Excessive heat warning today through Friday

A dome of hot air is spreading over the Upper Midwest, and it will be with us until Friday evening.

Highs in the 90s and dew point temperatures in the 70s will lead to heat index values in the 100 to 116 degree range.

The Twin Cities office of the National Weather Service has issued an excessive heat warning from 1 p.m Wednesday through 7 p.m. Friday:

An excessive heat watch is in effect for western Wisconsin and far southeastern Minnesota.

A heat advisory extends from north of the Twin Cities to just north of Duluth, and into north-central and northwestern Minnesota:

The heat wave is affecting much of the United States, with 16 states posting either excessive heat warnings, heat advisories or excessive heat watches:

Steamy details

On average, we have 11 days per year in the Twin Cities with a high temperature of 90 degrees or warmer.

Last year we had only four days at or above 90 degrees in the Twin Cities. So far this year, we've tallied seven days with a high temp of 90 degrees or warmer.

We'll add to that total over the next three days!

Highs today:

Thursday will the hottest day this week:

Dew point temperatures in the 70s are expected this afternoon through Friday, which will generate heat index values of 100 to 116 degrees.

Coping with the heat

Here is a heat wave summary from the Twin Cities National Weather Service office:

Stay hydrated and as cool as possible over the next three days. Reduce time in the sun and avoid strenuous outdoor activities. It's a good idea to check on the well-being of people that you know who do not have air-conditioning.

Here are the symptoms of heat exhaustion and heat stroke:

On average, more people die annually of heat related illnesses in the U.S. than from any other weather phenomena.

Cooler this weekend

Highs in the 80s are expected to return this weekend. It'll also be less humid.

A few scattered thunderstorms are possible Friday night and Saturday.