textproduct: Twin Cities

KEY MESSAGES

- Severe thunderstorms likely tonight. Damaging wind is the primary threat, especially across western and central Minnesota.

- Another round of severe thunderstorms Wednesday afternoon. All severe modes are possible including damaging wind, large hail, and tornadoes. Greatest severe threat favors eastern Minnesota/western Wisconsin Wed afternoon into Wed evening.

- Slightly cooler than normal temperatures forecast for Thursday through the weekend.

DISCUSSION

Issued at 1244 AM CDT Wed Jun 10 2026

The next 24 hours will feature the potential for multiple rounds of severe thunderstorms across the Upper Midwest. Current regional radar mosaic highlights a line of thunderstorms stretching from Winnipeg south through the Dakotas and into northern Nebraska. A decaying MCS moving northeast out of Nebraska has begun to merge with the easterly moving convection over SoDak. These storms will then track ENE into SW/W MN shortly by 1 AM and continue through the MPX forecast area tonight. A Severe Thunderstorm Watch is in effect across portions of western MN until 4 AM. Locations further east may need an additional watch, but that will be determined at a later time.

Tonight's severe threat comes in the form of a squall line that is driven by a potent 50+ knot low level jet. The squall line will have a reservoir of abundant instability to tap into with guidance suggesting 2000+ J/Kg MLCAPE present over W & C MN. A quick mesoanalysis highlights 1500 J/Kg DCAPE over W MN, 35-40 kts of effective wind shear, and steep mid-level lapse rates. While the environment will gradually wane, the dynamics associated with the LLJ should support a severe threat through much of tonight. Damaging wind gusts looks to be the main severe weather hazard with the line of storms, but a few quick QLCS tornadoes can't be ruled out within the line. The apex of the squall line should track from W MN through E MN and into W WI by daybreak. How much severe threat will the line have when it makes it into the Twin Cities and western Wisconsin is difficult to say, but there should be some severe potential despite the early morning time frame.

This line has a history of producing severe wind gusts of 75+ MPH over SoDak earlier tonight and is moving into a more favorable low level kinematic environment that short lived QLCS tornadoes will be possible, especially over W MN. My immediate concern is that the merger between the north-northeast moving decaying MCS/MCV and the easterly moving squall will merge and enhance the wind threat... at least initially across far E SD and W MN.

On Wednesday, we'll dry out by mid-morning in the wake of the MCS. How much convective debris is left over to limit the atmospheric recovery will ultimately impact Wednesday afternoon's severe weather potential. Guidance does limit how much additional convection fires up through the morning hours, allowing 2000 to 3000+ J/Kg MLCAPE to pool ahead of the approaching cold front. This will support a higher end severe weather environment with 40+ kts of bulk shear, sufficient lapse rates, and favorable wind profile aloft. There are a few questions that remain less certain. When and where will the initial storms develop in the afternoon? Current thoughts are for convection to fire early afternoon along I-35 before moving into W WI. Initial storms will be supercells capable of all severe modes including large to very large hail, damaging winds, and tornadoes are all possible. A favorable environment for tornadoes will be in place across W WI that will have the potential for a few strong Tornadoes. Initial supercells will quickly grow upscale into a linear complex that'll primarily pose a damaging wind threat across W WI. Severe threat wraps up late Wednesday evening and we'll look to dry out & cool down overnight.

Another chance of precipitation arrive behind the cold front Thursday afternoon. Severe threat will be low, but an additional round of rain is likely. A much cooler & drier airmass will settle in Friday and stick around for the weekend. The mid level ridge will shift from the Upper Midwest downstream to the eastern CONUS. This will place zonal westerly flow over the northern Plains and Upper Midwest. Temperatures will run 5 to 10 degrees below normal (that's high temperatures in near 70) with lows in the 40s and 50s... a welcome break for the AC units across MN and W WI. A few additional chances of rain will exist, primarily on Saturday, but over a much drier pattern will persist into next week.

AVIATION /06Z TAFS THROUGH 12Z THURSDAY/

Issued at 1244 AM CDT Wed Jun 10 2026

VFR to start for all sites but lower clouds/precip will develop fairly quickly early in this TAF duration as confidence remains fairly high that an MCS will traverse MN-WI overnight, generally in the 06z-10z timeframe from western TAF sites to eastern TAF sites. Conditions will likely drop to IFR, mainly due to heavy rain with the thunderstorms associated with the overnight system. In addition strong/gusty winds with a sharp directional change is possible as the system moves across any given terminal. Have kept the TS mention to just the TEMPO so as to not thrust a 3-4hr solid TS window at any given site. Conditions will temper down just prior to daybreak, with VFR conditions likely for much of the day today. Another round of thunderstorms looks to develop in far eastern MN late this afternoon then progress eastward across WI this evening. The Wednesday system looks to be stronger than the one for tonight, but the Wednesday system looks to more heavily impact the WI sites, possibly as far west as MSP.

KMSP...First round of storms looks to move across MSP in the 08z-10z timeframe per decent multi-CAM agreement. Ceilings likely down to MVFR while visibilities drop to IFR-or-lower, dependent on rainfall intensity. Gusty winds and frequent lightning are likely to come with the thunderstorms. These overnight storms are expected to conclude prior to the Wednesday morning push, resulting in VFR conditions through mid- Wednesday afternoon. Another round of storms looks to develop over eastern MN late Wednesday afternoon and slide east. Still some uncertainty as to whether MSP will be impacted, thus have maintained the PROB30. Even if the storms do not directly impact MSP, routes eastward of MSP will be impacted.

/OUTLOOK FOR KMSP/ THU...VFR. -RA likely. Slight chc PM -TSRA. Wind SW 5-10kts becoming W 10-15G25kts. FRI...VFR. Wind W 15G30kts. SAT...VFR. Wind NW 5-10kts.

MPX WATCHES/WARNINGS/ADVISORIES

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