textproduct: Twin Cities

KEY MESSAGES

- Long duration period of heat and humidity begins Sunday, persisting through the week. Monday will be the hottest day, but heat impacts to be felt all week with little overnight relief and therefore a building heat stress.

- Chances for thunderstorms exist Sunday through next week. Storms will be capable of severe weather & torrential rain, if they are able to form.

NEXT WEEK

On Monday, the well advertised upper level ridge will be firmly established over the region. In response, heat and humidity will continue to build in across the region, with areawide high temperatures well into the 90s and DP temps in the 70s. That said, there does remain a degree of uncertainty with regard to how potential cloud coverage/precip will impact Monday temperatures. But as of now, we are going to continue messaging the dangerous heat risks Monday poses. Forecast high temperatures on Monday will top out in the middle 90s across much of the area, slightly cooler across northern portions of the CWA, with hottest values across western MN that will approach the upper 90s. Global deterministic models and their respected ensemble/AI ensemble suites continue to show medium to high confidence in temperatures being greater than 90 degrees (60-95%). The hot afternoon temperatures coupled with DP temps in the 70s will lead to dangerous heat index values. This level of heat will be dangerous for anyone without reliable AC, those working and doing strenuous activities outside, young children, older adults, and people with chronic health conditions.

The hot and humid conditions will continue through the work week with daily high temps around 90 degrees. What makes this long duration period of heat so impactful, is the lack of recovery in overnight temperatures. Overnight temperatures through the week will be in the upper 60s and low 70s across the area. This will further build the heat stress that could potentially last into the holiday weekend. With all that being said, the overnight forecast package will not issue any heat related headlines, allowing the daytime crew to assess fresh 12Z data. But like mentioned in the previous discussion, heat headlines are inevitable at some in the next 24-36 hours.

With ample heat, moisture, and instability in place all of next week, the threat for thunderstorms and heavy rain will be at play. Increasing moisture throughout the column with promote PWAT values 120-170 percent of normal, shown by the global and global AI ensemble suites. Hence the threat for heavy rain anywhere storms are able to form. Like mentioned above, with ample heat and instability in place, anywhere convection occurs, it will be rather robust with daily CAPE values at or above 1500 J/kg each afternoon. However, given that each day will feature some sort of capping, confidence is low with regards to timing and impacts on when convection will occur.

To summarize, a conditional severe weather threat is present most (all?) days next week. The key will be to keep a close eye on potential forcing to see what storms may come to fruition. If we tap into instability, things will get interesting storm wise given the highly primed environment. IF storms go, they'll go. It isn't worth the time to try and pinpoint specifics at stage. Once CAMs are available, the threat could be more refined.

AVIATION /12Z TAFS THROUGH 18Z SUNDAY/

Issued at 551 AM CDT Sat Jun 27 2026

VFR through the period with SCT/BKN mid-level clouds. Southeast winds through the period increasing to 10-15 kts by late morning, along with wind gusts of 20-25 kts. Ceilings drop early tomorrow morning with MVFR conditions likely across western & central Minnesota. Showers & thunderstorms approach AXN & RWF around the end of the period tomorrow morning.

KMSP...Decaying showers & thunderstorms are expected to move eastwards across Minnesota through Sunday morning. It's still uncertain just how widespread these showers may be by the time they reach the metro late-morning, & whether they will be robust enough to contain lightning

/OUTLOOK FOR KMSP/ SUN PM...VFR. Wind SE 20G30 kts. MON...VFR. Chc PM TSRA. Wind S 15-20G30 kts. TUE...VFR. Wind SW 15-20G30 kts.

MPX WATCHES/WARNINGS/ADVISORIES

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