Excessive heat warning Friday; thunderstorms Saturday

It'll be another steamy day for most of Minnesota.

The hottest temperatures this afternoon will be over central and southern Minnesota:

Hot temps, combined with dew point temperatures in the upper 60s to mid 70s, will lead to heat index values in the 100 to 110 degree range this afternoon in many spots.

An excessive heat warning is in effect until 7 p.m. for much of southern Minnesota, including the Twin Cities:

Here is a nice summary of our weather today through Saturday:

More information on all aspects of heat wave safety can be found here.

Saturday thunderstorms

A low-pressure system and trailing cold front will move toward us Saturday afternoon, igniting some thunderstorms.

Here is the Saturday afternoon and evening thunderstorm activity, as depicted by the National Oceanic and Atmospheric Administration’s North American Mesoscale Forecast System:

The Storm Prediction Center of the National Weather Service indicates a slight risk of severe weather over much of Minnesota and western Wisconsin Saturday and Saturday night:

The highest risk of severe weather in the Twin Cities would tend to be from about mid afternoon into the evening on Saturday, but check back for later forecast updates.

Weekend temps

Highs Saturday will be around 90 in the south, 80s elsewhere:

Some upper 70s are possible along the north shore of Lake Superior.

If the low-pressure system moves more slowly, you can expect a delay in the thunderstorm activity, and highs in the 90s over southern Minnesota.

Highs on Sunday will be cooler:

It'll also be less humid on Sunday.

Programming note:

You can hear my live weather updates at 7:35 a.m. and 4:35 p.m. each Saturday and Sunday on Minnesota Public Radio.