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.

Microburst, circa 1980
Well-developed thunderstorm with microburst, circa 1980
NOAA 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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What's the Difference Between Tequila and Mezcal?

iStock.com/mediaphotos
iStock.com/mediaphotos

Aside from tacos, enchiladas, and other tasty tortilla-wrapped treats, tequila and mezcal are among some of Mexico’s best-known offerings in the food and beverage category. These tipples, made from the agave plant, are so embedded in the country’s culture that Mexico City even has a museum dedicated to the two drinks, and Jose Cuervo operates a "tequila train" to none other than the city of Tequila. These beverages can be used to make a variety of cocktails, from the tequila sunrise to the mezcalita, but unless you’re a bartender or a connoisseur of spirits, you might not know the difference between the two. Is mezcal just fancier tequila?

Not exactly. Tequila is a type of mezcal, but the reverse isn’t always true. It’s similar to the distinction between champagne and sparkling wine, in which the name of the beverage depends on whether it was produced in the Champagne region of France or elsewhere. While mezcal can be produced anywhere in Mexico, tequila is made in the Mexican state of Jalisco (though a few exceptions do apply).

Tequila and mezcal also differ in the ingredients from which they are derived. Mezcal can come from any of the dozens of agave plants—a type of desert succulent—that are grown throughout Mexico. Tequila is made specifically from blue agave and, depending on the variety and brand, a bottle will contain between 51 percent and 100 percent of the plant-based nectar. According to The Tierra Group, a wholesaler of agave products, blue agave nectar is especially sweet because it’s 80 percent fructose, per Mexico’s regulations.

Lastly, tequila and mezcal taste different because of the ways in which they are prepared. Mezcal tends to have a savory, smoky, earthy flavor because the agave hearts (or piñas) are left cooking for several days in a fire pit that has been lined with volcanic rock and covered with agave leaves and earth. The piñas destined to end up in tequila, on the other hand, are often cooked in a brick oven, then crushed up to extract the juice.

If you ever feel adventurous at the liquor store and decide to bring home a bottle of mezcal, just keep in mind that there’s a particular way to drink it. “The first mistake many people make is pouring mezcal in a shot glass and pouring it down their throat,” Chris Reyes, a mixologist at New York City’s Temerario bar and restaurant told Liquor.com. Instead, the spirit is best sipped in a clay cup known as a jicarita.

Some words of advice if you do go shopping for mezcal: If you ever see a worm at the bottom of the bottle, that means it’s probably not a very good mezcal, according to Reyes. By contrast, tequila bottles should never have worms in them (despite the common misconception). So if you’re looking to avoid invertebrate-infused concoctions at all costs, tequila is your best bet.

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Presidents Day vs. President's Day vs. Presidents' Day: Which One Is It?

iStock
iStock

Happy Presidents’ Day! Or is it President’s Day? Or Presidents Day? What you call the national holiday depends on where you are, who you’re honoring, and how you think we’re celebrating.

Saying "President’s Day" implies that the day belongs to a singular president, such as George Washington or Abraham Lincoln, whose birthdays are the basis for the holiday. On the other hand, referring to it as "Presidents’ Day" means that the day belongs to all of the presidents—that it’s their day collectively. Finally, calling the day "Presidents Day"—plural with no apostrophe—would indicate that we’re honoring all POTUSes past and present (yes, even Andrew Johnson), but that no one president actually owns the day.

You would think that in the 140 years since "Washington’s Birthday" was declared a holiday in 1879, someone would have officially declared a way to spell the day. But in fact, even the White House itself hasn’t chosen a single variation for its style guide. They spelled it “President’s Day” here and “Presidents’ Day” here.


Wikimedia Commons // Public Domain

Maybe that indecision comes from the fact that Presidents Day isn’t even a federal holiday. The federal holiday is technically still called “Washington’s Birthday,” and states can choose to call it whatever they want. Some states, like Iowa, don’t officially acknowledge the day at all. And the location of the punctuation mark is a moot point when individual states choose to call it something else entirely, like “George Washington’s Birthday and Daisy Gatson Bates Day” in Arkansas, or “Birthdays of George Washington and Thomas Jefferson” in Alabama. (Alabama loves to split birthday celebrations, by the way; the third Monday in January celebrates both Martin Luther King Jr. and Robert E. Lee.)

You can look to official grammar sources to declare the right way, but even they don’t agree. The AP Stylebook prefers “Presidents Day,” while Chicago Style uses “Presidents’ Day.”

The bottom line: There’s no rhyme or reason to any of it. Go with what feels right. And even then, if you’re in one of those states that has chosen to spell it “President’s Day”—Washington, for example—and you use one of the grammar book stylings instead, you’re still technically wrong.

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