National Weather Service confirms Dec. 15 derecho, first ever reported in December
Published: Dec. 20, 2021 at 7:20 AM CST
CEDAR RAPIDS, Iowa (KCRG) - The National Weather Service has confirmed the Dec. 15 derecho event was a “serial derecho.”
It’s also been confirmed to be the first December derecho reported on record in the U.S. since severe weather records began.
The total number of tornadoes that occurred in Iowa also stands at 21
The National Weather Service said there were a total of 21 tornadoes in Iowa on Dec. 15, but that number may be revised as additional surveys take place.
To officially be categorized as a derecho, winds must be 58 m.p.h. or greater, extending for 240 miles or more.
For an explanation on how Dec. 15′s serial derecho differs from the Aug. 2020 progressive derecho, click here.
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