543 FXUS63 KMPX 292042 AFDMPX Area Forecast Discussion National Weather Service Twin Cities/Chanhassen MN 342 PM CDT Mon Jun 29 2026 .KEY MESSAGES... - Extreme Heat Warning continues this evening, and Heat Advisory through Tuesday evening south & east. Heat index values approach 110F today, and 100F on Tuesday. - Low chance of thunderstorms this evening, but, if thunderstorms are able to develop they could become severe with heavy rain. - Hot & humid weather continues this week, although not nearly as intense as today. Continued low chances for thunderstorms as well. && .DISCUSSION... Issued at 338 PM CDT Mon Jun 29 2026 It is hot. And it will stay that way for a while, though thankfully today will be the worst of the heat impacts this week. Dewpoints are generally in the mid to upper 70s for the entire region, though some pockets of 80F+ have started to pop up this afternoon. Air temperatures have been stifled a little more than expected by morning convection and afternoon cu field. Heat index values range from 100-110F this afternoon and evening, before getting some relief after sunset. This will be dependent on storm chances late this evening and overnight as a cold front looks to stall across central MN, dividing the state in half vertically. As cooler 700 mb temperatures advect in behind the front, that should provide enough forcing to overcome the cap and intiate at least scattered storms along the line. There is an explosive amount of instability (4500+ J/kg of MUCAPE), so any storms that are able to develop would likely become severe with damaging wind and heavy rainfall. The other thing to watch is a unsuspecting threat for tornadoes given the increasing amount of SRH values around sunset. There is a short 1-3 hour window of STP values jumping to 3+ just ahead of the front as the LLJ increases and surface winds decrease just enough to have a better hump to hodographs. The extent and strength of any potential tornado risk will depend on storm coverage and mode, which is uncertain right now given the widespread variance across hi-res models. There are some models, like the 18z RRFS, which have nothing develop this evening across our area. Because of this variance, PoPs are still limited, but the high end potential should still be messaged. There is a growing signal for early morning convection to advect north from Nebraska and Iowa, especially if we end up seeing less storm coverage this evening. These storms would not have as conducive of an environment for severe development, but they would have an influence on our heat impacts for Tuesday. The more storms and lingering cloud cover, the less of an impact from heat. This is exactly what we saw today across parts of central and northern MN as a bow echo raced northeast. With this uncertainty in storm and cloud coverage, we opted to issue a Heat Advisory for a number of counties across south and eastern Minnesota as well as western Wisconsin. In areas that are not drastically impacted by storms, heat indices are expected to climb to about 100F Tuesday afternoon. As the week progresses, not too much will change with the overall weather pattern. Upper level ridging will continue to dominate the eastern half of the CONUS, keeping the Upper MS Valley on the northwestern periphery of the heat dome. Our hot and muggy conditions will continue with highs anywhere between the mid 80s to low 90s and dewpoints generally in the upper 60s to low 70s. Heat risk will not be as much of a concern as it was today, though the persistent heat will continue to have an impact as it lingers for several days. A frontal boundary may stall out the region, which would provide several opportunities for additional storms through the rest of the week. && .AVIATION /18Z TAFS THROUGH 00Z WEDNESDAY/... Issued at 1244 PM CDT Mon Jun 29 2026 A mix of low VFR to MVFR cigs to start the TAF. Cigs should gradually increase to around 4 to 5kft by late afternoon. Main concern for this period is the threat of thunderstorms this evening. A line of storms should develop across W MN after 00z and trek eastward through the night. It'll gradually weaken as it pushes east and likely doesn't impact our W WI sites. I have introduced a PROB30 as the best option given uncertainty with convection this evening. Cigs will briefly dip to MVFR with any TSRA. Winds S/SE 10 to 15 knots with gusts 20 to 30 knots through early evening with gusts falling off overnight. Winds turn more southwesterly tonight with SW winds prevailing on Tuesday. Additional round of TSRA/SHRA is possible around daybreak, but there is not enough confidence to include in the TAF. W WI sites will see MVFR cigs possible overnight before scattering after daybreak. VFR on Tuesday. KMSP...Cigs will remain low VFR/MVFR through mid-afternoon. There is a chance for -SHRA/TSRA after 04z and a PROB30 has been included. Additional -SHRA/TSRA is possible around 12z Tuesday AM, but left out given lower confidence. /OUTLOOK FOR KMSP/ WED...VFR. Chc -TSRA. Wind SW 10-15G25 kts. THU...VFR. Chc PM -TSRA. S 5-10 kts. FRI...VFR. S 5-10kts. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...Heat Advisory until midnight CDT tonight for Chippewa-Douglas- Lac Qui Parle-Pope-Stevens-Swift-Todd-Yellow Medicine. Extreme Heat Warning until midnight CDT tonight for Anoka- Benton-Blue Earth-Brown-Carver-Chisago-Dakota-Faribault- Freeborn-Goodhue-Hennepin-Isanti-Kanabec-Kandiyohi-Le Sueur-Martin-McLeod-Meeker-Mille Lacs-Morrison-Nicollet- Ramsey-Redwood-Renville-Rice-Scott-Sherburne-Sibley- Stearns-Steele-Waseca-Washington-Watonwan-Wright. Heat Advisory from midnight tonight to 9 PM CDT Tuesday for Anoka-Blue Earth-Brown-Carver-Chisago-Dakota-Faribault- Freeborn-Goodhue-Hennepin-Le Sueur-Martin-McLeod-Nicollet- Ramsey-Rice-Scott-Sibley-Steele-Waseca-Washington- Watonwan-Wright. WI...Extreme Heat Warning until midnight CDT tonight for Barron- Chippewa-Dunn-Eau Claire-Pepin-Pierce-Polk-St. Croix. Heat Advisory from midnight tonight to 9 PM CDT Tuesday for Barron-Chippewa-Dunn-Eau Claire-Pepin-Pierce-Polk-St. Croix. Heat Advisory until 9 PM CDT Tuesday for Rusk. && $$ DISCUSSION...BED AVIATION...BPH