National Weather Service United States Department of Commerce

On This Day In

                   Weather History

February 21st

Local and Regional Events:

February 21, 1918:

An amazing warm-up of 83 degrees in just 12 hours at Granville, North Dakota from Chinook winds. The temperature soared from an early morning low of 33 degrees below zero to an afternoon temperature of 50 degrees. Chinook winds are caused by the compression of Pacific air descending the Rockies. Compressing the air causes it to heat up resulting in the dramatic temperature rises.

The image above is the Cooperative Observers' Meteorological Record for Granville, North Dakota during the month of February 1918. The highest temperature for the month was 50 degrees, and the lowest was 33 below zero. Both occurred on the same day!

 

February 21, 1969:

Heavy snow along with winds of 15 to 25 mph caused blowing and drifting snow which closed many roads. Snowfall amounts of 5 to 12 inches were common across eastern South Dakota from the 20th into the 22nd. Some snowfall amounts included, 5 inches at Clear Lake and Brookings, 6 inches at Wilmot, 7 inches at Milbank, Redfield and Mitchell, 8 inches at Conde, 9 inches at Webster, Sioux Falls, and Huron.

 

Local Climate Information:

Click HERE for daily climate information for Aberdeen, Mobridge, Pierre, Sisseton, and Watertown.

Click HERE for daily climate information for Sioux Falls, Huron, Mitchell, and Sioux City.

 

U.S.A and Global Events for February 21th:

1971: A massive tornado outbreak occurred in the Delta region of northeastern Louisiana and Mississippi. The first major tornado touched down at about 2:50 p.m. in Louisiana and crossed into Mississippi. 46 were killed by this twister, which struck the towns of Dehli and Inverness. 121 people lost their lives that day, including 110 in Mississippi. A total of 1600 people were injured, 900 homes severely damaged or destroyed. The total loss was around 19 million dollars. 

The photos above are the courtesy of the Mississippi Delta Tornadoes of February 21, 1971, assessement report.

 

Click HERE for more This Day in Weather History from the Southeast Regional Climate Center.