A strong late spring cold front could trigger a line of potent thunderstorms tonight in several Upper Midwestern states.
The storms will stretch from northern Nebraska to central and northwestern portions of Minnesota, potentially impacting truckers on sections of Interstates 29, 90 and 94 from late evening into the wee hours of Thursday.
Prior to the evening arrival of the cold front, a combination of warm temperatures and high humidity at the surface, along with sharp lapse rates – quickly falling temperatures from the surface into the mid-atmosphere – will make the air unstable, leading to thunderstorm development.
Some storms could become severe, producing scattered areas of intense straight-line winds and large hail, in addition to an isolated tornado. The National Weather Service (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
• A tornado
Some areas could also be hit with localized flash flooding.
Some of the places in the risk zone of tonight’s severe weather include Valentine, Nebraska; Aberdeen and Watertown, South Dakota; Fargo and Grand Forks, North Dakota; as well as Thief River Falls, Minnesota.
The good news is the severe storm threat will be short-lived, with only scattered “garden variety” storms lingering for a while after sunrise Thursday.
Severe storms may hit parts of the Bismarck, Rapid City and St. Cloud freight markets, where Outbound Tender Volume Index weekly changes (OTVIW), according to FreightWaves SONAR, have increased. So drivers may be headed to these places to pick up loads. However, outbound volumes have decreased a bit or only marginally increased in other markets that may get hit by severe storms tonight, like Fargo and Sioux Falls.
Thunderstorms could pop up Thursday afternoon or evening from Texas to the Great Lakes. A few of these storms could reach severe limits.
A separate system Wednesday could spark a few isolated severe thunderstorms from eastern North Carolina to southern Virginia. The risk is low, but not zero. There’s also potential for localized flash flooding.
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