFS, the analogs move the air masses along at a faster pace than the GFS. This is consistent with the pattern most of the winter. None of the next 5 days is close to a match with previous critical breakup events.

Note that Fleet Weather forecast and UAF’s WRF forecast indicate shift of winds on Feb 27 (Thursday) to come from the Southeast, in contrast with GFS and analog forecast.

The monthly wind outlook from NOAA’s CFSv2 forecast indicates steady but weak mean flow from the East over the ICEX area for the month of March.

Cloud cover obscured views of the surface, no new information on evolving lead patterns. However, the forecasted wind development will help stabilize ice conditions well into next week.

• John Walsh, Brian Brettschneider, Lew Shapiro, Uma Bhatt, Tom Ballinger, Jackie Richter-Menge, Hajo Eicken.

25 Feb 2020 - Daily UAF science summary for ICEX operations

Posted 1700h AST 25 Feb

Leads trending SSW-NNE were first identified in a NPP-VIIRS satellite image from early morning Feb 25, and appear to be close to camp. These leads were absent on the last images acquired on the previous day, and may be similar to leads seen further east (Floe U & P) during the Feb 23 recon flight. They present the possibility that new cracks and openings all the way up to full-blown leads may be generated between the main leads in the immediate vicinity of the camp.

At the same time, moderate winds from the West are predicted by both the GFS forecast system and the analog forecast for the coming days. Such mild westerly flow can help reduce further opening of the pack, and may help close existing leads in the coming days.

More specifically, the absence of the “Beaufort High” pressure system in the GFS forecast means an absence of prevailing east-to-west winds over the next 7-10 days. (The Beaufort High is a climatological high pressure feature in late-February – March, normally to the north of the ICEX area – as in 2018.)

A strong majority of analog forecast runs supports the development and strengthening of a strong high pressure in the northern half of mainland Alaska. This, combined with generally lower pressure to the North, will favor modest winds from the West. This sealevel pressure analog forecast is consistent with the GFS forecast. None of the next five days in the analog forecast are a pattern match with any of the atmospheric conditions that led to critical floe breakup in 2016 and earlier.

The GFS forecast indicates little new snow over the next 7-10 days, as only a few weak low pressure systems track from West to East north of the ICEX area. No strong storms or high-wind events in the forecast for at least the next week. Temperatures generally in the near-normal to below-normal range, with below normal most likely early in Week 2 (March 7-9).

• John Walsh, Brian Brettschneider, Lew Shapiro, Uma Bhatt, Tom Ballinger, Jackie Richter-Menge, Hajo Eicken.

Summary of March 2020 Winds north of Alaska

Posted 23 Feb 2020

Based on the GFS forecasts for the Beaufort region, there is a general absence of easterly winds during the next two weeks, especially compared with the 2018 ICEX period. No strong wind events in the forecast. There is also very little precipitation in the next two weeks. The previous two items together imply little change in snow conditions and little chance of significant blowing snow.

The ensemble of monthly CFSv2 winds has weak easterly to southeasterly winds over the ICEX area for March 2020. The wind direction is steady in the ICEX domain among the 24 ensembles. This is consistent with the GFS forecast for the next two weeks.

There is not a strong message from the short-range analog forecasts. The short-term analog years are not ones that are known for strong divergence and lead formation events. The monthly analog forecasts will become more skillful when we can incorporate the February data into the analog forecasts for March.

Repeating the key point: a general absence of sustained easterly winds that normally prevail this time of year.

• Uma Bhatt, Brian Brettschneider, John Walsh