textproduct: Twin Cities

KEY MESSAGES

- Clearing skies the remainder of today, with clouds returning on Sunday.

- Scattered showers and rumbles of thunder arrive tomorrow evening in southern Minnesota and linger overnight, spreading into western Wisconsin through Monday morning.

- Warm temperatures are expected beginning tomorrow and lasting throughout the week, with Tuesday looking to be the warmest day with highs in the low 90s possible. Alongside the warmth, airmass type daily storm chances are possible during peak afternoon heating.

DISCUSSION

Issued at 247 PM CDT Sat May 23 2026

Stubborn cloud cover continues to linger across the area with a wedge of clearing showing across the eastern Twin Cities metro as of around 2:30pm per satellite imagery. Though stubborn, this cloud cover is expected to gradually erode this evening and overnight resulting in mostly clear skies by sunrise tomorrow with a few high clouds lingering. Some diurnal cumulus is possible by tomorrow afternoon, with increasing cloud cover into the evening ahead of our next chance for isolated to scattered showers and storms favoring southern Minnesota and western Wisconsin. The setup includes an upper level low amidst a narrow but steep upper level trough over western Ontario stretching a warm front over the area earlier in the day, resulting in WAA and temperatures warming into the upper 70s to low 80s making for our warmest day in recent memory. At the same time, a strengthening nocturnal low level jet arriving by the evening will intensify overnight with the leading edge of lower level convergence beginning in southern Minnesota and spreading as far north as the Twin Cities before moving eastwards quickly towards sunrise Monday morning, with most showers and weak storms over WI by sunrise on Monday but some guidance keeping showers and storms ongoing over southern Minnesota until later in the day. Forecast soundings are not particularly impressive, with peak instability of 500-1000 j/kg Sunday evening diminishing to next to nothing overnight as lower level stability takes hold despite the forcing from the LLJ. There is some decent shear right at the onset of precipitation as the low level jet intensifies, however the window of ideal shear is already after the nocturnal inversion starts to build due to the increased surge of WAA within the LLJ. Some elevated storms remain possible, but generally storm activity should diminish overnight with some rumbles of thunder the most likely outcome and no severe weather expected at the moment.

Surface high pressure follows on the heels of the Canadian low pressure system into the middle of the week, with continued low level WAA resulting in above average temperatures throughout, especially on Tuesday and Wednesday which show the best overall surge of lower level warm air. Highs on Tuesday will approach 90 with dew points in the 50s, and while this is not considered humid by any means for temperatures near 90, it may feel a bit more humid than you might expect as we have yet to have a stretch of warmer weather to allow us to acclimate to dew points in the 50s. Low temperatures will also be much warmer than previously, with lows in the mid to upper 50s and even low 60s closer to the highs we saw this past week. The other main feature besides the heat over the week will be chances for airmass-type diurnal thunderstorms, with the best days looking to be Wednesday and Thursday overall. This is due to a developing low pressure system over the northern US Rockies stretching a broad warm front over the northern plains, with this also surging some moisture northwards with a trace back to the Pacific Coast off southern California. While this isn't the Gulf moisture that tends to bring our best thunderstorm days, it is still more than we have had and will thus be worth paying attention to. The key question for Wednesday will be how far north the warm front positions itself, with the EPS showing a consensus of central Iowa for the best easterly winds at the moment, which would keep the stronger chances to our south leaving us within the less stormy but still showery region north of the warm front. Until the position is nailed down, it is too early to say what will ultimately occur. The synoptic setup weakens into the later parts of the week, and although more airmass type storms are possible, there is a lack of significant enough forcing to be too concerned about the potential for severe weather at the moment.

AVIATION /00Z TAFS THROUGH 00Z MONDAY/

Issued at 533 PM CDT Sat May 23 2026

Broken to scattered low-end VFR clouds will push east/dissipate during this evening. HRRR shows a weak surface high pressure developing over east-central MN tonight. This will cause winds within this region to calm while temperatures cool with the clearing skies. Growing confidence of LIFR conditions from fog at STC from 07-13z with visibilities down to 3/4 of a mile and cigs near 500 feet. With its proximity nearby, RNH could see brief moments of mist also near sunrise. Thus, have included a TEMPO for MVFR. Elsewhere, VFR conditions are expected the entire period with few to scattered high clouds after this evening. Westerly winds become calm/variable tonight and then turn south-southwesterly and increase to 5-10 knots during the daytime hours Sunday. Gusts to 20 knots are possible for RWF Sunday afternoon with an incoming LLJ.

KMSP...Winds Sunday afternoon will be southwesterly with sustained values near 10 knots. Added PROB30 from 03-06z Sunday night for a chance of showers.

/OUTLOOK FOR KMSP/ MON...VFR. Wind SW 5-10 kts. TUE...VFR. Wind S 5-10kts. WED...VFR. Wind SE 10-15 kts.

MPX WATCHES/WARNINGS/ADVISORIES

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