Lesson 23: weather: the extreme edition!

Welcome back! Let’s get into our very last lesson on weather, and close this chapter. 

Today, we’ll learn about two types of special weather alerts that warn pilots about really bad weather. Pilots call them SIGMET and AIRMET Advisories. Please stand by.

SIGMETs are issued for extremely bad weather, while AIRMETs are for less severe (but still important) weather conditions.

Awesome! Let’s cover SIGMET Advisories first. 

SIGMET Advisories

SIGMET means Significant Meteorological Information. Like the name implies, these advisories warn us about the most significant – or extreme – kinds of weather events. It’s like a red alert for things like serious turbulence and thunderstorms.

Next up is AIRMET, which is like SIGMET’s little brother. 

AIRMET Advisories

AIRMET stands for Airmen's Meteorological Information. Like the name implies, these advisories warn us about less severe weather conditions like moderate turbulence, strong winds of 30 Knots (23 MPH) or more, and poor visibility.

Why should pilots care about AIRMETs, or less severe weather information? 

Great question! AIRMET is also super important. It alerts us to conditions like: 

• Moderate turbulence

• Strong winds of 30 Knots (23 MPH) or more

• Poor visibility

That information seems helpful for a drone pilot! So to recap, here are the differences between a SIGMET and AIRMET Report: 

Differences between SIGMET and AIRMET Reports

So, SIGMETs let us know about extreme weather events, and AIRMETs let us know about serious (but not extreme) weather events. These weather advisories were created with airplane pilots in mind, but drone pilots can benefit from them, too!

Today’s 🔑 Word!

SIGMET Advisory

SIGMET alerts warn pilots about really bad weather that could be dangerous.

Extreme Examples: 

• Severe thunderstorms 

• Very strong winds 

• Heavy icing on the plane

• Volcanic ash clouds

Before a flight, pilots can receive a weather briefing with this info. SIGMET alerts help pilots avoid dangerous weather, making sure everyone on the plane stays safe.

Today’s 🔑 Word!

AIRMET Advisory

Less Extreme Examples:

• Moderate turbulence (bumpy air)

• Moderate icing on the plane

• Low visibility because of fog or clouds

Awesome! That does sound good to use. Where can I find these reports? 

Here, you can check them out yourself online! You can find them on two sites:

• aviationweather.gov 

• on sectional charts!  

Let’s click here for SIGMET Alerts. 

Let’s click here for AIRMET Alerts. 

What do you notice? I really love the colors. 

Remember our good, old friend SkyVector? Did you know that you can actually look up SIGMETs and AIRMETs here, too?! 

Just click on “Layers” in the top right corner and then, select which advisories you want to see! Easy as that. 

You can totally use these tools to help you plan your flights! 

And… they’re way less intense to look at than METAR and TAF Reports! Haha. 

Phew! You’ve done a great job so far! 

Let’s take a much-deserved break.

Bio Break!

Welcome Back, future pilot!

Welcome Back! Now, we’re going to dive into more extreme weather, starting with extreme cold. 

Extreme Weather: Cold

You already know that really icy weather can impact your drone’s performance – it can literally make it fall from the sky! Ice messes with aerodynamics and can make flying very difficult. Ice can build up quickly, especially if you fly higher where it’s colder. Be aware of ice on your drone whenever it’s close to freezing and there’s moisture in the air.

Now picture this: you’re flying in the cold, and suddenly your fingers start to go numb. You can’t feel the controls of your remote at all!

That can be a real problem! 

And it’s not just your fingers. Remember LiPo batteries? They’re special, and super fragile batteries that our drones use.

LiPO batteries hate the cold too. In low temperatures, they don’t last as long and might not give you the same power. Always keep an eye on your battery level, no matter what the weather is like.

Now that we’ve covered cold weather, let’s talk about something really freaky – tornadoes! 

Extreme Weather: Tornadoes

Did you know that any cloud connected to a severe thunderstorm can cause tornadoes? Even if it’s miles away from the main storm cloud! 

Rule number one: definitely don’t fly near tornadoes. Keep your drone and yourself safe!

Extreme Weather: Hail

Did you know that thunderstorms and hail can go hand-in-hand?

Hail can come from those big cumulonimbus clouds that we know about now! What's interesting—and kind of scary—is that hail can fall from clear air a few miles away from the storm. So just because a thunderstorm seems far away doesn’t mean it’s safe to fly.

Watch out for icing and reduced battery performance in cold weather. Be cautious of hail, tornadoes, & lightning during drone flights. Remember, safety always comes first when flying drones, especially in extreme weather conditions.

Awesome! Is there anything else we need to know about extreme weather? 

Yes, there certainly is! Drone Pros need to be on the lookout for 5 Types of Extreme Weather. But first, can you guess what kinds of weather pilots should avoid?  

5 Types of Extreme Weather Drone Pros Should Avoid

1. Flying in the Cold

   • Cold weather might make your fingers numb, making it tough to feel the controls on your remote!

   • Drone batteries don’t work as well in cold weather! They may not last as long or give the same power, and your drone might lose battery. 

   • Pro Tip: Always keep an eye on your battery level, regardless of the weather conditions.

2. Tornadoes

   • Did you know that any cloud connected to a severe thunderstorm can cause tornadoes? Even if it’s miles away from the main thunderstorm cloud! 

   • Definitely don’t fly near tornadoes, or even be around them! 

3. Icing

   • Be careful about icing when it’s close to freezing and there’s water in the air.

   • Even during a flight, ice can form quickly, especially if you go up a bit higher where it's colder. 

   • If your aircraft gets frost or ice on it, it's going to have a hard time flying well, and might just fall back down. 

4. Hail

   • Thunderstorms can produce hail, especially under cumulonimbus clouds. What's interesting is that hail can fall from clear air, even outside the thunderstorm, a few miles away.

   • Just because a thunderstorm seems far away doesn't mean it's safe to fly. Even small pieces of hail can harm your drone, so be very careful 

   • if there are thunderstorms around, even if they're not right over you! 

5. Lightning

   • Lightning is really, really dangerous for drones. 

   • A lightning strike can break your Flight Controller and other electronics! It can also mess up the magnetic compass permanently. 

   • Even if lightning is far away, it can still mess up your radio signals (we’ll cover radio in the next lesson) making it hard to control your drone.

Drone Pro Safety Tips – Extreme Weather Edition

• Avoid flying near thunderstorms, even if they seem distant. 

• Watch out for icing and reduced battery performance in cold weather. 

• Be cautious of hail, tornadoes, and lightning during drone flights. 

• Safety always comes first when flying drones, especially in extreme weather conditions.

Things to Remember

• SIGMET: Significant Meteorological Information alerts about severe weather like thunderstorms or strong turbulence.

• AIRMET: Airmen’s Meteorological Information advisories for less severe weather, like moderate turbulence or low visibility.

• Thunderstorms are produced by cumulonimbus clouds, which are dense, fluffy, and tall.

• Conditions of a thunderstorm include high humidity, unstable air, and lifting force (warm air rising). 

• Phases of a thunderstorm are cumulus (rising air), mature (heavy rain/hail, strong winds), and dissipating (weakening storm). 

• Squall line thunderstorms have the most severe conditions like tornadoes and large hail.

• Embedded thunderstorms are hidden within other clouds and can be very dangerous.

• Flying in the Cold: Numb fingers affect control, batteries may perform poorly.

• Tornadoes: Can form near severe thunderstorms, so avoid flying near tornadoes.

Optional Review

Excellent Job! We’re Ready to Fly.

Great work! I see you’re all a few steps closer to becoming a certified drone pilot. 

Let’s Descent! Great work everyone.

For Educators: Optional wrap-up activities, games, quizzes, and temperature checks can go here, time-permitting.

See You Next Time! 

Over and Out.