Hulton Archive / Staff
Hulton Archive / Staff

5 Record-Breaking Extreme Weather Events in the U.S.

Hulton Archive / Staff
Hulton Archive / Staff

As a rule, bringing weather up in conversation is considered boring. Most of us in the U.S. infrequently experience truly extreme weather: Even when suffering through intense storms, heat waves, or bitter cold, our discomfort isn’t usually offset by bragging rights. That’s because most weather records are made in far-off locations. But there are a few truly astonishing exceptions where records were set closer to home.  


Image credit: Scott Patterson via Flickr// CC BY-NC 2.0

Just about every summer features a thunderstorm with what seems like the heaviest rain you’ve ever seen. Dark skies give way to a downpour that falls so fast that it’s hard to see more than a few feet down the road. But not even the heaviest rain you’ve ever seen can come close to the inundation in Unionville, Maryland, on July 4, 1956.

On that day, a gauge in this western Maryland town recorded 1.23 inches of rain in just one minute. That kind of sudden deluge is almost unimaginable, but scientists studied the gauge and found it to be in fine working order between 3:23 p.m. and 3:24 p.m. on that hot, humid afternoon. It’s even more impressive that the thunderstorm that produced this record rainfall wasn’t part of a tropical storm or hurricane—it appears to have been an everyday summer storm.


A destructive tornado can tear apart a home in an instant. When extreme winds rip apart a building, the debris scatters, sometimes for miles, usually never to be found by its original owner again. Every once in a while, though, far-flung wreckage can be traced back to where it originated.

Such was the case in Stockton, Kansas, on April 11, 1991, after an F3 tornado tore through the town, damaging and destroying several homes in the rural community. After the storm passed through, someone found a personal check from Stockton all the way in Winnetoon, Nebraska—an astounding 223 miles away.

Lightweight debris—things like leaves, insulation, and personal checks—frequently get lofted high enough into a thunderstorm that they get caught in strong upper-level winds, traveling dozens (if not hundreds) of miles downwind. But we usually don’t see tornado debris travel quite that far—nor are we usually able to pinpoint its origin with such ease.


The World Meteorological Organization recently certified two shocking lightning records for the history books: the longest lightning bolt and longest duration lightning bolt ever recorded. There are hundreds of recording stations all over the globe to measure where lightning strikes, and meteorologists can use the data from these stations to tell how long the lightning flash lasted and how long the bolt itself stretched.

Scientists used data from seven such recording stations to find that a 199.5-mile-long lightning bolt lit up the sky over Oklahoma on June 20, 2007, stretching from east to west across more than half of the large, flat state. That’s officially the longest lightning bolt ever recorded—a brand-new record that’s waiting to be broken by another enterprising storm in the future.

A few years later, the longest-duration lightning bolt ever recorded flickered in the sky over southern France on August 30, 2012. Most lightning only lasts for a fraction of a second, but this particular flash stretched nearly 100 miles across the southern Alps near Marseille, lasting for an astonishing 7.74 seconds.


How appropriate: The fastest temperature drop ever officially recorded plummeted the mercury in Rapid City, South Dakota on January 10, 1911. Life on the Plains can be rough during the winter. The flat land allows warm air to surge from the south one day but frigid air to dip from the north the next, resulting in wild temperature swings that happen frequently during the cooler months of the year.

That’s what happened in 1911. Dr. Walter Lyons records in The Handy Weather Answer Book that the official weather station in Rapid City measured a temperature of 55°F at 7:00 a.m. on January 10, just minutes before an intense cold front plowed through the tiny town. Fifteen minutes later, the temperature fell to just 8°F—representing a historic 47°F drop in the outside air temperature in the same time it takes to boil a pot of pasta. More than 30 years later, in 1943, the nearby town of Spearfish would set a related record, for fastest temperature increase: 49°F in just two minutes.


The record-breaking hailstone that fell in Vivian, South Dakota. Image credit: National Weather Service

Another winner for the Mount Rushmore State. Any chunk of ice hurtling toward the ground is too large when you’re worried about your car, home, or crops. But some thunderstorms are able to grow so strong they create hailstones larger than baseballs—and a handful of thunderstorms produce chunks of ice large enough to leave craters in the ground.

The largest hailstone ever recorded fell in Vivian, South Dakota, on the afternoon of July 23, 2010. The hailstone was nearly the size of a volleyball, measuring 8 inches in diameter and weighing almost 2 pounds. Meteorologists estimate that updraft winds—the unstable air shooting up into the storm—had to have blown 160–180 mph to sustain the weight of such a massive hailstone.

Days Inn
Days Inn's New LED Umbrella Makes Gloomy Days Sunnier
Days Inn
Days Inn

Taking a walk outside is a quick way to feel better—unless it's raining. If you're someone who loves sunshine and clear skies, you may use gloomy weather as an excuse to lock yourself indoors for the whole day. A new type of umbrella from Days Inn may prompt you to reconsider. The hotel chain's Days InnBrella uses built-in LED strips to provide you with a personal patch of light even on the dreariest days.

The new product takes the umbrella's timelessly practical design one step further. As the fabric keeps you dry, the interior lights each generate 4000 LUX (a unit used to measure the amount of light striking a surface). It's no replacement for bright sunlight, but its glow should hopefully give you the mood boost you need the next time you're walking in the rain.

Woman with illuminated umbrella.
Days Inn

If you're over 18 and have a Twitter account, you're eligible to win a free Days InnBrella of your own. Just retweet this tweet from Days Inn before June 26 to enter the contest. The five winners will be selected on June 27.

Days Inn isn't the first brand to give the classic umbrella an upgrade. KAZbrella stays drip-free by closing inside-out, and Oombrella gives weather forecasts and alerts you when you leave it behind.

Why Does the Sky Look Green Before a Tornado?

A common bit of folklore from tornado-prone parts of the U.S. says that when the skies start taking on an emerald hue, it's time to run inside. But why do tornadoes tend to spawn green skies in the first place? As SciShow's Michael Aranda explains, the answer has to do with the way water droplets reflect the colors of the light spectrum.

During the day, the sky is usually blue because the shorter, bluer end of the light spectrum bounces off air molecules better than than redder, longer-wavelength light. Conditions change during the sunset (and sunrise), when sunlight has to travel through more air, and when storms are forming, which means there are more water droplets around.

Tornadoes forming later in the day, around sunset, do a great job of reflecting the green part of the light spectrum that's usually hidden in a sunset because of the water droplets in the clouds, which bounce green light into our eyes. But that doesn't necessarily mean a twister is coming—it could just mean a lot of rain is in the forecast. Either way, heading inside is probably a good idea.

For the full details on how water and light conspire to turn the sky green before a storm, check out the SciShow video below.


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