Weather Outside Your Window: AccuWeather School: The case of the breathing forest

By Kristina Pydynowski, AccuWeather senior meteorologist

Updated May. 17, 2021 8:28 AM EDT

AccuWeather School is back in session with more engaging and educational virtual lessons to help kids and interested adults learn more about the weather – and have fun doing so!

📓 May 14 - Homework: The case of the breathing forest

A forest breathing? Trees breathe in carbon dioxide and breathe out oxygen, but not like how you take a deep breath. They use photosynthesis instead.

However, let’s watch the video below – that looks like the forest is breathing!

What you are seeing are trees swaying in the wind and their roots moving back and forth. When the ground is really soggy, roots have a hard time holding onto the soil. Think of it this way – which is easier for you to grab, mud or dirt? Mud will slip through your fingers, not dry dirt.

Seeing a video of the forest breathing is neat, but when the roots don’t have a firm grip on the wet soil as winds are blowing, trees can easily get knocked down.

🎭 May 14 - Story Time: You’re not alone if you are scared of the weather

If you get scared when you hear thunder, see a dark cloud or any other type of weather, you aren’t the only one. One out of every 10 Americans may suffer from some degree of severe weather fear.

When you are scared of something, it is called a phobia. The most common phobia that you may know is claustrophobia, when someone is scared of being in tight places.

While people have phobias of thunder, lightning, rain, snow, and even the sun, it is usually not just the weather they are scared of. People worry about what will happen from that weather. Such as snow – most of us love seeing snow in the forecast, but someone who has a snow phobia is usually scared about getting stuck in their homes during a snowstorm.

🎶 May 11 - Music class: 5-second rule for thunderstorms

We aren’t talking about when you drop food on the ground – the five-second rule for thunderstorms will tell you how far away a bolt of lightning is:

Regardless of how far away the lightning is, remember that as soon as you hear thunder, you are close enough to be struck by lightning. Lightning often strikes more than three miles from the center of a thunderstorm, according to our friends at the National Weather Service, often when it’s not even raining!

Lightning is seen in the sky over the University of Kansas in Lawrence, Kansas, on Thursday, March 26, 2020. (AP Photo/Orlin Wagner)

📓 May 11 – Homework: Create a mini lightning bolt at home

Your homework is to create a mini lightning bolt at home – one lightning strike you don’t have to run and seek shelter from.

All you need is a balloon, compact fluorescent lightbulb (CFL) and someone willing to let you rub the balloon on their head.

As AccuWeather Senior Meteorologist Jason Nicholls demonstrates below, rub the balloon on your or someone’s head to build up a static charge. Then, hold the balloon to the metal tip at the end of the lightbulb. Don’t blink as you should see the lightbulb briefly flash like a mini lightning bolt. This experiment works best when the air is drier so you can build up that static electricity.

📚 May 7 - Study Hall: What does hail have in common with a tree trunk?

Hail and a tree trunk? One is a ball of ice that falls from a thunderstorm; the other is found in your yard or a nearby park – so what could these two things have in common? Let’s find out below:

A tree trunk gets a ring every year it is alive; a hailstone gets a ring every time it takes a ferris wheel ride in a thunderstorm. The more times a hailstone goes up and down in a thunderstorm, the larger it will get.

Hailstones can be as small as peas or as large as baseballs, softballs and even grapefruit. The largest hailstone to ever hit the United States was around the size of a volleyball! Not only would that have had many rings, but it would have been extremely dangerous.

📚 May 7 – Pop quiz! In which American state did volleyball-sized hail slam down in 2010?

If you guessed South Dakota, you are correct!

A hailstone with a diameter of a whopping 8 inches hit Vivian, South Dakota, on July 23, 2010. That’s about the size of a volleyball and is the largest hailstone on record in the United States. This hailstone also weighed about 1.94 pounds!

Look at the image of the record hailstone below – it looks more like a volleyball with spikes. As a hailstone tumbles around in the air, it takes on different shapes from being smooth to jagged. The bigger the hailstone is, the more likely it will look like a ball with spikes instead of something that will roll nicely on the ground.

An image of the record-setting hailstone that fell in Vivian, South Dakota, on July 23, 2010. (Photo/NWS Aberdeen)

🎨 May 4 - Art Class: Weather Photographer of the Year contest is underway

Do you like taking pictures of the weather? If so, you should consider entering your best photo in the Royal Meteorological Society’s Weather Photographer of the Year 2021 contest, in association with AccuWeather. One of the best parts of this contest is that it is free to enter – and you can win awesome prizes!

There are three categories you can enter – the main contest, which will crown the Weather Photographer of the Year 2021, along with Young Weather Photographer of the Year 2021 for our students aged 13-17 and a new category for photos taken just with mobile phones or tablets.

Why is there a Weather Photographer of the Year 2021 (Mobile Phone) this year? Because our phones can capture amazing pictures. Check out the photos below that show a perfect snowflake -- they were taken with nothing more than an iPhone!

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(Photo/Kristina Pydynowski)

AccuWeather is associated with this photo contest because knowing what weather is headed to your community through our free app may help you capture that amazing shot!

Be sure to only head out to take weather photos when it is safe to do so – head indoors as soon as you hear thunder, "Turn Around, Don’t Drown" when you see floodwaters and always seek shelter when a tornado warning is issued.

You have until June 29 to enter the contest with the winners announced in mid-October. You can also view the winners from last year to get ideas for your entry.

Good luck!

📓 April 30 - Homework: Put on your meteorologist hat ... find a storm on your own

You don’t need a smartphone or computer to know where a storm is on a weather map. Just step outside and stand with your back to the wind. Stick your left hand out, and you are pointing in the general direction of where the storm is – great work thanks to your human superpowers!

Why is it so simple? Earlier in AccuWeather School (when we exploded an egg in a bottle), we learned that winds always want to blow from high pressure systems (and nice weather) to storms (known as low pressure systems) in a counterclockwise fashion – so a storm will generally be to your left when wind is hitting your back (our friends in the Southern Hemisphere have to look to their right to see where a storm is since air flows in the opposite direction).

This trick may not work well if there is only a light breeze. When high pressure is providing nice weather and storms are far away, light winds can blow in different directions.

⛹️‍♂️ April 30 - Gym class: Crush a can with ocean-like strength

For most of you reading this, there is 14.7 pounds per square inch of pressure from the air pushing on you. Don’t feel it? That’s because your body is pushing back with the same force. However, if you took a very deep dive into the ocean (not recommended), the water pressure would be strong enough to break your bones.

Since we don’t want to see anyone break their bones, here’s one experiment demonstrating how air pressure can crush a can. You must have an adult help you with this experiment, but it is easy to do with an empty soda can, water, ice, tongs, potholder, and a stove.

When AccuWeather Senior Meteorologist Jason Nicholls puts the hot can in the ice water, the steam inside the can quickly cools and condenses into water. That lowers the pressure inside the can so much that the air pressure outside crushes it.

🔬 April 28 - Weather Lab: A dam that holds back cold air?

You may not know it, but many of you may have seen something that acts like a dam for cold air before. It’s not the type of dam that we’ve talked about before – it’s something that has been around since the Ice Age. What are we talking about?

Mountains!

There are times when cold air gets stuck up against the side of a mountain range, such as the east side of the Appalachian and Rocky mountains in the United States.

Time to pull out your dictionary of meteorology terms – this is called cold air damming, and the key to this dam is that cold air is denser than warm air. What does that mean? Let’s find out with this activity you can do at home (just get help from an adult as hot water is involved):

In the wintertime, cold air damming can lead to a snow day for some lucky kids – unless warm air flows over the cold air like in the activity above. If that happens, there can be ice instead of snow, and that’s not fun when you want to make a snowman!

🎓April 28 - AP class: Outsmart Jeopardy! contestants

We will start this class with a pop-quiz – what is the red weather feature shown in the graphic below?

If you said a warm front, you would have outsmarted three Jeopardy! contestants during a 2015 episode! During that game, contestants were shown a similar graphic and none of them knew the answer, an occasion known as a "triple stumper."

Cold fronts are one of the most recognized features on a weather map, but warm fronts can be on weather maps just as often.

So what is a warm front? A warm front marks the edge of cold air leaving an area with warmer air to follow. On the other hand, a cold front marks the edge of colder air sweeping in and replacing warmer air ahead of it.

Stay tuned for Final Jeopardy!

📝 April 23 - Pop quiz! Can you get a sunburn on a cool, sunny April day?

If you answered no, would you have said yes if the month was August and not April?

Actually, you can get a sunburn on a cool, sunny day in both April and August. The outside air temperature has nothing to do with getting a sunburn. It is more about what month it is and how strong the sun is.

The strength of the sun’s rays reaching you are as strong this time of year as they are in mid- to late-August – meaning that you are just as easy to get a sunburn now as later in the summer.

“It is possible to get a sunburn on a sunny day with a temperature of 40 F (4 C) as well as a sunny day with a temperature of 80 F (27 C),” according to AccuWeather Senior Meteorologist Alex Sosnowski.

It’s even possible to get sunburnt in the winter, especially at high elevations!

The above pop quiz is more for those of you living in the Northern Hemisphere. It’s fall for our friends south of the equator. They need to worry about getting a sunburn on a cool, sunny spring day in October.

🎭 April 23 - Story Time: This upside down cloud looks like a cow’s udder

You know how clouds form, right? Most clouds form when air rises, cools and condenses. However, there is one cloud that wants to be different and form backwards – that’s mammatus clouds, and they look like upside-down clouds too (check it out below)!

A close-up view of the mammatus clouds over Lubbock, Texas, during the summer of 2019. (Instagram/jtphil32)

“Mammatus clouds develop when air sinks,” AccuWeather Meteorologist and Digital Journalist Brian Lada explains. “The sinking air must be cooler than the air around it and have a high liquid water or ice content.”

Since the air is sinking (moving from up high in the sky to the ground), you can see why the clouds bubble downward – opposite of puffy cumulus or thunderstorm clouds that tower high in the sky! The unique look of mammatus clouds is how they got their name – do you agree that they resemble cows' udders?

Mammatus clouds are typically seen underneath a thunderstorm’s anvil (its top). Many people think that mammatus clouds mean a tornado is approaching. More often than not, it’s the opposite – these clouds form when a thunderstorm is weakening.

🎨 April 20 - Art Class: The case of the disappearing meteorologist

If you watch your favorite meteorologist on TV every day, you may notice that they never wear green. Why is that? AccuWeather On-Air Meteorologist Geoff Cornish solves this mystery, and it’s not as simple as that meteorologists hate the color green!

“Wait a minute, I’ve seen some meteorologists on the AccuWeather Television Network wearing green!” – is that what you are thinking? While meteorologists stand in front of a green screen at most television stations, the main studio at AccuWeather is set up differently:

🔬 April 16 – Weather Lab: Time to make rain gauges

Measuring snowfall is as easy as sticking a ruler into the ground – but the same can’t be done with rain. Instead, meteorologists use a rain gauge to record how much rain has fallen.

You can make your own rain gauge at home with a clear cylinder, masking tape, ruler, and pen. If you are having trouble finding a clear cylinder, like the ice tea pitcher shown in the video below, ask your parents if they wouldn’t mind cutting a soda or water bottle in half. As long as they are okay with it, that works too!

Once you build the rain gauge, watch for any rain in the forecast and record how much falls. Be sure to put something around the rain gauge to provide it support so it doesn’t get knocked over by any wind.

📓 April 16 – Homework: Ahh, the smell of rain ... but what are you actually smelling?

For your homework this weekend – if it rains in your area, go outside and take a deep breath through your nose. Does it smell nice? So many people like that smell that there are rain-scented laundry detergents and candles. It may surprise you that you aren’t really smelling raindrops. You are actually getting a whiff of dirt, worms and other things in the ground.

Here’s another big word to impress your parents and teachers with – petrichor. That’s the scent that fills the air as raindrops hit the ground. It’s caused by oils from plants, mainly leaves, that settle onto soils or pavement over time. The more time that passes between rain events, the more the oil will build up and the stronger the scent.

Don’t forget when you head outside to smell the rain, grab an umbrella or raincoat or you’ll get soaked!

📚 April 13 - Study Hall: Why are there so many earthworms after it rains?

Have you ever taken a walk after a soaking rainfall and had to avoid stepping on earthworms? Earthworms live in the dirt, so why do they come out of the ground after it rains?

If the ground gets too soggy with rain water, the earthworms will drown and die. Researchers from Penn State University say that the worms come out of the ground to get more oxygen.

As more earthworms come out of the ground, the more the air will smell like them. If someone says to you, “Ahh, the smell of rain is so nice,” be sure to tell them that they are just catching a whiff of dirt, worms or whatever the raindrop hits on the ground.

(Photo/ John Shepard/iStock /Getty Images Plus)

🌎 April 13 – History Class: ‘Perfect storm of calm’ played role in sinking of the Titanic

The Titanic sank in the frigid waters of the northern Atlantic Ocean during the early morning hours on April 15, 1912, after striking an iceberg.

While we have discussed much about clouds lately, there was not a cloud in the sky that fateful night. Even the moon was absent. The stars, however, were shining so brightly that historian and Titanic expert Tim Maltin told AccuWeather that people on the Titanic could see what time it was on their watches!

This April 10, 1912, file photo shows the liner Titanic as it leaves Southampton, England, on her maiden voyage. (AP photo)

Maltin said that “it was a perfect storm of calm” that played a role in the sinking of the Titanic. Listen below to learn more about that night and how the weather system that impacted the Titanic also played a role at the first baseball game ever played in Fenway Park:

🔬 April 9 - Weather Lab: Time to spin up tornadoes at home

A lot of ingredients go into a real tornado forming, but making one at home is simple with just a few items. You will need water and two empty soda bottles that are the same size, plus food coloring and glitter if you want to have extra fun with this experiment. To make the two soda bottles hold together, ask an adult to grab a large nail and hammer (or a drill with a half-inch drill bit will work) and duct tape.

AccuWeather Senior Meteorologist Jason Nicholls shows us how to put everything together and spin up our own tornado in the video below!

📓 April 9 – Homework: Ready, set, go – tornado shelter drill

The time to know what to do if a tornado threatens your home is not when the AccuWeather app says a tornado is coming, but right now. For your homework, practice with your family (pets included!) going to your tornado shelter.

“The basement [in places that are] away from windows, an interior stairwell or interior bathroom,” AccuWeather Meteorologist and Emergency Preparedness Specialist Becky DePodwin said for the best locations to shelter during a tornado. Some people believe that the southwest corner of a basement is the safest spot – that is a myth. Seeking shelter in a bathtub is a good option.

Go to the lowest floor of your home or building if you don’t have a basement. Don’t forget that mobile homes, along with vehicles, are not safe places to be during a tornado.

(AP Photo/J. Pat Carter)

Regardless of where your tornado shelter will be, be sure to put a flashlight, bottled water, closed-toed shoes and a blanket there when a tornado watch is issued. The blanket can shield you from flying debris. Shoes will protect your feet if you have to walk through any damage.

🔎 April 6 - Show & Tell: Human-sized tornado machine!

AccuWeather Senior Meteorologist Bob Smerbeck doesn’t have to leave his home to see a tornado – he just goes down to his basement and turns on his tornado machine!

Bob built the machine to look at how tornadoes form. This isn’t the simple experiment we did earlier to spin up a tornado with soda bottles and water. Bob spent three months making this machine – using a hair dryer, pipes, fan and a vaporizer.

How does Bob’s tornado compare to a real one? Many real tornadoes can grow up to a mile wide (the record widest is 2.6 miles) and these enormous twisters can damage or destroy many things in their paths. The one you see in the machine is about an inch wide and doesn’t create a mess in Bob’s basement – Mrs. Smerbeck is happy about that!

🎨 April 6 - Art Class: Weather has pirate hooks, and it’s no laughing matter

Have you ever dressed up like a pirate for Halloween and had a hook on your hand? While that was fun, it is no laughing matter when you see a pirate’s hook on weather radar.

A tornado-producing thunderstorm near Birmingham, Alabama, on April 27, 2011. (Image/GR2Analyst)

Look at the image above – it definitely looks like a hook, right? Meteorologists don’t call that a pirate’s hook, but a hook echo – a clear sign on radar that a tornado is on the ground.

Powerful thunderstorms that produce a tornado need warm, moist air to survive, and you can see that air rushing into the thunderstorm on radar – that’s the gap in the colors just above the tornado. Rain wrapping around the back of the thunderstorm to the tornado completes the hook.

There are times when the radar sees more than rain with a tornado. It can also tell if the tornado has debris spinning around it after it struck trees and buildings – that’s a worrisome sight for meteorologists.