textproduct: Twin Cities

KEY MESSAGES

- Hot & humid today into saturday with heat index values of 95-100 possible. Heat Advisory in effect for Twin Cities metro during the afternoon.

- Frequent chances for scattered showers & thunderstorms into next week.

DISCUSSION

Issued at 352 AM CDT Fri Sep 4 2026

Heat and humidity are the main weather concern for today, with widespread heat indices in the 90s expected this afternoon. A pool of dewpoints in the low 70s remain across much of the southern half of MN and western WI, however northerly winds and outflow from last night's storms will usher in lower dewpoints. This will limit heat indices from getting too out of control, though southern MN may hold onto enough of this moisture into the afternoon to approach 100 degree heat indices. The urban heat island of the Twin Cities metro will be the most vulnerable to heat impacts, with afternoon heat indices hovering right around that lower threshold of 95F. At the same time, WBGT are forecasted to be around 84-85F in the metro as well, even with our lower sun angle this time of year. This reaches a threshold for high risk of heat related illness and suggests limited exercise outside, especially for vulnerable populations. We have opted to go ahead with a metro- specific Heat Advisory despite the uncertainty and borderline values. It will be hot today regardless of thresholds and given that it is early September, it felt worthwhile to give the extra messaging boost for this anomalous heat. Our most recent Heat Advisory for the metro dates back to July 27th.

The best chance for any storms today will be along the MN/IA border, though the latest hi-res guidance continues to trend dry for the region.

We remain in a hot and stormy pattern with ridging in place overhead through early next week. Long range guidance continues to favor storms and appreciable rainfall over western MN and the Dakotas where better forcing from northeastward advancing shortwave disturbances is expected. The SWODY2 and 3 both depict this idea as well, with the marginal risks each day only clipping a part of western MN. The best chance for widespread precip will likely come some time Monday into Tuesday as a more organized shortwave breaks down the upper level ridge. Winds will then increase out of the northwest and advect in more seasonable temperatures and drier air through the end of the week.

AVIATION /18Z TAFS THROUGH 00Z SUNDAY/

Issued at 1152 AM CDT Fri Sep 4 2026

The stubborn stratus deck continues to slowly erode as we head into the afternoon, with satellite showing the thinning such that we should finally see it become mostly sunny by around 20z for most locations. All sites should lift to VFR until at least 03-04z, at which point more low clouds/fog become possible. One difference between this morning and the upcoming period is that winds are generally stronger, except for RNH/EAU, such that fog should be a bit patchier although periods of IFR remain possible. Drier air is also advecting in from winds that will favor northerly, so we should not see a repeat of today in that most of the low clouds/fog should dissipate by roughly 15-16z.

KMSP...Kept some of the stratus around until 20z but remaining VFR, with a chance for IFR arriving as early as 08-09z with more low stratus/fog. Not as confident as this morning's round, but still enough to maintain the TEMPO inherited from the 12z TAF. We become VFR through the rest of the period after around 16z tomorrow.

/OUTLOOK FOR KMSP/ SUN...Chc SHRA/TSRA/MVFR. Wind SE 5-10kts. MON...Likely SHRA, chc TSRA/MVFR. Wind SE 10-15kts. TUE...Likely SHRA, chc TSRA/MVFR. Wind S 10-15kts.

MPX WATCHES/WARNINGS/ADVISORIES

MN...Heat Advisory until 6 PM CDT this evening for Anoka-Carver- Dakota-Hennepin-Ramsey-Scott-Washington. WI...None.