Transitioning to summer: heat, humidity and thunderstorms

Forecast graphic from National Weather Service in Duluth.

All was quiet on the weather front overnight, with chilly temperatures once again settling over the Arrowhead.  Ely and Hibbing checked in with 37 degrees at 5 a.m. A layer of clouds was moving across southwest Minnesota and early  morning temperatures were already in the 60s.

Heavy rains have left a large portion of the corn belt with wet fields in the last week.  This regional rainfall graphic from the Midwest Climate Center paints a picture of the drenched landscape:

Accumulated seven day rainfall (Source:Midwest Regional Climate Center)

High temperatures today will top out in the 60s along the shoreline of Lake Superior with readings in the lower 80s in western Minnesota this afternoon.

Highs forecast for today

The early morning visible satellite image shows clouds over parts of northern Minnesota as well:

Clouds depicted on 615 a.m. CDT Visible Satellite image

Mid summer-like weather arrives on Thursday and is likely to hang around several days.  Forecasters will be challenged to pin-point timing and location of heavy to strong thunderstorms.

Heat and humidity will build on Thursday and severe thunderstorms are possible, particularly in the afternoon and evening.

NAM prediction of lifted index(unstable air) indicated by red lines. Dew points in shaded colors. (Source:NOAA/College of DuPage)

You can see the lifted index is minus seven in southwest Minnesota with dew points around 70.  This combination is likely to lead to showers and thunderstorms.

NAM predicts a cluster of thunderstorms Thursday afternoon focused in southwest Minnesota. (Source:NOAA/College of DuPage)

The probability of storms producing damaging winds and hail is shown in this graphic from NOAA’s Storm Prediction Center:

Storm Predictions severe weather outlook for Thursday.


Temperatures will approach 90 F in a large part of southern Minnesota on Friday. (Source:NOAA/College of DuPage-NAM)

Very warm and humidity conditions and more thunderstorms can be expected for Saturday.

Afternoon temperatures forecast by the GFS for Saturdy. (Source:NOAA/

Surface temperatures forecast by the GFS for 1 p.m. CDT Saturdy. (Source:NOAA/

Today may be the best day to attend to oudtoor chores.  I’m going to try and getting some painting done, which has been planned since Memorial Day weekend.

  • Tina Hegg Teeter

    So how does Duluth’s weather look for Grandma’s Marathon on Saturday?