Strong to severe storms likely later Monday in southern Minnesota

Updated 3:58 p.m.

We’re watching for storm initiation along a passing cold front Monday.

Afternoon temperatures have reached 90 degrees across parts of southern Minnesota. Temperatures are much cooler in the 70s in northern Minnesota behind the cold front.

Dew points have edged into the sticky 60s. That means there’s plenty of heat and enough moisture in the atmosphere for scattered storms later Monday. A cold front sliding southward through the Twin Cities late this afternoon will be the focus for storms.

Several short-range forecast models develop scattered storms along the front late Monday. The most likely scenario is for scattered storms to develop near or just south of the Twin Cities as the front passes through between about 4 p.m. and 8 p.m.

The National Oceanic and Atmospheric Administration’s Weather Research and Forecasting model shows a solution that’s typical for many forecast models for Monday: Storms develop near the Twin Cities, then slide south and east into the evening.

The loop below runs between 4 p.m. and 9 p.m. Monday evening.

NOAA’s Storm Prediction Center paints a slight risk for severe storms from the Twin Cities area to the south and east through this evening. Here’s the risk zone again:

Here’s the technical discussion from NOAA for our region.

Convergence along this boundary is expected to result in thunderstorm development during the late afternoon across southern MN and northern/central WI. Low 60s dewpoints are already in place in this area, with additional moisture advection helping to offset mixing throughout the day. As such, low 60s will likely still be in place later this afternoon, helping to support moderate buoyancy amid late afternoon temperatures in the upper 80s/low 90s. This region will also be on the southern edge of the stronger northwesterly flow aloft around the cyclone centered over northern Ontario. These environmental conditions should support robust updrafts along the front. Hail is possible with the initial development, but low-level lapse rates will likely support outflow-dominant storm structures, with upscale growth into one or more linear segment anticipated quickly. These convective lines are then expected to shift southward into more of central WI northern IA during the evening before dissipating amid nocturnal stabilization.

So keep an eye out for possible severe weather watches and warnings late Monday afternoon and evening.

The primary storm threats are large hail and damaging winds. Hopefully, some of us will get lucky and get under cells that produce significant downpours and much-needed rainfall in the drought zone.

A reminder we’ll carry severe weather warnings on KNOW 91.1 FM in the greater Twin Cities area and on MPR network stations around Minnesota as they occur.

Stay tuned.