textproduct: Twin Cities

KEY MESSAGES

- Another prolonged heat wave begins this weekend. An Extreme Heat Watch is in effect Saturday through Sunday across southern Minnesota, including the metro.

- Occasional low chances for showers and storms exist through most of next week. The best chance is Sunday night.

DISCUSSION

Issued at 321 AM CDT Fri Jul 24 2026

Scattered showers have been blossoming across western Minnesota since yesterday evening. A moisture gradient and a modest LLJ seem to be the main culprits. These showers may expand eastward more during the next several hours before weakening by mid morning. PoPs may need to be increased and expanded east if current radar trends continue. A stronger mid level disturbance is passing across northern IA, which has allowed more widespread and steadier showers south of the border. That wave is sliding east southeast and those showers will remain to the south. Later in the day and tonight, a short wave will pass through ND and northern MN. Storms may fire late this afternoon across eastern ND and propagate east this evening. Steeper lapse rates will spread east to the Upper Midwest and a modest LLJ may allow the storms to continue into parts of central MN by late evening before weakening.

A large and intense ridge will remain centered over the Four Corners to southern high Plains region through at least next week. This lends lower confidence to the forecast locally compared to when it was centered overhead last week for several reasons:

1.) Several weak disturbances will traverse the periphery of the ridge which may spark chances for thunderstorms at any time. Such disturbances are very difficult to predict more than a couple days in advance.

2.) Elevated wildfire smoke in the west northwest flow aloft could somewhat limit temperatures from reaching their max potential across the northern half of MN and WI.

3.) Any stronger shortwave could beat back the ridge for a day or so.

Confidence is high enough for heat and humidity to reach dangerous levels across southern MN and the metro Saturday and Sunday such that an Extreme Heat Watch has been issued for those areas. With temperatures well into the 90s and dew points in the mid to potentially upper 70s, heat indices should range from 100 to 108. Farther north, vertically integrated smoke modeling shows higher concentrations across northern MN into WI, coupled with dew points remaining in the upper 60s. This should keep the most intense heat at bay, although it is likely Heat Advisories will be needed.

There is a conditional risk of thunderstorm development Saturday night. A strengthening LLJ and very steep lapse rates could lead to this development. However, rising heights and 700 mb temps likely greater than +12C should limit coverage. It does not appear anything will develop on a scale that would negatively impact temperatures for Sunday.

By Sunday night a cold front will approach from the northwest. An unstable airmass with sufficient shear would be supportive of thunderstorms. However, the lack of a strong shortwave and a cap likely remaining could again limit coverage. If storms do develop, there is a risk of them becoming severe.

Behind the front Monday, winds will turn northwest and drier air will work in during the afternoon. If this dry air advection slows, then another day of extreme heat is possible. Confidence is not high enough to extend the watch through Monday at this time. The rest of next week looks seasonably hot, but less humid than this weekend. We will be tallying another long string of 90s to finish out the month. It's possible more than half this month will have highs in the 90s, getting us into the top 10 most number of days of 90+ for July.

AVIATION /18Z TAFS THROUGH 00Z SUNDAY/

Issued at 1219 PM CDT Fri Jul 24 2026

Some pockets of MVFR cigs remain this afternoon, but clouds will continue to scatter out throughout the day. Scattered storms will likely develop over northern MN and eastern ND this afternoon and may move southeast into parts of central MN. Confidence is too low to include in the TAFs, but AXN would be the most likely to see any impacts.

Additional storm development is expected across northern WI during the morning, though some showers or weak storms may form along a boundary extending into east-central MN. Again, confidence is too low to include in the TAFs at this time. It is most likely that all sites remain dry through the period. This influx of moisture in the morning should support the development of lower clouds near 1000-1500 ft, especially across southeast MN and western WI.

KMSP...VFR through the tonight, with the chance for low MVFR cigs to develop during the morning as moisture increases in the low levels. This would also be the best time (around 12-14z) for an isolated shower or weak storm to form as well. A prob30 may be needed if confidence increases for any precipitation tomorrow morning.

/OUTLOOK FOR KMSP/ SUN...VFR, with -TSRA possible late. Wind SSW 10 kts. MON...VFR. Wind SW becoming NW at 10-15G25 kts. TUE...VFR. Wind NW at 5-10 kts.

MPX WATCHES/WARNINGS/ADVISORIES

MN...Extreme Heat Watch from Saturday afternoon through Sunday evening for Anoka-Blue Earth-Brown-Carver-Chippewa-Dakota- Faribault-Freeborn-Hennepin-Kandiyohi-Lac Qui Parle-Le Sueur-Martin-McLeod-Meeker-Nicollet-Ramsey-Redwood- Renville-Rice-Scott-Sibley-Steele-Swift-Waseca-Washington- Watonwan-Wright-Yellow Medicine. WI...None.