10W (Lekima) Advisories

Center Track Forecast

A Center Track Forecast has not been issued for this advisory, as it is an intermediate advisory.

Advisory 4A

17Z/August 9

1-minute sustained wind: 95 knots; 110 mph; 175 km/hEstimated minimum pressure: 932 mbCurrent position: 28.3N 121.5W

Public Advisory

10W (Lekima) currently has winds of 120 knots, or 140 miles per hour, with an estimated minimum pressure of 920 millibars, and is moving north-northwest at a forward speed of 7 knots. Lekima will pose a rainfall threat for the Philippines, and is expected to directly affect Taiwan, China, and parts of the southern Japanese islands within the next 5 days.
10W (Lekima) has made landfall near Wenling, China, with winds of 95 knots, or 110 miles per hour, with a minimum pressure estimated at 932 millibars. Lekima is currently expected to turn north and rapidly weaken due to interaction with mountainous terrain. As such, this will be the final TCD advisory on 10W (Lekima).

Scientific Discussion

No scientific discussion has been written for this advisory.

Forecaster ID

MCK

...10W weakening...

Center Track Forecast

12 hours: 120 knots; 140 mph; 220 km/h24 hours: 115 knots; 130 mph; 215 km/h36 hours: 100 knots; 115 mph; 185 km/h48 hours: 80 knots; 90 mph; 150 km/h72 hours: 65 knots; 75 mph; 120 km/h96 hours: 45 knots; 50 mph; 85 km/h120 hours: 25 knots; 30 mph; 45 km/h

Track Forecast Confidence: Low (65%)

This is the probability that the storm will remain within the forecast cone throughout the forecast period. Our forecast cones are currently tuned so that storms being forecasted will be within the cone 3/4 of the time.

Advisory 4

1-minute sustained wind: 125 knots; 145 mph; 230 km/hEstimated minimum pressure: 905 mbCurrent position: 26.3N 123.5E

Added Best-Track Data

Closest pass to land: 12Z/August 8: 24.4N 124.9E; 1-minute sustained wind 135 knots (155 mph), MCSLP: 900 mb

Public Advisory

10W (Lekima) currently has winds of 125 knots, or 145 miles per hour, with an estimated minimum pressure of 905 millibars, and is moving northwest at a forward speed of 11 knots. Lekima is expected to continue northwest and is expected to post a significant threat to the Chinese coastline.

Scientific Discussion

10W's satellite presentation has quite clearly surpassed the peak, though it did not do so early enough, having lashed Miyakojima and Ishigaki near peak intensity. Thankfully, however, trochoidal wobbles prevented the extremely violent inner core from directly lashing any land. At this time, an eyewall replacement cycle seems to have concretely begun, with a very large second eyewall taking shape around a very small, 8 nautical-mile inner eyewall. As such, Lekima's appearance is degrading, and as predicted, so is the intensity. Dvorak estimates range from CI6.0/115 knots to CI6.5/127 knots; the ADT is at CI6.5/127 knots, and SATCON interestingly remains at 142 knots from 21z. Given the age of the most recent SATCON estimate I will provide more weight to the Dvorak estimates, setting the intensity at 125 knots for this advisory. The pressure will be kept low due to eyewall replacement cycle dynamics as well as evident expansion of the circulation.
The track forecast is now beginning to bounce slightly to the west. Trochoidal wobbles were initially sending Lekima in a much more northward track than before, though at this time there now appears to be a trend back towards the west, potentially putting China directly at risk of a landfall. Most models are quite tightly clumped together for the short-run, depicting a landfall in China within 18-24 hours. The storm will then move to the north in an interaction with a trough to the northwest. The intensity forecast is now more of a prediction of decay due to an eyewall replacement cycle and close land interaction. After the short-term (<72 hours), Lekima is expected to be weak enough and sufficiently decoupled that its interaction with the upper level trough will cease, and then move southward under influence of Krosa's encroaching circulation. Given this data, TCD forecasts a dissipation into a remnant low by forecast hour 96.

Forecaster ID

MCK

Advisory Archive

Below is an archive of previous advisories for 10W.

Center Track Forecast

12 hours: 125 knots; 145 mph; 230 km/h24 hours: 120 knots; 130 mph; 220 km/h36 hours: 105 knots; 120 mph; 195 km/h48 hours: 80 knots; 90 mph; 150 km/h72 hours: 65 knots; 75 mph; 120 km/h96 hours: 45 knots; 50 mph; 85 km/h120 hours: 25 knots; 30 mph; 45 km/h

Advisory 3A

05Z/August 8

1-minute sustained wind: 130 knots; 150 mph; 240 km/hEstimated minimum pressure: 907 mbCurrent position: 23.6N 125.7E

Public Advisory

The purpose of this intermediate advisory is to update the intensity of Lekima. More recent data suggests that Lekima is stronger than previously estimated, now with winds of 130 knots, or 150 miles per hour, with a minimum central pressure of 907 millibars. A change in the center track forecast is reflected on the left.

Scientific Discussion

CIMSS SATCON has updated in the past two hours with newer estimates, now suggesting that Lekima had peaked with winds of 137 knots. Dvorak estimates from TCD remain at T6.0/115 knots, and owing to a slightly constricting ring of cold convection (likely due to diurnal convective variation), SAB Dvorak estimates lowered to T5.5/102 knots, though the CI from SAB remains at CI6.0/115 knots. As a nod to the automated data, as well as the eye clearing out since the posting of Advisory 3, I am increasing the intensity estimate to 130 knots for the intermediate advisory.
The center track forecast will retain the same forecast positions, with an adjusted wind forecast to reflect the new data.

Forecaster ID

MCK

...10W a powerful typhoon...

Center Track Forecast

Track Forecast Confidence: Low (65%)

Advisory 3

1-minute sustained wind: 120 knots; 140 mph; 220 km/hEstimated minimum pressure: 919 mbCurrent position: 22.7N, 125.8E

Public Advisory

10W (Lekima) currently has winds of 120 knots, or 140 miles per hour, with an estimated minimum pressure of 919 millibars, and is moving northwest at a forward speed of 7 knots. Lekima will pose a direct threat to Taiwan, China, and parts of the southern Japanese islands within the next 5 days.

Scientific Discussion

10W's satellite presentation has mostly stabilized since the intermediate advisory at 17Z. There continues to be a full ring of cloud tops of around -74 to -79C surrounding a somewhat obscured eye. This depicts a poor outflow regime for a storm of this intensity, with most of the outflow aimed southward and to the west, where the storm's inflow is sourced from. Regardless, the storm is displaying quite voracious characteristics. The storm may have peaked for now, with an eyewall replacement cycle potentially imminent based on microwave data. Dvorak estimates from both the TCD and SAB are at T6/115 knots, ADT is at 119 knots, and the SATCON is depicting 125 knots at this time. I will take the average of these values and set the intensity at 120 knots for this advisory.
The track forecast continues the eastward trend depicted yesterday. At this time, Lekima is expected to continue northwestward under the influence of a ridge, which is expected to weaken under the presence of an encroaching trough to the west. From there, the steering currents are expected to become fairly volatile, with Lekima moving directly to the east of a PV anomaly. Some models expect Lekima to engage in a Fujiwhara-like interaction with the PV anomaly, creating a counter-clockwise loop before moving eastward with the westerlies. Some other models, however, do not depict a PV anomaly, and instead depict Lekima stalling due to the proximity of 11W (Krosa) to the east. For now, I am going to straddle the middle ground with the track forecast. In terms of the intensity forecast, Lekima may have leveled off for now, though synoptic conditions ahead suggest that Lekima will be able to vent out more properly, and possibly radially. At this time, however, microwave imagery as well as the outflow profile suggests that Lekima has likely peaked at this time, and will weaken due to a potential eyewall replacement cycle within the next 24 hours. Afterwards, due to land interaction with Taiwan, Lekima will begin to weaken despite SSTs of 29-30C and little vertical wind shear. By FH84, Lekima will cross the 28C isotherm, and SSTs will rapidly decrease while vertical wind shear will rapidly increase.

Forecaster ID

MCK

Center Track Forecast

A Center Track Forecast has not been issued for this advisory, as it is an intermediate advisory.

Advisory 2A

17Z/August 7

1-minute sustained wind: 120 knots; 140 mph; 220 km/hEstimated minimum pressure: 920 mbCurrent position: 21.9N 126.4E

Public Advisory

Scientific Discussion

Lekima's explosive intensification in the past 17 hours is quite remarkable. Currently infrared imagery is depicting a full ring of cloud tops of at least -78C, with peak cloud tops at around -85C. There is a significant inflow coming from the Luzon Strait, with a slight second inflow. However, there is only a moderate outflow (mostly aimed southward), which may serve to limit the storm's intensity.
SAB and TCD analysts came in with Dvorak estimates of T6/115 knots. However, the CIMSS ADT is suggesting winds of 122 knots, and the SATCON is estimating 120 knots. For this intermediate advisory I am setting the intensity at 120 knots mainly as a nod to the ADT. Note that the pressure estimate is 920 millibars from the CKZ input; this is primarily due to the storm's large size as well as the very low environmental pressure.

Forecaster ID

MCK

...10W attains typhoon strength...

Center Track Forecast

12 hours: 90 knots; 105 mph; 165 km/h24 hours: 110 knots; 125 mph; 205 km/h36 hours: 125 knots; 145 mph; 230 km/h48 hours: 120 knots; 140 mph; 220 km/h72 hours: 85 knots; 100 mph; 155 km/h96 hours: 50 knots; 60 mph; 95 km/h120 hours: 35 knots; 40 mph 65 km/h

Track Forecast Confidence: Low (65%)

Advisory 2

1-minute sustained wind: 75 knots; 85 mph; 140 km/hEstimated minimum pressure: 955 mbCurrent position: 20.6N 128.0E

Public Advisory

10W (Lekima) currently has winds of 75 knots, or 85 miles per hour, with an estimated minimum pressure of 955 millibars, and is moving north-northwest at a forward speed of 6 knots. Lekima will pose a rainfall threat for the Philippines, and is expected to directly affect Taiwan, China, and parts of the southern Japanese islands within the next 5 days.

Scientific Discussion

There has been quite a bit of development in the past 24 hours. Recent microwave imagery reveals an eye feature beginning to close off, and the more recent satellite data, infrared and visible, is now showing an eye feature beginning to clear out. Dvorak enhancement shows a B (-70 to -75C) eye surrounded by a W ring (-76 to -81C), as elaborated by TCD Dvorak analysts. SAB Dvorak numbers from 21z are at CI4.0/65 knots, and TCD Dvorak numbers are at CI4.5/77 knots. The ADT is currently estimating CI4.4/75 knots. The SATCON estimate of 68 knots is discarded as it was from 18z. Giving more weight to the more recent estimates, the 1-minute sustained wind is set at 75 knots for this advisory.
The track forecast does not contain a significant change compared to yesterday, however the northward recurvature has been moved sooner in the track forecast, now taking Lekima just north of Taiwan (still close enough to cause direct impacts) and into a flirt with the Chinese coastline. It is still mostly established that a ridge to the north of 10W will provide the primary steering flow for the first 48 hours before a trough to the northwest begins to steer the storm northward. The intensity forecast as a result no longer displays much weakening due to lesser land interaction, but given statistical data, there is reason to break general TCD forecasting constraints: Lekima is expected to attain Category 4-equivalent winds within 36 hours, currently expected to peak with 125 knots, though given a dual inflow this may even be conservative.

Forecaster ID

MCK

...10W gradually strengthens...

Center Track Forecast

12 hours: 65 knots; 75 mph; 120 km/h24 hours: 80 knots; 90 mph; 150 km/h36 hours: 95 knots; 110 mph; 175 km/h48 hours: 105 knots; 120 mph; 195 km/h72 hours: 65 knots; 75 mph; 120 km/h96 hours: 45 knots; 50 mph; 85 km/h120 hours: 30 knots; 35 mph 55 km/h

Track Forecast Confidence: Average (75%)

Advisory 1

1-minute sustained wind: 55 knots; 65 mph; 100 km/hEstimated minimum pressure: 977 mbCurrent position: 18.7N 129.0E

Public Advisory

10W (Lekima) currently has winds of 55 knots, or 65 miles per hour, with an estimated minimum pressure of 977 millibars, and is moving northwest at a forward speed of 2 knots. Lekima will pose a rainfall threat for the Philippines, and is expected to directly affect Taiwan and parts of the southern Japanese islands within the next 5 days.

Scientific Discussion

10W continues to organize, with its CDO now expanding over the low-level circulation. Convection is now particularly strong, with peak cloud tops of around -86C. An ASCAT pass from 12z revealed peak wind speeds in the western quadrant at around 40 knots, coinciding with a T3/45 knot Dvorak estimate from the SAB at around that time. The most recent TCD Dvorak estimate, submitted at 00z, is at T3.5/55 knots, while the SAB estimate from 21z is at T3/45 knots. The raw T-numbers from ADT have risen since these previous observations, and now holds a CI of T3.3/51 knots. Thus, for this advisory, I am setting the intensity estimate at 55 knots.
The track forecast, compared to if an advisory was issued yesterday, is fairly straightforward. At this time, there are a few competing steering flows interacting with 10W's circulation: 09W (Francisco) to the north, potentially keeping 10W moving slowly westward, and a developing subtropical ridge south of Japan. This ridge will continue to strengthen and will become the main steering current for 10W. The intensity forecast, however, has some complications, particularly owing to 10W's recent development. Currently, models are depicting bulk shear of up to 30 knots, with SSTs of 30C and an 80% mid-level RH. While the shear is otherwise unfavorable for development, it is possible that 10W may rapidly intensify despite the presence of shear. Much of the bulk shear is expected to weaken to around 10 knots within 48 hours, thus paving the way for particularly strong intensification until 10W reaches the 28C isotherm. However, most models do not intensify 10W heavily, with most only intensifying it to 65 knots. For now, I will give heavy weight towards the higher outliers- the GFS and the HWRF, given the recent development.

Forecaster ID

MCK