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 /06Z TAFS THROUGH 12Z FRIDAY/

Issued at 1231 AM CDT Thu Jul 2 2026

VFR conditions expected through most of the period. Skies will continue to clear in the next few hours with SKC to FEW250 during the remainder of the overnight. Some of the high res guidance show areas of fog developing across central/western MN and western WI this morning, confidence is greatest for western WI terminals. Therefore, TEMPO for fog has been added to RNH and EAU from 09-12z with VIS reductions of 3 miles or lower. If VIS drops to IFR or LIFR flight categories for RNH and EAU, TAF AMENDs will be needed, but for now expect areas of fog to develop across portions of western WI. Winds light at AOB 5 knots and VRB or southerly through the morning hours. By late morning and afternoon winds will become 5-10 knots. Guidance is also showing another round of showers and storms this evening/overnight timeframe. That said, HREF ensemble reflectivity > 40dbz paintball output shows a not so confident depiction of evening storms, therefore forecast confidence is low. Hence no mention in this TAF issuance. Updates will be likely at future TAF issuances when high res guidance depicts activity a little better.

KMSP...VFR conditions expected through the overnight/morning hours and through most of the day. Winds light AOB 5 knots and VRB or southerly in direction, winds will become 5-10 knots by late morning and afternoon timeframe. Skies will be SKC to FEW250 through the overnight with FEW-SCT250 during the late morning and afternoon. FEW at 5-10 kft will be possible during the afternoon hours as well. Guidance continues to show another round of evening and overnight showers and storms. However, confidence is low at this time, so no mention in this TAF issuance.

/OUTLOOK FOR KMSP/ FRI...Chc MVFR/TSRA. Winds S 5-10 knots, becoming E. SAT...Chc MVFR/TSRA. Winds NE 5-10 knots. SUN...Chc AM SHRA/TSRA. PM VFR. Winds E 5-10 knots

MPX WATCHES/WARNINGS/ADVISORIES

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