textproduct: Twin Cities

KEY MESSAGES

- Widespread rain arrives Monday with additional chances later in the week.

- A cooler pattern has arrived with highs in the 60s to low 70s through next week.

DISCUSSION

Issued at 307 AM CDT Sun Sep 13 2026

High clouds are streaming east across the northern Plains and Upper Midwest as a short wave trough begins to dig southeast into ND. This trough will continue southeast today, swinging through MN and WI later this morning. This will bring a chance of showers across southern MN, but dry high pressure in place will limit any amounts to a couple hundredths at best. Clearing skies will occur this afternoon.

The high will slide east to the Great Lakes tonight and warm air advection will begin across the Upper Midwest as a potent trough advances into the northern Plains. Very strong moisture advection will be brought on by a 55 kt LLJ Monday and pwats are expected to increase to just short of 2 inches. Isentropic lift will allow widespread showers to develop across the region, but the trough will swing through quickly and limit the residence time of the steadier activity. Scattered showers and thunderstorms may redevelop behind the main round as moisture advection continues into early Monday evening and a moist warm nose around 800 mb allows elevated instability to increase. That potential will be short-lived as drier air begins to work in as the evening wears on. A front will drape itself from northern WI to southeast MN and northwest IA Monday night. The LLJ will impinge on the front allowing for a band of showers and thunderstorms to continue before sliding southeast Tuesday. The highest QPF will be found in this corridor with 1-2 inches expected.

Zonal flow will continue this week with mid level ridging remaining anchored in place across the southeast and strengthening to 600 dam by Wednesday. A nearly stationary front will be draped from the central Plains to mid Mississippi Valley Tuesday and Wednesday, keeping any shower and thunderstorm chances well to the south. The front may work north later in the week as the ridge builds over the southeast. PoPs increase after Wednesday and remain in the forecast into Friday, accounting for low confidence with timing.

Seasonably cool air will remain in place until further notice with highs in the 60s and low 70s and lows in the 40s or 50s.

AVIATION /12Z TAFS THROUGH 18Z MONDAY/

Issued at 550 AM CDT Sun Sep 13 2026

VFR through the 12z period with light WNW winds and mainly dry weather. The period begins with BKN-OVC high clouds (~10k feet) spreading across the region. It's possible that a few raindrops are observed near RWF/MKT prior to 16z, though we've opted to keep both terminals precipitation free due to dry air in the lowest 5k feet of the column as depicted on forecast soundings. Skies will clear by midday with WNW winds between 5-10kts this afternoon. Winds turn out of the southeast by the end of the 12z period.

KMSP...No additional concerns.

/OUTLOOK FOR KMSP/ MON...-SHRA/MVFR likely, chc IFR. Wind SE 10-15G35kts. TUE...VFR. Wind NW 10-15kts. WED...VFR. Chc MVFR/-SHRA PM. Wind E 5-10kts.

MPX WATCHES/WARNINGS/ADVISORIES

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