textproduct: Twin Cities

KEY MESSAGES

- TODAY, Severe thunderstorms possible this afternoon and evening, mainly across southern Minnesota and west central Wisconsin. Hail, wind, and a few tornadoes are possible, along with heavy rain and localized flooding.

- HOLIDAY WEEKEND, additional thunderstorm chances continue throughout the Holiday Weekend. There is a risk for severe weather and heavy rain with these storms, but timing and location are uncertain.

- Warm & muggy conditions continue but dangerous heat indices are unlikely.

DISCUSSION

Issued at 158 PM CDT Wed Jul 1 2026

TODAY AND TONIGHT...The main concern is for storms with severe weather and heavy rain. Early afternoon satellite imagery showed a few high clouds along the IA/WI border, and radar showed some precipitation returns along with a few lightning strikes. This area had received morning convection, and that is important since additional storms are expected there later today.

From the severe weather aspect, LCLs are very low, and the surface winds have an easterly direction. This is leading to Effective Helicity values near 200 m2/s2, both of which support a tornado potential later this afternoon and evening along I-90 and into west central Wisconsin. As we go forward in time, the surface winds are expected to veer with time and become more southwest. This would reduce the tornadic threat, which can be visualized in the Effective SRH values decreasing to around 100 m2/s2 by 00Z this evening. So the surface winds will be a key in determining the tornado threat later today.

Aside from tornadoes, there will be ample CAPE and deep layer shear to support organized convection. However the mid level lapse rates are only around 7 C/km, so not anticipating extremely large hail, or a significant cold pool to produce high-end damaging winds. Instead expect a few severe storms with typical large hail and damaging winds.

The moist mid-level lapse rates are indicative of the high precipitable water, with values near 2 inches in place. Any storms that form will be capable of produce heavy rain and flooding. Areas that are most at risk are along I-90, where they already had storms this morning, and could see training storms later today as well. These storms will eventually exit the region late this evening, setting up a mostly dry day for Thursday.

THURSDAY THROUGH TUESDAY...Additional round of storms expected through the weekend and into next week. The pattern remains fairly steady, meaning any storms that develop could produce severe weather and heavy rain.

Mostly dry conditions are expected on Thursday, but late Thursday night into Friday morning is a time frame to watch for thunderstorms. We expect a complex of storms to develop in the Dakotas Thursday night, and either move into Minnesota and Wisconsin on Friday morning, or dive south into Iowa. This storm will have sufficient CAPE and shear to produce severe weather. The main threat is damaging wind, with a secondary threat tornadoes and hail.

Looking ahead, there is no strong signal for storms the rest of the weekend, but the guidance suggests that storms will be possible. As mentioned earlier, severe weather and heavy rain will accompany these thunderstorm complexes. As we transition to next week, the heavy rain and flooding threat increases. The EC and GFS Ensembles both have multiple members with 4 to 5 inches of rain between now and next week. This indicates that multiple rounds of storms will lead to higher rainfall totals somewhere across the forecast area. And each round will saturate soils, resulting in higher runoff potential with the next round. So the flooding threat bears watching over the next few days.

AVIATION /18Z TAFS THROUGH 00Z FRIDAY/

Issued at 1256 PM CDT Wed Jul 1 2026

Except for an isolated pocket of MVFR ceilings which may move across a terminal briefly early this afternoon, VFR conditions will prevail at all sites into late this afternoon. Scattered TSRA still look to develop late this afternoon into the early evening hours, which may produce MVFR conditions mainly for southern-eastern MN into western WI. Best chances are MKT- MSP-EAU, so have run with TEMPO groups at those sites, with lesser chances at RWF-RNH so have used PROB30 mention at those sites. Lower clouds scour out overnight with high ceilings expected to remain in place overnight through most of Thursday. Chances for additional rounds of for SHRA/TSRA increase for Thursday night, but that is beyond the timeframe of this TAF set so the next few routine TAFs will have mention of precip for Thursday night. Breezy S to SW winds will continue through this afternoon, with winds then going light/variable overnight through the first half of Thursday.

KMSP...Not much change from the inherited 01/12z TAF set. Did up the precip mention from a PROB30 to a TEMPO for the 22z-01z timeframe late this afternoon. Still some uncertainty in the placement of storms, but even within the 5mi radius around the terminal, chances are fairly high that scattered TSRA later today may impact MSP either directly over the terminal or flight paths. Gusty winds will continue through the afternoon hours, and TSRA could produce sharp wind shifts along with additional gusty winds. Conditions improve this evening as winds settle down and lower clouds scour out. Next chance for precipitation doesn't arrive until Thursday night so tranquil conditions are expected for the overnight hours through most of Thursday.

/OUTLOOK FOR KMSP/ FRI...SHRA likely, chc MVFR/TSRA. Winds S 5-10kts becoming E. SAT...SHRA likely, chc MVFR/TSRA. Winds SE 5-10kts becoming NE. SUN...VFR. Wind E 5 kts.

MPX WATCHES/WARNINGS/ADVISORIES

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