Steamy afternoon; excessive heat warning, with a thunderstorm chance

Much of the southern half of Minnesota will have highs in the 90s and dew point temps in the lower 70s this Friday afternoon.

The hot and humid weather has prompted an excessive heat warning for the Twin Cities metro area from 1 p.m. to 7 p.m., and heat advisories elsewhere:

Here are details of the excessive heat warning:

URGENT - WEATHER MESSAGE

National Weather Service Twin Cities/Chanhassen MN

1118 AM CDT Fri Jun 15 2018

MNZ060>063-068>070-160000-

/O.UPG.KMPX.HT.Y.0004.180615T1800Z-180616T0000Z/

/O.NEW.KMPX.EH.W.0002.180615T1800Z-180616T0000Z/

Hennepin-Anoka-Ramsey-Washington-Carver-Scott-Dakota-

Including the cities of Minneapolis, Blaine, St Paul, Stillwater,

Chaska, Shakopee, and Hastings

1118 AM CDT Fri Jun 15 2018

...EXCESSIVE HEAT WARNING IN EFFECT UNTIL 7 PM CDT THIS EVENING...

The National Weather Service in Twin Cities/Chanhassen has issued

an Excessive Heat Warning, which is in effect until 7 PM CDT this

evening. The Heat Advisory is no longer in effect.

* TEMPERATURE...High temperatures in the mid 90s will combine with

high humidity to yield peak heat indices in the 98 to 103 range

this afternoon.

* IMPACTS...Heat illnesses are possible for those active outdoors

or those susceptible to heat illnesses, such as children and

the elderly.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Take extra precautions...if you work or spend time outside. When

possible...reschedule strenuous activities to early morning or

evening. Know the signs and symptoms of heat exhaustion and heat

stroke. Wear light weight and loose fitting clothing when

possible and drink plenty of water.

To reduce risk during outdoor work...the occupational safety and

health administration recommends scheduling frequent rest breaks

in shaded or air conditioned environments. Anyone overcome by heat

should be moved to a cool and shaded location. Heat stroke is an

emergency...call 9 1 1.

An Excessive Heat Warning means that a prolonged period of

dangerously hot temperatures will occur. The combination of hot

temperatures and high humidity will combine to create a dangerous

situation in which heat illnesses are likely. Drink plenty of

fluids...stay in an air-conditioned room...stay out of the sun...

and check up on relatives and neighbors.

Young children and pets should never be left unattended in vehicles

under any circumstances. This is especially true during warm or

hot weather when car interiors can reach lethal temperatures in a

matter of minutes.

And details of the heat advisory:

URGENT - WEATHER MESSAGE

National Weather Service Twin Cities/Chanhassen MN

1118 AM CDT Fri Jun 15 2018

MNZ051-059-066-067-074>078-082>085-091>093-WIZ023-024-160000-

/O.NEW.KMPX.HT.Y.0005.180615T1800Z-180616T0000Z/

Sherburne-Wright-McLeod-Sibley-Brown-Nicollet-Le Sueur-Rice-

Goodhue-Watonwan-Blue Earth-Waseca-Steele-Martin-Faribault-

Freeborn-St. Croix-Pierce-

Including the cities of Elk River, Monticello, Hutchinson,

Gaylord, New Ulm, St Peter, Le Sueur, Faribault, Red Wing,

St James, Mankato, Waseca, Owatonna, Fairmont, Blue Earth,

Albert Lea, Hudson, River Falls, and Prescott

1118 AM CDT Fri Jun 15 2018

...HEAT ADVISORY IN EFFECT UNTIL 7 PM CDT THIS EVENING...

The National Weather Service in Twin Cities/Chanhassen has issued

a Heat Advisory, which is in effect until 7 PM CDT this evening.

* TEMPERATURE...High temperatures in the mid 90s will combine with

high humidity to yield peak heat indices in the 98 to 103 range

this afternoon.

* IMPACTS...Heat illnesses are possible for those active outdoors

or those susceptible to heat illnesses, such as children and the

elderly.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Heat Advisory means that a period of hot temperatures is

expected. The combination of hot temperatures and high humidity

will combine to create a situation in which heat illnesses are

possible. Drink plenty of fluids...stay in an air-conditioned

room...stay out of the sun...and check up on relatives and

neighbors.

Take extra precautions...if you work or spend time outside. When

possible...reschedule strenuous activities to early morning or

evening. Know the signs and symptoms of heat exhaustion and heat

stroke. Wear light weight and loose fitting clothing when possible

and drink plenty of water.

To reduce risk during outdoor work...the occupational safety and

health administration recommends scheduling frequent rest breaks

in shaded or air conditioned environments. Anyone overcome by heat

should be moved to a cool and shaded location. Heat stroke is an

emergency...call 9 1 1.

Heat safety tips

Heat exhaustion and heat stroke have these symptoms:

Thunderstorms at times

Scattered thunderstorms are possible in Minnesota and western Wisconsin Friday afternoon and evening.

Many areas will also see a round of thunderstorms overnight into early Saturday, followed by redevelopment Saturday afternoon and evening and a possible wave of thunderstorms Saturday night.

Additional waves of showers and thunderstorms are expected on Sunday. Areas that receive the most thunderstorm activity could see some flooding.

Parts of northeastern Minnesota, including Duluth, and northwestern Wisconsin are in a flash flood watch through Sunday morning. A flash flood watch means that conditions may develop that lead to flash flooding.

There will be some dry periods this weekend, but have a plan B for outdoor activities; you may have to duck for cover at times.

Severe weather outlook

The Storm Prediction Center of the National Weather Service shows the Twin Cities metro area and points to the northeast, plus west-central Wisconsin, in a slight risk of severe weather Friday afternoon and night:

Much of the remainder of Minnesota is in a marginal risk of severe weather.

Slight risk means that scattered severe thunderstorms are possible:

A good chunk of Minnesota, including the Twin Cities metro area, is included in the SPC slight risk of severe weather Saturday through Saturday night:

The Sunday slight risk area also includes the Twin Cities:

Updated weather information can be heard on the Minnesota Public Radio Network, and updates are also posted on the MPR News live weather blog.

This will be a good weekend to have your NOAA weather radio or mobile phone nearby for weather warnings.

Travelers will want to be aware of which county they are in, because weather warning headlines typically list the county or counties being warned.

Weekend temps

Saturday highs will be warmest to the south and coolest to the north:

Sunday highs will also be warmest to the south:

Twin Cities metro area highs return to the upper 70s for Monday and Tuesday, followed by lower 80s on Wednesday and Thursday.

Programming note

You can hear my live weather updates on Minnesota Public Radio at 7:49 a.m. Thursdays and Fridays, and at 7:35 a.m., 9:35 a.m. and 4:35 p.m. each Saturday and Sunday.