Why the Weather on the Great Plains Is So Extreme

Brandi Simons/Getty Images
Brandi Simons/Getty Images

It can be tough to live on the Great Plains. The flat terrain gives way to breathtaking views of both land and sky, but the smooth, fertile land is both good fortune and a curse when it comes to the weather. Whether it's an enormous thunderstorm or a ferocious blizzard, there's rarely a dull day when it comes to weather in the middle of the country. Just what is it about the central United States that makes the weather there so extreme?

The unique geography that makes this part of the country so grand is what exposes it to some of the most extreme weather nature can produce. The Plains are bounded by the Rocky Mountains to the west, the Canadian Prairies to the north, and the Gulf of Mexico to the south. The tall, jagged mountains of the Rockies act like an atmospheric dam, forcing hot air from the south and cold air from the north to pool up over the Plains. This helps to trigger some of the most interesting weather in the world.

Most major weather events around the world are set in motion by jet streams, which are fast-moving currents of air that wrap around the planet. Straight, rigid jet streams don't result in much interesting weather, but things can get wild when the jet stream grows wavy. Sharp dips in the jet stream, called troughs, can cause low-pressure systems to develop at the surface.

When these troughs clear the Rocky Mountains in the western U.S., diverging winds in the upper atmosphere cause air to rise from the surface, leading to the development of a low-pressure system over the Plains. These lows can be the size of a single state or sprawl across the entire country from north to south. We see these storm systems most often during the winter and spring, when the jet stream is most active over the United States.

The flat land acts like an expressway, helping these fledgling low-pressure systems draw enormous amounts of tropical air from the south and, during the winter, extremely cold air from deep in the Arctic. The lack of natural obstacles allows this air to flow toward storm systems virtually unimpeded, which can lead to explosive thunderstorms during the warm months and powerful and bone-chilling blizzards during the winter.

This atmospheric expressway doesn't stop at precipitation; it's also why the central Plains can have brutal heat waves and bitter cold snaps. It's not uncommon for areas in the north-central United States to struggle to climb above 0°F for days at a time during the dead of winter, and it's similarly common for places like Oklahoma and Texas to see temperatures above 100°F for a week or longer during the summer's worst heat.

A Pile of Manure and a Heat Wave Combined to Cause Spain’s Worst Wildfire in 20 Years

Lumppini, iStock/Getty Images Plus
Lumppini, iStock/Getty Images Plus
A pile of manure in Spain ignited on June 27, sparking a wildfire that has torn through more than 10,000 acres of forest and other Catalonian landscapes, CNN reports. The manure combusted in part because of a scorching heat wave that has swept across Europe this week; temperatures in the affected region hit 104°F, and Germany, Poland, and the Czech Republic all reached record-breaking June temps. Catalan regional interior minister Miquel Buch reported that authorities believe the manure was improperly stored on a chicken farm in the village of La Torre de l’Espanyol, where it was exposed to the worst of the heat, according to NBC News. The wildfire—Spain’s most devastating in 20 years—is affecting the region just west of Tarragona, a port city that is best known for its Roman ruins, which is situated along the Balearic Sea about 60 miles southwest of Barcelona. [[{"fid":"315211","view_mode":"width-constrained-728","fields":{"format":"width-constrained-728","field_file_image_title_text[und][0][value]":false,"field_file_image_alt_text[und][0][value]":"Map of Catalonia, Spain","field_image_subhead[und][0][value]":"","field_image_subhead[und][0][format]":"unfiltered","field_caption[und][0][value]":"","field_caption[und][0][format]":"unfiltered","field_credits[und][0][value]":"PeterHermesFurian%2C%20iStock%2FGetty%20Images%20Plus","field_credits[und][0][format]":"unfiltered"},"type":"media","field_deltas":{"1":{"format":"width-constrained-728","field_file_image_title_text[und][0][value]":false,"field_file_image_alt_text[und][0][value]":"Map of Catalonia, Spain","field_image_subhead[und][0][value]":"","field_image_subhead[und][0][format]":"unfiltered","field_caption[und][0][value]":"","field_caption[und][0][format]":"unfiltered","field_credits[und][0][value]":"PeterHermesFurian%2C%20iStock%2FGetty%20Images%20Plus","field_credits[und][0][format]":"unfiltered"}},"link_text":false,"attributes":{"alt":"Map of Catalonia, Spain","height":728,"width":728,"class":"media-element file-width-constrained-728","data-delta":"1"}}]] The firefighting force includes about 350 firefighters, 12 fire engines, seven aircraft, two hydroplanes, and additional vehicles equipped with water tanks—all of which are techniques regularly used to fight massive blazes. Though high temperatures are expected to continue and the rough terrain itself is also a contributing factor in the rapid spread of the fire, the strong winds should soon abate; authorities have warned people to stay inside. Though more than 50 people have been evacuated from the area, no deaths have been reported thus far. While the spontaneous combustion of flammable materials like manure, hay, or compost is definitely possible, as evidenced by this situation, it’s not the most common way for wildfires to start. More common causes include lit cigarettes, unattended campfires, burning debris, and engine sparks. [h/t CNN]

Colorado Welcomed Summer With 2 Feet of Snow

Emmanuel Dunand/AFP/Getty Images
Emmanuel Dunand/AFP/Getty Images

While people in some parts of the country celebrated the first day of summer with barbecues and trips to the beach, residents of north and north-central Colorado had a snow day. Areas west of Denver—including Grand Lake, Aspen, and Steamboat Springs—experienced snow storms on summer solstice, with snowfall totaling nearly 2 feet at the highest elevations, CBS Denver reports.

Snow started falling in the Rocky Mountains the morning of Friday, June 21 and continued Sunday. Areas at ground level weren't cold enough to experience the unusual weather, but at elevations of 7000 feet and above, it looked like a winter wonderland. Steamboat Springs, a ski resort town in Colorado’s Yampa Valley, accumulated 20 inches of snow on the longest day of the year.

While Colorado mountain towns are used to seeing snow at odd times of year, the weekend's weather was still out of the ordinary. The average snowfall for Steamboat Springs in June is 0.1 inches. Prior to last Friday, it had been 91 years since a snowstorm hit the city in late June.

Snow has fallen in the Rockies later than average in six out of the past seven years. Though it feels like an extension of winter, the trend may actually be a product of the warming atmosphere. A warmer climate affects the jet stream, potentially pushing its course further south and leading to unusual weather patterns, such as unseasonable snowstorms in Colorado.

That means residents of some parts of the state will have to wait to have their summer hikes and picnics. The weather was serious enough to shut down one road in Rocky Mountain National Park.

[h/t CBS Denver]

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