22-12-2021, 10:55 AM
By JIM SALTER
December 21, 2021
O’FALLON, Mo. (AP) — A line of severe thunderstorms and tornadoes that swept across the north-central U.S. last week was the result of a serial derecho
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At least 45 tornadoes have been preliminarily confirmed in the Dec. 15 storms that crossed the Great Plains and Midwest
......
A derecho is often described as an inland hurricane. But, it has no eye and its winds come across in a line. The similarity is in the damage, which is likely to spread over a wide area, unlike a tornado where the damage is more spotty.
The weather service said a wind damage swath extending more than 240 miles (386 kilometers) with wind gusts of at least 58 mph (93 kilometers per hour) along most of its length can be classified as a derecho.
A derecho was also declared in August 2020 when storms packing 100 mph (161 kph) winds lasted several hours and caused damage from eastern Nebraska, across Iowa and into parts of Wisconsin and Illinois.
There was a difference: The August 2020 storm was a progressive derecho, while last week’s was a serial derecho.
......
a progressive derecho is fueled by a hot and moist environment with relatively strong winds aloft. Serial derechos are produced by storms with strong winds that bow outward
https://apnews.com/article/tornadoes-sto...cebd493bdf
December 21, 2021
O’FALLON, Mo. (AP) — A line of severe thunderstorms and tornadoes that swept across the north-central U.S. last week was the result of a serial derecho
......
At least 45 tornadoes have been preliminarily confirmed in the Dec. 15 storms that crossed the Great Plains and Midwest
......
A derecho is often described as an inland hurricane. But, it has no eye and its winds come across in a line. The similarity is in the damage, which is likely to spread over a wide area, unlike a tornado where the damage is more spotty.
The weather service said a wind damage swath extending more than 240 miles (386 kilometers) with wind gusts of at least 58 mph (93 kilometers per hour) along most of its length can be classified as a derecho.
A derecho was also declared in August 2020 when storms packing 100 mph (161 kph) winds lasted several hours and caused damage from eastern Nebraska, across Iowa and into parts of Wisconsin and Illinois.
There was a difference: The August 2020 storm was a progressive derecho, while last week’s was a serial derecho.
......
a progressive derecho is fueled by a hot and moist environment with relatively strong winds aloft. Serial derechos are produced by storms with strong winds that bow outward
https://apnews.com/article/tornadoes-sto...cebd493bdf