What Are Microbursts?

NOAA Legacy Photo ERL/WPL, Flickr // CC BY 2.0
NOAA Legacy Photo ERL/WPL, Flickr // CC BY 2.0

It's monsoon season in the American Southwest. Daily thunderstorms popping up over a dry landscape provide countless opportunities for passersby to take pictures and videos of the torrents as they bring an annual dose of rain to the otherwise parched desert. One of the more striking features of these desert thunderstorms is a term you see all over social media: microbursts. These destructive wind events can be terrifying to live through, but beautiful to watch from afar.

A microburst is a downward burst of damaging winds, rain, and hail that literally drops out of the bottom of a thunderstorm. A microburst occurs over a relatively tiny area; the extent of the strong winds is usually only a mile or two wide. From a distance, a microburst can look like a water balloon falling toward the ground, splashing outward upon impact like a mushroom cloud unfolding in reverse. Pictured above is a microburst with a classic water balloon appearance, spotted by NOAA scientists around 1980.

Meteorologists didn't give much thought to this phenomenon until the 1970s, when Dr. Ted Fujita—famous for his pioneering research into tornado intensity that led to the creation of the Fujita Scale—started to study the distinct pattern of damage that these windstorms leave behind.

You don't want to find yourself beneath a microburst. Just as with other destructive thunderstorms, some folks who experience these damaging winds insist that they really lived through a tornado. These winds come on suddenly, often going from a gentle breeze to a nightmarish windstorm within seconds, and can blow away anything not nailed down to the ground. Winds in a microburst can easily exceed 60 mph—but the strongest microbursts mimic the intensity of weak tornadoes, with winds peaking above 100 mph in some spots.

Well-developed thunderstorm with microburst, circa 1980NOAA Legacy Photo ERL/WPL, Flickr // CC BY 2.0

Different parts of the United States are prone to different types of microbursts. A wet microburst occurs with heavy rain or hail; these are common in humid areas like the southeast. A dry microburst, on the other hand, isn't accompanied by any precipitation at all; blowing dust and debris at the surface is often the only indication one of these events is occurring. Dry microbursts are common in places where there's not much humidity, like higher elevations or the desert.

Microbursts form due to two factors: evaporation and the weight of rain and hail. Evaporation is a cooling process; when liquid water turns to water vapor, it absorbs heat and cools the air around it. If dry air starts to invade the environment in or around a thunderstorm, it can cause rain to evaporate and leave behind large sections of air that are suddenly cooler than their surroundings. This less dense air sinks toward the ground, falling faster and faster until impact. The weight of the rain and hail also contributes to the speed of a microburst. Water is heavy, and that weight plays a big role in dragging cool air down from a thunderstorm. The two processes combined help create microbursts.

The biggest danger posed by microbursts is their sudden, sneaky formation. Microbursts happened with almost no notice at all until just the last decade or two. You didn't know it was happening until it happened. This surprise downward burst of winds and resulting wind shear can be potentially lethal to aircraft that are taking off and landing during thunderstorms. Microbursts have contributed to numerous airplane crashes over the years, killing hundreds of people.

We've gotten much better at detecting microbursts. The prevalence of Doppler weather radar across the United States, including smaller radars installed near most major airports, allows meteorologists to give people on the ground and in airplanes a little bit of advance notice before a microburst occurs. Wind shear detection systems both on the ground and installed in aircraft have also helped tremendously when pilots are flying into nasty weather.

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12 Perfectly Spooky Halloween Decorations Under $25

Amazon/shopDisney
Amazon/shopDisney

Halloween is right around the corner—which means it’s officially time to bring out the jack-o'-lanterns, watch scary movies, buy your costume(s), and hang up your festive decorations. Although there are thousands of decorations to choose from, you don’t have to blow your budget while decking out your house or apartment in honor of the spooky season this year. With a little guidance, you'll find plenty of ways to create the perfect ambiance at home without going for broke. (And best of all, you can put the money you saved toward extra Halloween candy to stash away.)

From giant spiders to hanging ghosts and lawn decorations, here are a few of our favorite props under $25.

1. Halloween Pillow Covers (4-Pack); $17

ZJHAI/Amazon

These adorable Halloween-themed pillowcases make the perfect accessory for any couch, sofa, or mattress. Made with thick linen fabric, these are durable, sturdy, and designed to last for seasons to come. (Tip: To prevent the zipper from breaking, fold the pillow in half before inserting.)

Buy it: Amazon

2. Black Lace Spiderweb Fireplace Mantle; $12

Aerwo/Amazon

This versatile spiderweb prop is made with 100-percent polyester, and its knit lace spiderweb pattern adds a spooky touch to any home. Display it on your doorway, across your fireplace mantel, or atop your table. (It also makes a great backdrop for Halloween photo ops.)

Buy it: Amazon

3. Statement Halloween Signs; $16

Dazonge/Amazon

These festive, statement-making banners come pre-assembled, making them incredibly easy to install. They’re also weather-resistant and washable for both outdoor and indoor use. Use tape, push-pins, or weights to prevent the signs from blowing away.

Buy it: Amazon

4. Jack Skellington and Sally Plush Dolls; $23 (Each)

Disney

Celebrate your favorite holiday with a pair of adorable Jack Skellington and Sally plush dolls from Tim Burton’s The Nightmare Before Christmas. Jack stands at 28 inches tall, while Sally is a bit shorter at 21 inches. Set them up on your sofa or against the window sill for all to see.

Buy them: Disney Shop (Jack and Sally)

5. Halloween Zombie Groundbreaker; $22

Joyin/Amazon

This spooktacular zombie lawn decoration is sure to scare all of your friends, family, and neighbors alike. Made with a combination of latex, plastic, and fabric, this durable Halloween prop is sure to last for years to come.

Buy it: Amazon

6. Hanging Ghost Decoration; $14

Moon Boat/Amazon

Drape this handmade, 14-foot-long hanging ghost decoration over your porch, doorway, or window. You can also hang it outdoors over a tree or a (very tall) bush. And, since it comes pre-assembled, you won’t have to waste time constructing it yourself.

Buy it: Amazon

7. Two-Piece Hanging Ghost Set; $17

GeeFuun/Amazon

This pair of ghosts adds a whimsical touch to any home. While they’re not “scary,” per se, they certainly are adorable. Display them in your front yard, on your porch, on a lamppost, or a tree. To hang, simply tie the ribbons and bend the wires, arms, and tails.

Buy it: Amazon

8. Pumpkin String Lights; $19

Eurus Home/Amazon

Not only are these solar-powered, 33-foot-long LED string lights good for the environment, they’re also incredibly easy to install (no long, tangly power cable chords necessary). Since they’re waterproof, you can use them both indoors and outdoors. Choose from eight different light settings, including twinkling, flashing, fading, and more.

Buy it: Amazon

9. Inflatable Ghost; $22

Joiedomi/Amazon

This adorable inflatable ghost (which dons a cute-as-can-be wizard hat!) features built-in LED lights and sandbags to help it stay sturdy. It also comes complete with a plug, extended cords, ground stakes, and fastened ropes. Simply plug it in and watch it magically inflate within just a few minutes.

Buy it: Amazon

10. Graveyard Tombstones; $17

meiguisha/Amazon

Turn your front lawn into a graveyard with this six-piece set. Each tombstone is made with foam and designed to add a touch of spookiness to your space. To install, insert one holder into the bottom of the tombstone, and one into the soil. You can use these indoors, as well.

Buy it: Amazon

11. 10-Piece Skeleton Set; $24

Fun Little Toys/Amazon

This skeleton set includes a skull, hands and arms, and legs and feet—plus five stakes to hold everything in place. Each “bone” and “joint” is flexible, allowing you to prop the skeleton into different frighteningly fun poses. Simply place the stakes into the bone socket and turn clockwise.

Buy it: Amazon

12. Outdoor Spider Web; $18

amenon/Amazon

This giant, ultra-stretchy spider web spans a whopping 23 feet. It also includes a 30-inch black spider, 20 pieces of fake spiders, one hook, and one nail. Its thick polyester rope—combined with the sturdy stakes—allows the spider web to stay in place all season long. Place the hook on a wall or tree, and expand the web using the stakes.

Buy it: Amazon

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Why Do We Say 'Trick or Treat' on Halloween?

"Give us candy, or else!"
"Give us candy, or else!"
kali9/iStock via Getty Images

Each Halloween, hordes of costumed kids trudge from door to door exclaiming the same phrase at each stop: “Trick or treat!” It’s really a treat-only affair, since adults always shell out candy and children rarely have tricks up their sleeves (except perhaps for those dressed as magicians). In other words, they may as well save half a breath and simply shout “Treat!”

So, where did the term come from?

Halloween Hijinks

Halloween wasn’t always about cosplay and chocolate bars. During the 19th century, Irish and Scottish children celebrated the holiday by wreaking (mostly harmless) havoc on their neighbors—jamming hot cabbage into a keyhole to stink up someone’s house, frightening passersby with turnips carved to look ghoulish, etc.

According to History.com, kids didn’t give up that annual mischief when they immigrated to the U.S., and Americans happily co-opted the tradition. Toppled outhouses and trampled vegetable gardens soon gave way to more violent hijinks—like the time a Kansas woman almost died in a car crash after kids rubbed candle wax on streetcar tracks, for example—and these pranks escalated during the Great Depression.

Almost as terrifying as a turnip.London Stereoscopic Company/Hulton Archive/Getty Images

In short, tricks were a huge part of Halloween throughout the early 20th century. So, too, were treats. For All Souls’ Day in the Middle Ages, people went door-to-door offering prayers for the dead in exchange for food or money, a tradition known as souling. A similar custom from 19th-century Scotland, called guising, entailed exchanging jokes or songs for goodies. While it’s not proven that modern treat-begging is directly derived from either souling or guising, the practice of visiting your neighbors for an edible handout around Halloween has existed in some form or another for centuries.

Canada Coins a Catchphrase

With tricks and treats on everyone’s minds come October, it was only a matter of time before someone combined them into a single catchphrase. Based on the earliest known written references to trick or treat, this may have happened in Canada during the 1920s. As Merriam-Webster reports, a Saskatchewan newspaper first mentioned the words together in an article from 1923. “Hallowe’en passed off very quietly here,” it read. "'Treats' not 'tricks' were the order of the evening." By 1927, young trick-or-treaters had adopted the phrase themselves.

"Hallowe’en provided an opportunity for real strenuous fun," Alberta’s Lethbridge Herald reported in 1927. "No real damage was done except to the temper of some who had to hunt for wagon wheels, gates, wagons, barrels, etc., much of which decorated the front street. The youthful tormentors were at back door and front demanding edible plunder by the word 'trick or treat,' to which the inmates gladly responded and sent the robbers away rejoicing."

The phrase appeared in Michigan’s Bay City Times the following year, describing how children uttered "the fatal ultimatum 'Tricks or treats!'" to blackmail their neighbors into handing out sweets.

Donald Duck's Endorsement

Sugar rationing brought trick-or-treating to a temporary halt during World War II, but the tradition (and the phrase itself) had gained popularity once again by the early 1950s—with some help from candy companies and a few beloved pop culture characters. Charles Schulz depicted the Peanuts gang cavorting around town in costume for a Halloween comic strip in 1951; and Huey, Dewey, and Louie got to go trick-or-treating in a 1952 Donald Duck cartoon titled Trick or Treat.

Fortunately, the treat part of the phrase has thoroughly overtaken the trick part. But if you stuff rank cabbage in your neighbor’s keyhole this Halloween, we won’t tell.

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