textproduct: Twin Cities

KEY MESSAGES

- Multiple rounds of thunderstorms expected Sunday through Monday. Greatest chances for severe thunderstorms are Sunday evening & monday afternoon/evening.

- Damaging wind gusts are the most likely hazard with the strongest thunderstorms Sunday evening through Sunday night. Large hail & a few tornadoes are possible earlier in the evening across southwest Minnesota.

DISCUSSION

Issued at 227 AM CDT Sat May 16 2026

Anvil cirrus continues to clear off to the east overnight, meaning we'll see plenty of Sun to kick off what is shaping p to be a very pleasant Spring Saturday. Very dry humidity values are expected for one more day, but lighter winds today will mitigate any high fire weather concerns. Temperatures will top off around 80 degrees this afternoon.

Clusters of thunderstorms are expected to develop late this afternoon & evening near the SD/NE/IA border region & likely become severe. Models have all come into consensus for the most part this evening with keeping these storms south of the IA/MN border today, so not expecting any weather concerns through this evening. There is a chance that some residual convection on the north side of the thunderstorm complex to our south could bring some showers & thunder to southern Minnesota, but this would have a low chance at becoming strong to severe. Models then become widely varied on what happens Sunday morning, with the legacy/AI global-scale deterministic models all favoring some sort of widespread showers & thunderstorms across much of the area, but high-resolution models remaining either dry or much more sparse in terms of precipitation. Wile this morning precipitation likely won't contain any severe weather or heavy rainfall, it will influence what kind of environment we can develop for potential severe thunderstorms later Sunday afternoon & night.

Sunday still looks to have the better environment for severe weather across our area, as very steep lapse rates potentially lead to CAPE values up to 2000-3000 J/kg during the afternoon/evening along with deep shear values increasing over 50 kts. However, the amount of instability later in the day will ultimately depend on what kind of precipitation (if any ) we see Sunday morning, & how long that cloud cover lingers into the afternoon. The general consensus idea from the high- resolution models is that a few discrete storms will form over the eastern Dakotas/central Plains during the afternoon, potentially remaining discrete as they move northeastwards into southwest Minnesota by early evening. These initial discrete storms could become supercellular given the wind shear values, meaning large hail (potentially 2-3" in diameter) & a few tornadoes are possible along with damaging wind gusts. These storms are then expected to merge into a line of storms, or multiple line segments, & continue eastwards through Minnesota & into Wisconsin through the late evening & overnight hours. Damaging wind gusts will be the primary threat once this transition to a linear storm mode occurs, with the threat likely waning across eastern Minnesota & western Wisconsin as the storms begin to weaken towards midnight & later. We'll have to monitor the timing trends as high-resolution models still remain varied on when the initial storms initiate to our west & how long the event takes to unfold as storm move east into Wisconsin. In general, the earlier storms develop & move into Minnesota, the greater chance we'll have for severe weather with this event.

Confidence greatly decreases once we get past the storms Sunday night, but another environment favorable for severe weather could develop Monday afternoon & evening. However, how Monday unfolds will depend greatly on how the storms Sunday night unfold, & whether we see any secondary clusters of thunderstorms continue on into Monday morning. Generally, Monday's threat does look to be more favorable south of our area across Iowa & southern Wisconsin, but we'll have to monitor how the atmosphere evolves through the day on Monday & where any residual outflow boundaries may set up.

In addition to the chances for severe weather Sunday-Monday, the thunderstorms will also bring our first chance at a soaking rainfall for much of the area this month. Sunday night's storms have the best chance at producing a widespread soaking rainfall, with HREF/REFS probability-matched precipitation indicating amounts of 1-2" possible, although locally higher amounts are certainly possible. Another round of soaking rain is possible Sunday depending on where those storms end up. We do look to dry out & return to seasonably cool temepratures once we get past our stretch of active weather through Monday.

AVIATION /18Z TAFS THROUGH 18Z SUNDAY/

Issued at 1240 PM CDT Sat May 16 2026

VFR and quiet to open the 18z period with northwesterly winds and a few high clouds over central MN. Winds will relax this evening and turn easterly overnight. The new TAF package includes the addition of stronger easterly wind gusts after 12z, with peak gusts forecast to top out near 30kts tomorrow afternoon. The main focus of the period will be timing and areal coverage of shower and thunderstorm chances near and after daybreak Sunday. Latest hi-res models depict a few thunderstorm complexes lifting north out of IA into southern MN/western WI early Sunday. The trend today has been for the greatest coverage of precipitation to almost "split" the terminals to the northwest and southeast, which does add uncertainty into the new PROB30 windows. Conceptually, there should be a precipitation shield on the leading edge of a northward advancing moisture surge tonight, so we've opted to include -SHRA mention at all terminals and will look to forthcoming TAF packages to refine timing. Additionally, we included a TS mention at MKT/RWF given the marginal instability captured on forecast soundings across southern MN. Weather conditions will dry out following the morning round of showers and storms with gusty easterly winds and BKN high MVFR to low VFR ceilings.

KMSP...Northwesterly winds relax this evening and turn easterly heading into Sunday. Peak gusts of 25-30kts are expected tomorrow. We've maintained a PROB30 from 13-18z for rain showers shortly after daybreak. We've leaned on a blend of hi-res and legacy global models to run with the 5-hour PROB30 window. It's possible that we may need to add in a TS mention based on observational trends tonight, however confidence was too low to include at this distance.

/OUTLOOK FOR KMSP/ MON...-SHRA/-TSRA likely, IFR/MVFR. Wind NNW 10-15G20kts. TUE...VFR. Wind WNW 10-15G25kts. WED...VFR. Wind NNW 5-10kts.

MPX WATCHES/WARNINGS/ADVISORIES

MN...Red Flag Warning until 9 PM CDT this evening for Benton- Douglas-Kanabec-Mille Lacs-Morrison-Todd. WI...None.