The FAA's Pilot's Handbook of Aeronautical Knowledge covers weather theory in detail (Chapter 12).  You should become familiar with this chapter (embedded below).  Some of it is more relevant to crewed flight than Part 107 remote flight.  There are several key bits of information that you'll want to understand as a remote pilot.  The biggest concerns you face as a remote pilot have to do with wind and convective currents, because they affect the performance and controlability of your aircraft.  

There is also a Weather Handbook  that contains additional details.  As of Feb 2025, the current handbook is H-8083-28 from 2022.

Unless noted otherwise, images on this webpage are from the Pilot's Handbook of Aeronautical Knowledge.

Finally, pilot Jon Kotwicki has some great weather training on his Fly-8-Mike-Alpha website.  Visit https://fly8ma.com/lessons/lesson-14-aviation-weather/

Basically, uneven heating of the earth's surface by the sun and the resulting heat exchange  is the source of all weather.  Hot air rises, cool air sinks.  Barren, unvegetated, paved areas absorb and release heat faster than vegetated areas and water.  This creates convective currents that can affect your ability to control your aircraft.

The other global factor affecting air currents and weather is the rotation of the earth which creates the Coriolis force, and the orbit of the earth around the sun which creates the seasons.

Stability is with reference to vertical movement of air.  The atmosphere is considered unstable when air can move upward for long distances (think thunderstorm development and towering cumulus clouds).  Warming from below, such as the sun shining on pavement or rock, would cause this.  Stable air masses are typified by a warm air layer on top of a cooler air layer at the surface.  Questions about the characteristics below typically appear on the Part 107 exam.  As a remote pilot, you should recognize that unstable air - typically associated with the visibility you want - will be turbulent and rain showers may occur.  Stable air - associated with the kind of quiet air you'd like - will often have poor visibilty and steady rain.  It seems hard to win :-)

If you fly near the coast - or any large body of water - there are typical diurnal patterns for wind you should be aware of.  Note the uplifting and downdraft associated with each cycle.

Visit Fly-8-Mike-Alpha's fog training page for a great presentation of the 6 types of fog.

The ceiling is the height above the ground (AGL) of the lowest cloud layer that is Broken or Overcast.  This is particularly important for crewed aircraft flying under visual flight rules because of weather minimums.  For remote aircraft, remember that you must be at lest 500ft below the base of a cloud (and 2,000ft or horizontal separation from any cloud).

In aviation weather reports – and particularly METARs & TAFs (below) – sky condition is reported in terms of 1/8s of sky coverage by clouds as follows.

• Clear skies (SKC) ... 0/8 cloud coverage

• Trace (FEW) ... 1/8 - 2/8 cloud coverage

• Scattered (SCT) ... 3/8 - 4/8 cloud coverage

• Broken (BKN) ... 5/8 - 7/8 cloud coverage

• Overcast (OVC) ... 8/8 cloud coverage

Altitude is the height above the ground (AGL) or above mean sea level (MSL).  Altimeters are devices that measure altitude and report them in MSL.  

True altitude is the distance of the aircraft above MSL.  Absolute altitude is the distance AGL.  

You typically set the barometric pressure of your altimeter before you leave the airport and adjust it along the way.  This allows the altimeter to display an indicated altitutde that is close to the true altititude.  There is also something called pressure altititude which is what your altimeter would read if you set it to standard pressure (29.92" Hg).

There is a standard pressure (29.92" Hg) and temperature (15C) at sea level and a standard rate at which pressure and temperature change with altitude - that is the only time your altimiter's indicated altitude is the same as the true altitude.

Remote pilots don't need to get too caught up in this because of the altitude (AGL) limitations.  BUT one thing you should know about is density altitude [ video - he uses the chart wrong - he should go up to 112' ].  That's pressure altitude corrected for non-standard temperatures.  Basically, warm, moist air at high altitudes is less dense than cool, dry air at low altitude.  So if it's very hot and humid out, your aircraft will perform as if it were at a higher altitude.   And if it's cold and dry, it will perform as if it were at a lower altitude.

Example:  You're on an airstrip at 1,200ft MSL.  It's 90F.  The barametric pressure is 29.7" mercury. 

First, look at the table on the right side.  Look for the altimeter setting of 29.7" then look over for the pressure altitude correction factor, which is 205ft.  [ If your altimeter reads between the numbers on the chart, you'll need to do a linear interpolation. ]

Next, add that to the elevation of your airstrip to get 1,200 + 205 = 1,405.  So just because of the lower than standard pressure, the airfield is as if it were at 1,405ft.

But it's also kinda hot.  So now go to the bottom of the graph on the left and find 90F.  Follow the blue line up until you hit the 1,405 pressure altitude (black diagonal lines).  Well, there is no 1,405 line so you'll need to estimate where it would be between the 1,000ft and 2,000ft lines.  It's not going to be exact.  Then follow the blue lines straight to the left until you hit the Y-axis and that's your density altitude - about 3,600ft.  

So your aricraft is going to perform as if it were at an altitude of 3,600ft MSL.  The rotors will have to spin faster to genreate enough lift to leave the ground and stay in the air, so your battery life will be reduced.  You might also have trouble getting your aircraft off the ground if you have it loaded heavily enough.

The FAA's Pilot's Handbook of Aeronautical Knowledge covers aviation weather services in detail (Chapter 13).  You should become familiar with this chapter (embedded below).  Some of it is more relevant to crewed flight than Part 107 remote flight.  There are several key bits of information that you'll want to understand as a remote pilot.  As a remote pilot, you are typically concerned with the weather in a relatively small area, whereas pilots of crewed aircraft want to know how the weather will change as they fly large distances.

Unless noted otherwise, images are from the Pilot's Handbook of Aeronautical Knowledge.

A good place to get weather information is 1800wxbrief.com.  You can create a free account and look at weather briefs focused on an airport near where you will fly - this is called an area brief.  These briefings will include Airman's Meterological Information (AIRMET) and Significant Meterological Information (SIGMETS) (think icing, dust storms, thunderstorms, and such). 

Some terminolgy they might ask you about on the exam is the type of weather briefing you are looking at.

• Outlook briefing - flight is 6 or more hours from now

• Standard briefling - a complete briefing for a flight within the next 6 hours

• Abbreviated briefing - you're only asking about a few items, because you've gathered information elsewhere (this is mainly if you actually call and talk to a person and ask for an abbreviated briefing)

Note that your sessions on 1800wxbrief are documented on the system, which provides some evidence of due diligence in the event of a mishap.

The National Weather Services' Aviation Weather Center is very comprehensive and also freely available.  AIRMETS and SIGMETS are also available here.

UAV Forecast is designed for remote pilots and has a web interface as well as apps for Android and iPhone.  Apps like this can give you weather where you're standing or for anyplace you search.

If you have a radio capable of tuning civil aviation frequencies [ 118.0 - 136.975 MHz ] and you are near an airport, you can listen to some of the automated weather reports - AWOS / ASOS / ATIS - that include wind speed and direction, barometric pressure, and density altitude.  Many airports also have a phone number you can call to listen to those reports.  For example, for Triangle Executive (KTTA), dial 919.708.5382.  These numbers can be found on AirNav.com or in the Chart Supplements for each airport.

The FAA has a shorthand for weather reports at airports available to pilots.  You're expected to be able to read these reports for the Part 107 exam.

Meterological Aerodrome Reports (METARs) relate current conditions and Terminal Area Forecasts (TAFs) relate predictions for the next 24 hours.  There are numerous applications, such as Avia Weather, that decode the shorthand.  The Aviation Weather Center TAF (Products / TAF Data) or METAR (Products / METAR Data) pages will also decode for you.  But you're expected to know the code for the exam.  One fun way to learn the code is to get one of those applications, decode at the coded version, and then check your decoding against the official decoding.   The FAA  (source) and Weather Service (source) keys to decoding are below.