Thursday, January 21st 2021, 10:35 am - Between January 21–23, 1999, 127 tornadoes touched down across the Mississippi River Valley.
Between January 21–23, 1999, 127 tornadoes touched down across the Mississippi River Valley. The outbreak caused extreme damage and killed nine people. The best-known tornado is the one that occurred in Little Rock, Arkansas, which killed three people.
The storms that caused the tornadoes also came with damaging winds and baseball and grapefruit-size hail.
The red dots are tornadoes, the blue dots are damaging winds, and the green dots are large hail. Courtesy of NOAA
The conditions were so favourable for tornadoes because a broad upper-level trough, with its axis positioned across the Central United States, quickly intensified upon interacting with a 280 km/h jet streak from the southern Rockies.
At the surface, there was a low-pressure system near the Texas–Oklahoma border, and early on Jan. 21, it deepened and accelerated eastward into Arkansas.
On Jan. 21, the Storm Prediction Center (SPC) issued high-risk weather warnings across Arkansas, Tennessee, Louisiana, and Mississippi. That day, Arkansas experienced the largest tornado outbreak in its history, with a total of 56 cyclones.
A home on Main Street in White County after it was hit by a tornado on Jan. 21, 1999. Courtesy of NOAA
Arkansas usually sees 33 tornadoes in a year, and usually, they occur during the spring. The next day, there were an additional 51 tornadoes, for a total of 107 in two days.
A high school gym that was destroyed by a tornado in White County Jan. 21, 1999, A girl's high school basketball game was played that evening even though the school's officials were aware of the severe weather warnings. The game was stopped early and no one was hurt. Courtesy of NOAA
Little Rock, Arkansas was hit by two strong tornadoes on the same day. The first one, which started at 6:33 pm, lasted 29 minutes and travelled 35 km, crushing hundreds of buildings in its path. The second tornado developed as the first one dissipated and lasted until 7:02 pm.
To hear more about the four-day 1999 tornado outbreak, listen to today's episode of "This Day In Weather History."
This Day In Weather History is a daily podcast by The Weather Network that features unique and informative stories from host Chris Mei.
Thumbnail: Damage from the Jan. 1999 Little Rock Tornado. Courtesy of Wikipedia