textproduct: Twin Cities

KEY MESSAGES

- Storms are expected to develop over eastern North Dakota into northwest Minnesota this afternoon. These will move into western and central MN this evening, with some strong to severe storms being possible before they dissipate overnight.

- There are Slight Risks for both severe weather and excessive rainfall Tuesday afternoon through Tuesday night. Uncertainty remains with what latitude a west to east oriented band of heavy rain will fall Tuesday night.

- Heat and humidity start building again over the weekend, with potential for a heat wave increasing for Sunday into the first half of next week.

DISCUSSION

Issued at 320 AM CDT Mon Jul 6 2026

With an upper ridge axis overhead, we've had pretty quiet weather overnight, with the only cloud cover being convective debris stemming from storms out across NoDak and southern Canada. Those storms are being driven by a shortwave over southern Saskatchewan that will head for northwest Ontario tonight. This will push a cold front into northwest MN later today, a front that will be a focus for thunderstorm chances locally through Wednesday as it slowly sags south through the area.

Today, that front front will likely generate storms in the Red River Valley, where the HREF shows mlCAPE exceeding 3000 j/kg. Deep shear is maybe 30 kts, but as we saw back on the 4th, this level of instability is sufficient to get some occasional severe storms going. Current model consensus favors these storms in the Red River Valley eventually organizing along a cold pool that will push south into western and central MN. This should push a line of storms into western or central MN this evening. These storms will be moving into the MPX area near or a little after sunset and without a LLJ to help sustain them with the loss of daytime heating, these storms are expected to weaken pretty rapidly, with them likely not making it as far south as Redwood Falls or Minneapolis. The initial Day 1 convective outlook does an adequate job of highlighting where we're expecting some severe weather potential in our area. Given the timing of these storms and expected linear mode by the time they get here, our primary severe risk will be damaging wind gusts, with a secondary risk for large hail.

Tuesday through Tuesday night. The main source of uncertainty for Tuesday is how far south will convection from today/tonight push the boundary. Along this boundary, the combination of a right entrance region from a jet streak to the north of Lake Superior and a developing southwesterly LLJ that will overrun the surface boundary will set the stage for a potential heavy rain event. There's still uncertainty with how this unfolds. Will it just be several rounds of loosely organized storms that run along the nearly stationary boundary? Will we manage to develop an organized MCS that travels across MN through the night? No matter which adventure we choose, a swath of heavy rain will result, likely in the form of a 50 or so mile wide swath of 1 to 3 inch rain amounts. In the guidance, you see this rain axis falling anywhere from as far north as Fargo into the Arrowhead (ECMWF), to as far south as Aberdeen into the Twin Cities (GFS/NAM). Typically, we see storms in a setup like this lean into the instability, which would favor a more southern track for these storms. 48 hours out, somewhere near the latitude of St. Cloud looks to be the most likely path for these storms to travel, though that will likely move as we start getting into CAM window today. Besides the heavy rain, this environment will be supportive for severe weather. Strong wind gusts looks to be our primary severe hazard, with a hail threat existing as well. A tornado threat would likely be a very narrow window close to sunset as the LLJ starts to strengthen while some surface based instability still exists.

Wednesday will have the same initial problem as Tuesday. Where does the boundary end up after convection from the night before. As heating/instability build into the afternoon, storms should refire along the front. This currently looks most likely from south central MN up toward Eau Claire (so southeast of the Twin Cities). This will have a severe risk as well, though with limited shear and less instability than what we see Tuesday, that severe risk looks more limited, which is highlighted in the Marginal Risk on the Day 3 convective outlook.

Thursday and Friday will bring high pressure, dry weather and a bit of a reprieve from the heat and humidity as dewpoints fall back into the upper 50s to lower 60s.

For the weekend into next week, models continue to highlight the development of a strong ridge of the central CONUS, with h5 heights in excess of 600dm expected by the start of next week somewhere over the central CONUS. We are seeing models converge toward that ridge encompassing MN by Sunday and continuing to do so into early next week. By Monday and Tuesday, the highest quartile of EPS members at MSP are topping 100 for highs, so there's some high end heat potential we'll have to be on the lookout for as that portion of the forecast draws closer.

AVIATION /12Z TAFS THROUGH 18Z TUESDAY/

Issued at 552 AM CDT Mon Jul 6 2026

VFR for most of the period with increasing CIG coverage and lowering towards the tail end, as a decaying line of showers and storms moves into the region from the northwest tonight. The best chance for -TSRA is at AXN, with a prob30 also for STC but most guidance failing to see this line all the way through to MSP and into RNH/EAU. Winds are light and variable to start, leading to some patchy BR in EAU, favoring 160-180 with speeds generally under 7kts. MVFR becomes more likely after the end of the current period and into the next.

KMSP...Kept the TAF dry for now, although there is a chance that the decaying line of showers and storms makes it to the terminal. This will remain uncertain until the storms actually form and we can begin to track them.

/OUTLOOK FOR KMSP/ TUE...VFR, chc PM -TSRA/MVFR. Wind SW 5kts. WED...MVFR/SHRA likely, chc IFR/-TSRA. Wind SW to NW 5-10kts. THU...VFR. Wind NE 5kts.

MPX WATCHES/WARNINGS/ADVISORIES

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