After some very rough weather Monday, some Plains states will take another beating from severe thunderstorms today and tonight.
Severe storms struck from the Plains to the Northeast on Monday, July 6. The National Weather Service (NWS) received more than 320 reports of damaging winds and large hail in more than a dozen states, and a tornado touched down in northeastern Wyoming.
In South Dakota, quarter- to half dollar-size hail covered the ground in Winfred, around 60 miles from Sioux Falls, and hail the size of ping pong balls fell at the Interstate 90 exit for Alexandria.
Tennis ball to baseball size hail slammed parts of Crook County, Wyoming.
Wind gusts of 60 to 70 mph damaged structures, blew down trees and knocked out electricity in many communities.
The following features will make the atmosphere very unstable again across the Plains today, elevating thunderstorms to severe limits: A trough, which is an elongated area of low pressure; warm, humid air at the ground with much cooler air aloft; and twisting of the winds with altitude.
The NWS classifies a thunderstorm as severe if it produces any of the following based on radar or eyewitness reports:
• Winds of at least 58 mph (50 knots).
• Hail at least 1 inch in diameter (quarter size).
• A tornado.
Severe storms could pop up anywhere from Montana to the Dakotas, Minnesota, western Wisconsin, western Nebraska, eastern Wyoming and northeastern Colorado. Places at the highest risk are Glasgow and Billings, Montana; Williston and Dickinson, North Dakota; as well as Buffalo, South Dakota. The Storm Prediction Center (SPC), part of the NWS, has placed these areas under an “enhanced” risk, meaning numerous severe thunderstorms are possible in these cities and towns in between them.
Other potential targets include Great Falls, Montana; the rest of North Dakota; the northern half of South Dakota; in addition to the western half of Minnesota. These storms will affect drivers on portions of I-15, I-29, I-90 and I-94.
Besides wind, hail and tornadoes, torrential rainfall and flash flooding are possible.
Additional rounds of severe thunderstorms could hit the Plains again Wednesday, as well as the upper Midwest.
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