textproduct: Twin Cities

KEY MESSAGES

- Showers and thunderstorms likely Tuesday. Low chances lingering into Wednesday, then chances increase this weekend.

- Cooler than average temperatures continue this week, then warmer and more humid this weekend into next week.

DISCUSSION

Issued at 331 PM CDT Mon Jun 22 2026

It's another Chamber of Commerce kind of weather day across the area, with highs comfortably in the 70s, still tolerable dewpoints, and light winds. Cloud cover has been building to the west though in response to the trough currently moving across Montana. It is this Montana trough that will bring us our next chance for showers and storms Tuesday as it moves along the Canadian border into the upper Great Lakes. A lead shortwave, combined with WAA will result in scattered showers/storms moving into western MN near sunrise Tuesday morning. We'll see a plume of lower 60s dewpoints build into southern MN ahead of a cold front, which will allow for mlCAPE values to build to around 1000 j/kg with peak heating Tuesday. This instability will be occurring beneath 30-40 kts of deep shear, so an at least marginally supportive environment for severe weather. HREF UH plots show some cyclonic and anti-cyclonic tracks across western MN Tuesday afternoon, though these come with fairly benign updraft strength thanks to the meager lapse rates. The Marginal Risk from the SPC still looks reasonable. A couple of feistier storms will be possible, with a marginal risk for hail, though we would also say a marginal wind threat exists, along with perhaps a very low tornado potential as the cooler temperatures will result in lower LCLs with those lower 60 dewpoints. Looking at QPF, HREF LPMM shows a few pockets of over an inch of rain being possible, but those amounts look spotty as opposed to widespread. In the end, this just looks like a rather typical summer convective event for the upper MS Valley.

For Wednesday, the upper low will be centered near western Lake Superior. This will put a zone of cyclonic flow with cooler temperatures aloft from central MN into western WI. As a result, fairly widespread, though disorganized diurnal activity is expected along and north of the I-94 corridor Wednesday afternoon. Thursday, the NBM came in dry, though you can't completely rule out some isolated showers in the same areas from Wednesday's threat, with some cyclonic flow lingering. However, Thursday looks like yet another Chamber of Commerce weather day, with highs in the low to mid 70s and dewpoints in the 50s. However, for the Chamber of Commerce, the days for their kind of weather looks numbered...

For Friday into early next week, we'll see a more significant pattern shift as an upper trough digs into the northern Rockies, with a ridge building into the Great Lakes. This will signal the return of warmer and more humid weather this weekend, along with an increasing risk for thunderstorms, thunderstorm complexes in particular. An at least small thunderstorm risk with WAA will start on Friday, but it's really late Saturday night into Tuesday that the EPS highlights for being rather active for the MPX area. In particular, Monday would be day to circle for a potential enhanced severe weather threat. Over half the EPS members show highs getting into the low 90s with dewpoints in the 70s and a cold front coming through. In addition, WxNext2 Machine Learning guidance from NCAR highlights the potential for trouble on Monday as well. We have a long ways to go, but the large scale features are at least pointing at Monday as being a day to pay close attention to as we work through the week.

AVIATION /18Z TAFS THROUGH 00Z WEDNESDAY/

Issued at 1223 PM CDT Mon Jun 22 2026

VFR through the period, with chances for showers & a few thunderstorms increasing across western Minnesota by the end of the period. BKN high-based cumulus this afternoon dissipate by sunset with ceilings lowering again through tomorrow morning. Winds will be generally northeasterly today with speeds around 5 kts or less & the become more southeasterly overnight. Winds become more southerly through the morning & speeds increase to around 10 kts, along with some gusts round 20 kts possible.

KMSP...Scattered showers & a few thunderstorms are expected tomorrow afternoon, mainly after 2 PM at MSP. Coverage will be spotty but at least a brief downpour looks possible, along with the chance for a rumble or thunder or two.

/OUTLOOK FOR KMSP/ WED...VFR, low chance PM -TSRA/MVFR. Wind NW 5-10kts. THU...VFR. Wind NW 5-10 kts. FRI...VFR. Chance PM -SHRA. Wind E 5-10 kts.

MPX WATCHES/WARNINGS/ADVISORIES

MN...None. WI...None.