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Can lightning hurt you while you're inside? What's the true shape of a rainbow? And is there a chance that snow isn't actually white? Join host Justin Dodd as he unpacks some myths and misconceptions about weather.
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Misconceptions About Weather | Mental Floss
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0:00
If we asked you to grab your box of Crayolas and draw a rainbow right now, you'd draw
0:04
Roy G. Biv in an arc shape, right? I mean, so would I. But the idea of rainbows that we all
0:10
grew up with since we were preschoolers is not quite right. Rainbows are an optical illusion
0:16
caused by light refracted and reflected through water droplets. When we're on the ground
0:21
we can only see the light that's above the horizon, thus the arc shape. But scientifically
0:27
rainbows are circular. We just can't usually see the whole thing from our vantage point
0:31
If you spot a rainbow from an airplane, though, you can sometimes see the complete circular shape
0:36
Hi, I'm Justin Dodd, and the true shape of rainbows is just one of many weather misconceptions
0:42
we'll be broadcasting today. So grab your raincoat and snow boots, because we've got a brainstorm of brewing
0:57
Lightning can't hurt you if you're inside. Oh no, there's a nasty storm happening
1:03
Just to be safe, you decide to head indoors. Good instinct, but just because you're inside doesn't mean you're 100% safe
1:09
According to the CDC, one third of lightning strikes actually occur indoors
1:14
Lightning can travel through electrical systems, plumbing, and metal bars and concrete or flooring
1:19
so just because you're inside does not mean you're safe. To decrease your chances of an indoor lightning strike
1:25
the CDC recommends avoiding bathing, showering, or washing dishes during a storm. Another no-no
1:31
using anything connected to an electrical outlet, including your TV and computer
1:36
If you still have a corded phone at home, do not use it either. And finally, avoid windows
1:42
doors, porches, and concrete walls or flooring. I guess that doesn't leave a ton of safe indoor
1:47
activities on a rainy day, but hey, I'm always looking for an excuse to read a book. But, you
1:52
know, by candlelight. You should open a window in a tornado. Once upon a time, it was believed that
1:59
opening a window or two while a tornado loomed nearby could actually save your home. The idea
2:04
was that the open windows would equalize the air pressure and prevent strong winds from ripping the
2:10
roof from the house. This theory has since been debunked. Researchers found that opening windows
2:15
actually kind of does the opposite, causing the force of the twister to push up on the roof
2:22
It also puts the folks in the house at additional risk for being struck by flying debris
2:27
This also holds true for hurricanes. Cracking a window isn't going to do anything but let some more water in
2:34
so keep those windows closed for everybody's sake. Going out in the cold with wet hair will give you a cold
2:41
Your mom and grandma might have told you this one, but it is a myth
2:45
Except for the parts that aren't. Colds are caused by viruses, and those viruses are spread through contact with the virus, not your damp locks
2:56
Except there are illnesses that are more common during winter. That is not a myth
3:01
And there have been studies that find increased visits and hospitalizations for pneumonia and the flu following cold snaps
3:09
Why that is is a subject of very active research. One popular theory is that during winter people gather in enclosed spaces for prolonged periods of time But more recently there been research into how the cold weather might actually suppress your immune system So while it true that no virus equals no cold
3:28
no matter what the thermometer says, it's still a good idea to not get overly chilled
3:34
Snow is white. I'm dreaming of a translucent Christmas doesn't have quite the same ring to it
3:41
But if Bing Crosby was being scientifically accurate, those would have been the lyrics. The reason snow appears to be white is because of the way the light
3:50
is reflected and scattered by the millions of tiny ice crystals and the air between the crystals
3:56
with very little being absorbed. Think about an ice cube from your fridge. That's fairly
4:02
translucent, but shaved ice is white. Snow doesn't always appear to be white. Algae can make the snow
4:09
seem pink, which is also known as watermelon snow. It can also present as blue, usually in a deep
4:15
snowpack, or if you're looking down into the crevasse of a glacier, as we all often do. That's
4:21
because there's often not as many air bubbles to help with the scattering of the light, but also
4:26
because ice doesn't reflect and scatter all colors evenly. It absorbs more red than it does blue
4:32
Not enough that you'd notice in a snowdrift, but in a large enough glacier, you can get a little
4:37
blue in there. Of course, there's also yellow snow, but that phenomenon isn't quite as fascinating
4:45
Highway and interstate overpasses provide good shelter from tornadoes. You've probably heard that
4:51
if you find yourself driving when a tornado strikes, the best thing to do is seek shelter
4:55
under an overpass. And while that was the thinking at one point in time, newer research has shown
5:01
that you should actually do the exact opposite. Avoid overpasses and bridges at all costs
5:07
The CDC says if you find yourself in your car and absolutely cannot make it to a proper tornado
5:13
shelter, the better than nothing but definitely not good option is to get down in your vehicle
5:19
and cover your head and neck, or leave your car entirely to find low-lying ground like a ditch or
5:26
ravine. So what makes an overpass a bad choice? Several things, it turns out. First, FEMA calls
5:32
the area underneath and downstream of the overpass a debris deposition zone, and stopping under a
5:39
bridge can make your car a target for flying debris. Even small things like soda bottles can
5:44
cause severe damage when they're whipping around at 100 miles per hour. Second, cars clustering
5:50
under a bridge can create a roadblock for other drivers, including emergency vehicles trying to
5:55
get through to help victims. And finally, wind velocity under the overpass can actually become
6:01
concentrated into a funnel, making it even more of a danger than just the regular highway
6:07
Look, Twister is an awesome movie, but it might not be 100% accurate
6:12
Blue skies mean you're safe from lightning. Clear blue skies and no rain may make you feel
6:18
safe outside, but if there's a storm in the area, you could still be at risk. Bolts from the blue
6:24
are cloud-to-ground lightning strikes that usually come from the backside of a storm cloud
6:29
and travel up to 25 miles away through clear air before striking the ground
6:34
The large distance the lightning can move from the cloud makes it appear the lightning struck out of seemingly nowhere which is why the National Weather Service recommends waiting at least 30 minutes after rain has passed to resume outdoor activities
6:48
If it were perfectly clear above me and a random lightning strike traveled 20 miles just to
6:53
strike me, I would really believe I had upset Zeus personally. Auroras only happen in cold temperatures
7:01
Good news if you're adverse to freezing temps but also have seeing the northern lights on your bucket list
7:07
You do not have to get icicles on your eyelashes to see them. The northern lights are often best seen closer to the North Pole
7:14
which people obviously associate with very cold temperatures, making it easy to assume that auroras and the freezing cold go hand in hand
7:23
In fact, the best time for looking for auroras are during the spring and autumnal equinoxes
7:28
which are far from the depths of winter. You can even catch Aurora Borealis in the middle of summer with a little luck and a little timing
7:36
The best viewing tips go sometime between August and April, the darkest part of the year
7:41
and aim for 10 p.m. to 2 a.m., the darkest part of the night
7:45
The northern lights are your only chance to see auroras. And as an aside, don't worry if climates like Canada, Alaska, Norway, and Finland aren't at the top of your travel list
7:56
You can also see auroras in the southern part of the hemisphere. Called Aurora Australis, they're, well, they're not as easy to see as the Aurora Borealis simply because there's just not that much inhabited land really far south, not called Antarctica
8:13
Tasmania is usually considered the best spot to see the southern lights, but according to the BBC
8:19
although people associate auroras with streaks of color lighting up the sky
8:23
In Tasmania, you'll likely see a white light without a camera, perhaps with some colored glow around it
8:30
unless there's enough cosmic activity to make the aurora big enough. So make sure you know what you're looking for if you go southern lights hunting
8:39
A hundred-year storm only happens once a century. The phrase, hundred-year storm or hundred-year hurricane, certainly sounds self-explanatory, but it's a little misleading
8:51
According to the National Weather Service, it doesn't mean that a hurricane of a certain magnitude only occurs once a century
8:58
What it essentially means is that the chance of it happening is very small, i.e. 1% per year
9:05
Think about rolling dice. The odds of rolling a 1 are 1 in 6
9:10
But if you roll a dice six times, there's no guarantee you will roll a 1
9:14
If you've ever played dice games, you know this. It's unlikely, but you might also get six 1s in a row
9:21
But over hundreds and thousands of rolls, you'd expect to roll a one about a sixth of the time
9:26
Hundred-year storms are a little more statistically complicated, but the general idea is the same
9:31
Over sufficiently long periods of time, you'd expect a hundred-year storm to happen in about 1% of years
9:39
But like rolling two ones in a row, if you've experienced a hundred-year storm or a hundred-year hurricane in your lifetime
9:46
don't breathe a sigh of relief. Unfortunately, you're still on the hook
9:51
You should tape your windows before high winds or a big storm. During pre news footage you often see people preparing for hurricanes by taping or boarding up their windows One of these methods is recommended and the other is actually quite dangerous The Federal Alliance for Safe Homes says that using hurricane shutters or properly
10:11
installed makeshift shutters made from sufficiently thick exterior-grade plywood is the only way to go
10:19
Taping windows is not only ineffective when it comes to preventing shattering
10:22
it actually makes windows more deadly. Instead of shattering into tiny pieces
10:28
taped windows have a tendency to break into larger, deadlier shards. In fact, the first reported death
10:34
from Hurricane Charlie in 2004 was a person who was standing behind
10:38
a sliding glass window that had been taped. Thunder and lightning only happen during rainstorms
10:44
It can, and it does, thunder and lightning during snowstorms, but not super often
10:51
thundersnow is a relatively rare and under-researched event. Scientists think it's caused by the same things that cause a normal thunderstorm
11:00
That is, moist and warm air near the Earth's surface rises, condenses to form clouds filled with super-cooled water, ice crystals, and hail
11:10
It all rattles around inside the cloud, creating an electrical charge and lightning and thunder
11:15
But during thundersnow, you may not see the lightning because it tends to generate the cloud-to-cloud kind, not the cloud-to-ground kind
11:24
It's associated with heavy snowfall, typically six-plus inches in a day. And here's a myth that is true
11:32
Red sky at night, sailors delight. If you're an avid boater or maybe just the collector of old adages
11:38
you may have heard the saying, Red sky at night, sailors delight. Red skies in the morning, sailors take warning
11:44
It means that if the sky takes on a reddish hue while the sun is setting
11:48
there's fair weather ahead. Conversely, if the sky goes scarlet when the sun is rising
11:53
a storm may be a-brewin'. The saying goes back millennia, with a version of it even appearing
11:59
in the Bible. And that saying, surprisingly, is absolutely true in the mid-latitudes
12:05
according to Scientific American. And they explain it the best, saying, "...because the sun rises in the east and sets in the west, a rising sun in advance of an
12:15
approaching weather system would illuminate the approaching mid and high-level clouds to create a
12:21
red sky in the morning. Alternatively, if the sun is setting as a weather system exits and high
12:28
pressure is building, then the departing clouds would be illuminated. This would create a red sky
12:35
at night with fair weather to follow. What makes the skies appear red? Like snow, it has to do with
12:41
the way sunlight scatters, and also because of the high concentration of dirt, dust, and aerosol
12:48
in the lowest layers of the atmosphere during periods of high pressure. Now, occasionally
12:54
weather systems can move from south to north instead of the usual west to east. And in that
12:59
case, the saying doesn't really work. But hey, good to know sailors weren't just making up total
13:05
lies for the sake of a good rhyme. That's all the weather misconceptions we have for you today
13:11
Which one was most surprising to you? Let us know in the comments while I Google full circle rainbows for, you know, just a couple of hours
13:19
Thanks for watching, and I'll see you next time
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