textproduct: Twin Cities

KEY MESSAGES

- Coverage of showers and thunderstorms will increase this afternoon and evening. A few storms may be strong to severe.

- Additional showers and thunderstorms are possible across central MN and western WI Wednesday.

- Comfortable temperatures stick around through the end of the week. A pattern change will bring hot and humid conditions with daily storm chances heading into next week.

DISCUSSION

Issued at 135 PM CDT Tue Jun 23 2026

Early afternoon regional radar captures a batch of showers and thunderstorms progressing east across central MN. This activity developed on the nose of the LLJ within a region of warm advection ahead of a surface low positioned near the intersection of northeast ND/northwest MN/southern Manitoba. Aloft, an upper-low near the International Border is supported by a channel of 40-50kt flow across the Dakotas. A few of the cells within the initial round of storms have exhibited broad rotation and some stronger cores as they remain on the line of the of marginal CAPE/shear axis, which will remain possible in the near term. HREF's 12z CAM paintball ensemble captures the ongoing showers/storms pretty well and shows this activity moving ESE and expanding southward with time. RAP mesoanalysis shows that the environment is becoming more favorable for a few strong to severe storms in the wake of the initial batch of showers/ahead of a cold front across the eastern Dakotas/and northwestern MN. This region is characterized by pooling of increasing surface moisture (low 60s dew points) supportive of CAPEs on the order of 1000-1500 J/kg. The influence of the upper-low to the northwest and effective shear on the order of 30-40kts with at some low-level curvature in the hodographs will be supportive of an isolated tornado threat with any convection that develops within this region this afternoon. SPC had added a narrow Slight Risk (driven by 5% tornado probs) east of the Red River Valley south into portions of central MN to cover this potential. See MD #1274 for additional details on this threat. Outside of this zone, the going Day 1 Marginal Risk remains in place along and west of a line from Mille Lacs to Martin counties. Any storms that develop within this region will be capable of an isolated instance of large hail (1"+) and damaging wind (60+ mph). Latest QPF expectations include 0.5-0.75" of rainfall potential with today's convection, which is supported by 1.2-1.3" PWATs. All of this to say, coverage of showers and thunderstorms will increase over the entire forecast area later today, but the best chance for strong to severe storms remains across the western half of the forecast area.

The core of the upper-low is progged to move east across northern MN tomorrow, which will place our forecast area in a post-frontal northwesterly cyclonic flow regime. Shower and thunderstorm chances return along and north of I-94 tomorrow afternoon and evening, with the highest PoPs located in western WI. Speaking of which, we won't rule out a stronger storm or two across our western WI counties tomorrow, but potential increases the farther into central WI tomorrow afternoon. Mainly dry and tranquil weather returns for Thursday, Friday, and most of Saturday. Temperatures are forecast to warm a few degrees each day, with highs back in the low to mid 80s by Saturday afternoon. A change to the pattern will begin to take shape later Saturday, as the eastward translation of a trough over the western CONUS sends a warm front northward into the Upper Midwest. This will more than likely support a round of showers and thunderstorms across the region late Saturday into Sunday morning.

Good ensemble support exists for a jetstreak to round the base of the trough Sunday and promote the maturation and occlusion of an upper-low over south central Canada by Monday afternoon. The Upper Midwest will be positioned east of the developing feature, within a region of southwesterly flow and very warm mid-level temperatures captured by an EML on forecast soundings. The position of the aforementioned warm front will be something to watch, but current expectations support it lifting north of the forecast area allowing for highs to climb into the upper 80s/lower 90s Sunday & Monday. As referenced by the previous discussion, the very warm mid-level temperatures will act as a cap on the atmosphere which casts doubt in convective evolution Sunday into Monday. However, the approach of the upper forcing and weakening of said cap bears watching for deeper, potentially severe convection Monday afternoon and evening as is highlighted by various machine learning tools.

Looking farther ahead, ensembles take a much more Summer look by depicting a 590s dm ridge building over the central CONUS for the middle to end of next week. At the very least, this will support a more prolonged period of heat and humidity heading into July. Dangerous heat and active stormy weather, supported by the first appearance of the classic ring-of-fire pattern, are both possible over the coming weeks. Stay tuned!

AVIATION /06Z TAFS THROUGH 12Z THURSDAY/

Issued at 1235 AM CDT Wed Jun 24 2026

IFR cigs are expanding across central WI and northwest WI. Cigs in this area will deteriorate further overnight and may reach the surface as dense fog closer to dawn. AXN should clear out shortly after the TAF begins as winds turn southwest and push the stratus northeast. IFR conditions will linger into mid morning at STC, RNH, EAU, and possibly MSP before lifting and scattering. Scattered TS will develop in the afternoon, impacting mainly RNH and EAU where prob30s were introduced.

KMSP...IFR cigs are building south from the north metro but guidance brings them to near MSP before stalling, leaving a low confidence forecast. The cigs are sufficiently close to include IFR in the TAF after 08Z.

/OUTLOOK FOR KMSP/ THU...VFR. Wind NW 5-10 kts becoming NE. FRI...VFR. Wind SE 5-10 kts. SAT...VFR. Wind SE 10-15kts gusting to 25kts.

MPX WATCHES/WARNINGS/ADVISORIES

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