AccuWeather Global Weather Center – The threat for severe weather is set to continue across the High Plains and Upper Midwest through midweek across many areas that have already had to deal with daily severe thunderstorm activity.
Across the Dakotas, reports of damaging wind gusts or large hail have been reported from July 2-6, and the severe threat that is expected on Tuesday will likely continue that streak to six days in a row of severe activity. Although storms are expected to be severe across these states, the greatest threat for very large hail, strong wind gusts and even an isolated tornado or two will likely come farther west across the Big Sky Country in Montana.
Tuesday's threat for severe weather will be driven by a storm system originating in the upper levels of the atmosphere that will be tracking into the Northwest during the day. This system will quickly track eastward, tapping into a very hot and unstable atmosphere once it tracks into Montana.
Into the nighttime hours, the atmosphere is expected to remain unstable enough to support potentially damaging thunderstorms into the Dakotas as the storm system treks eastward. It is possible that by this time, thunderstorms could congeal into a large line or complex, known as a mesoscale convective complex (MCC) or mesoscale convective system (MCS).
As the storms do so, the primary threat will transition to damaging straight-line winds. For those that may be traveling along the Interstate-94 corridor, thunderstorm activity will need to be closely monitored. The threat area would also include almost anyone across the state of North Dakota, northern South Dakota and possibly extending as far east as northwestern Minnesota.
In the wake of Tuesday's thunderstorm activity, the same storm system responsible for the thunderstorm activity is expected to spark potentially dangerous thunderstorms once again on Wednesday.
The threat on Wednesday will shift eastward into the Midwest and central Plains, bringing an end to the threat across Montana and most of the Dakotas.
Residents in the Twin Cites of Minnesota, Sioux Falls, South Dakota, and Omaha, Nebraska, will be under the gun for severe weather late Wednesday afternoon and overnight.