textproduct: Twin Cities

KEY MESSAGES

- Extreme Heat Warning continues this evening, and Heat Advisory through Tuesday evening south & east. Heat index values approach 110F today, and 100F on Tuesday.

- Low chance of thunderstorms this evening, but, if thunderstorms are able to develop they could become severe with heavy rain.

- Hot & humid weather continues this week, although not nearly as intense as today. Continued low chances for thunderstorms as well.

DISCUSSION

Issued at 338 PM CDT Mon Jun 29 2026

It is hot. And it will stay that way for a while, though thankfully today will be the worst of the heat impacts this week. Dewpoints are generally in the mid to upper 70s for the entire region, though some pockets of 80F+ have started to pop up this afternoon. Air temperatures have been stifled a little more than expected by morning convection and afternoon cu field. Heat index values range from 100-110F this afternoon and evening, before getting some relief after sunset. This will be dependent on storm chances late this evening and overnight as a cold front looks to stall across central MN, dividing the state in half vertically. As cooler 700 mb temperatures advect in behind the front, that should provide enough forcing to overcome the cap and initiate at least scattered storms along the line. There is an explosive amount of instability (4500+ J/kg of MUCAPE), so any storms that are able to develop would likely become severe with damaging wind and heavy rainfall. The other thing to watch is a unsuspecting threat for tornadoes given the increasing amount of SRH values around sunset. There is a short 1-3 hour window of STP values jumping to 3+ just ahead of the front as the LLJ increases and surface winds decrease just enough to have a better hump to hodographs. The extent and strength of any potential tornado risk will depend on storm coverage and mode, which is uncertain right now given the widespread variance across hi-res models. There are some models, like the 18z RRFS, which have nothing develop this evening across our area. Because of this variance, PoPs are still limited, but the high end potential should still be messaged.

There is a growing signal for early morning convection to advect north from Nebraska and Iowa, especially if we end up seeing less storm coverage this evening. These storms would not have as conducive of an environment for severe development, but they would have an influence on our heat impacts for Tuesday. The more storms and lingering cloud cover, the less of an impact from heat. This is exactly what we saw today across parts of central and northern MN as a bow echo raced northeast. With this uncertainty in storm and cloud coverage, we opted to issue a Heat Advisory for a number of counties across south and eastern Minnesota as well as western Wisconsin. In areas that are not drastically impacted by storms, heat indices are expected to climb to about 100F Tuesday afternoon.

As the week progresses, not too much will change with the overall weather pattern. Upper level ridging will continue to dominate the eastern half of the CONUS, keeping the Upper MS Valley on the northwestern periphery of the heat dome. Our hot and muggy conditions will continue with highs anywhere between the mid 80s to low 90s and dewpoints generally in the upper 60s to low 70s. Heat risk will not be as much of a concern as it was today, though the persistent heat will continue to have an impact as it lingers for several days. A frontal boundary may stall out the region, which would provide several opportunities for additional storms through the rest of the week.

AVIATION /06Z TAFS THROUGH 12Z WEDNESDAY/

Issued at 1224 AM CDT Tue Jun 30 2026

Convection from earlier this evening has dissipated with VFR conditions at most terminals. SCT -TSRA is seen on radar for EAU with instances of MVFR conditions through 07z. Skies remain BKN to OVC at 5-10 kft with MVFR (BKN at 2-4 kft) for STC. Winds generally S to SSW at 8-13 knots with gusts to 20-25 knots over the next few hours, becoming 5-10 knots by 10z.

High resolution models continue to show a line of TSRA, or MCS- like feature moving NE out of Nebraska and Iowa before moving into Minnesota later this morning. PROB30s remain in TAFs for all terminals except AXN and STC. If this line of TSRA maintains and moves across the area flight categories may drop to IFR to MVFR. Something we will be monitoring over the next several hours and TAFs will be AMENDED if needed. High res models show this activity departing the area by 12-13z with BKN-OVC skies in it's wake. Skies will quickly clear by early afternoon with FEW at 5-10 kft and FEW to SCT at 20-25 kft this afternoon. Winds will be SW at 10-15 knots with gusts to 20-25 knots this afternoon.

KMSP...VFR conditions expected over the next several hours with BKN to OVC skies. Winds remain breezy out of the S/SSW at 10-15 knots with gusts to 20-25 knots. Winds will slowly decrease through the overnight and early morning timeframe. High res model guidance continue to show a line of TSRA or MCS-like feature moving NE out of Nebraska and Iowa before entering Minnesota later this morning. PROB30s for TSRA remain in the TAF. If said line of TSRA moves into the metro vicinity, flight categories may become IFR to MVFR by 10z. This is something we will continue monitoring in the coming hours and TAF will be AMENDED if needed. High res models show this activity departing the metro area by 12z with BKN to OVC skies in it's wake. Skies will quickly clear by afternoon with FEW at 5-10 kft and FEW-SCT at 20-25 kft during the afternoon. Winds in the afternoon will be SW at 10-15 knots sustained with gusts to 20-25 knots.

/OUTLOOK FOR KMSP/ WED...VFR. Chc -TSRA. Wind SW 8-13G20 kts. THU...VFR. Chc PM -TSRA. S 5-10 kts. FRI...VFR. Chc PM -TSRA. S 5-10 kts.

MPX WATCHES/WARNINGS/ADVISORIES

MN...Heat Advisory until 9 PM CDT this evening for Anoka-Blue Earth- Brown-Carver-Chisago-Dakota-Faribault-Freeborn-Goodhue- Hennepin-Le Sueur-Martin-McLeod-Nicollet-Ramsey-Rice- Scott-Sibley-Steele-Waseca-Washington-Watonwan-Wright. WI...Heat Advisory until 9 PM CDT this evening for Barron-Chippewa- Dunn-Eau Claire-Pepin-Pierce-Polk-Rusk-St. Croix.