Very warm and humid; thunder chances highest to the north

This is very warm weather, even for July.

Our average July 5 high is 83 degrees in the Twin Cities, but we’ll probably reach the lower 90s this Sunday afternoon. Dew points will be in the upper 60s to around 70 in most areas today, so it’ll feel muggy.

Due to the combination of heat and humidity, the National Weather Service has issued a heat advisory for the Twin Cities metro area from 10 a.m. to 8 p.m. this Sunday:

Here are details of the heat advisory:

URGENT - WEATHER MESSAGE National Weather Service Twin Cities/Chanhassen MN 259 AM CDT Sun Jul 5 2020 MNZ060>063-068>070-051800- /O.NEW.KMPX.HT.Y.0004.200705T1500Z-200706T0100Z/ Hennepin-Anoka-Ramsey-Washington-Carver-Scott-Dakota- Including the cities of Minneapolis, Blaine, St Paul, Stillwater, Chanhassen, Chaska, Victoria, Shakopee, and Hastings 259 AM CDT Sun Jul 5 2020 ...HEAT ADVISORY IN EFFECT FROM 10 AM THIS MORNING TO 8 PM CDT THIS EVENING... * WHAT...Heat index values to around 95 expected. * WHERE...Hennepin, Anoka, Ramsey, Washington, Carver, Scott and Dakota Counties. * WHEN...From 10 AM this morning to 8 PM CDT this evening. * IMPACTS...Hot temperatures and high humidity may cause heat illnesses to occur. * ADDITIONAL DETAILS...Relatively light winds and mostly sunny skies will combine with the high heat and humidity to create a heightened risk of heat illness, particularly for those who are active outdoors. PRECAUTIONARY/PREPAREDNESS ACTIONS... 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. 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 lightweight and loose fitting clothing when possible. 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.

Highs today will reach the lower 90s in central and southern Minnesota plus western Wisconsin, with some 80s in far northern Minnesota. It’ll be muggy, with dew points in the sticky 60s. A few spots may see a dew point of 70 degrees or higher.

Thunderstorm chances

Northern Minnesota has the best chance of thunderstorms this Sunday afternoon and evening, and their thunderstorm chances will continue into the overnight hours. There’s a chance of occasional scattered thunderstorms in central Minnesota and northwestern Wisconsin this afternoon into tonight. An isolated shower or thunderstorm is possible in the Twin Cities metro area, southern Minnesota and west-central Wisconsin later this afternoon and this evening, with a better chance of occasional showers and thunderstorms overnight.

You can hear updated weather information on the MPR network, and you’ll see updated weather info on the MPR News live weather blog.

The NWS Storm Prediction Center shows a slight risk (shaded yellow) of severe weather this afternoon/evening and overnight in parts of northwestern Minnesota:

Slight risk means that scattered severe thunderstorms are possible. There’s a marginal risk of severe weather this afternoon/evening and overnight in the dark-green shaded area that covers the remainder of northern Minnesota and much of central Minnesota, meaning that an isolated severe thunderstorm is possible. SPC will update the severe weather outlook several times today, and they may issue a severe weather watch for parts of Minnesota at some point.

The Grand Forks office of the National Weather Service has details on the potential weather hazards in northwestern Minnesota:

The week ahead

Unsettled weather will be with us this coming week, with scattered showers and thunderstorms possible each day. We’ll have many rain-free hours too.

Monday highs could top 90 degrees in the Twin Cities metro area and points to the south and east, with 80s elsewhere:

Monday dew points will be in the steamy 70s in southern Minnesota, with sticky 60s elsewhere:

Twin Cities metro area highs are projected to each the upper 80s Tuesday, followed by lower 90s Wednesday and around 90 on Thursday and Friday. We might reach the lower 90s on Saturday.

It looks like warm weather will be with us for a while. The NWS Climate Prediction Center shows a tendency for above-normal temps in Minnesota and Wisconsin from July 12 through July 18:

What is the record for hot days?

We hit 90 degrees at Minneapolis-St. Paul International airport Saturday afternoon. It was our 7th day this year with a high of 90 or warmer in the Twin Cities. Our long-term average is 11 days per year with a high of 90 or higher in the Twin Cities.

What’s the record for number days with a high of 90 or warmer? You better sit down for this one. Twin Cities weather records show that we had 44 days with highs of 90 or warmer in 1988. The Minnesota State Climatology Office compiled this list:

I remember that hot summer of 1988; my house didn’t have air-conditioning.

Programming note

You can hear my live weather updates on MPR News at 7:35 a.m., 9:35 a.m. and 4:35 p.m. each Saturday and Sunday.