778 FXUS63 KMPX 250914 AFDMPX Area Forecast Discussion National Weather Service Twin Cities/Chanhassen MN 414 AM CDT Fri Jul 25 2025 .KEY MESSAGES... - Quiet weather through Saturday aside from poor air quality through this evening due to wildfire smoke. - Warming temperatures with highs near 90 and heat indices in the upper 90s to low 100s on Sunday. - Unsettled weather resumes on Sunday and lasts through early next week with daily thunderstorm chances. && .DISCUSSION... Issued at 413 AM CDT Fri Jul 25 2025 Surface high pressure currently resides over the upper Great Lakes region early this morning which is expected to linger overhead for at least 24hrs. Areas of wildfire smoke has once again been advected in from flow aloft. The smoke will take its time to clear as we wait for troughing over NE`rn Ontario to pull it eastward later today. Thus, unhealthy air quality will be present for most especially across northern Minnesota. An air quality alert remains in place for all of MN counties until 11 PM tonight. Aside from smoke concerns, lack of winds and radiational cooling have allowed for areas of dense fog to develop. The fog is not expected to linger long after sunrise but visibilities in a few areas could reach below one quarter mile. Therefore if on the road early this morning, slow down and use low-beam headlights. Once the fog clears, skies will be partly cloudy mixed with suspended wildfire smoke and highs in the mid 80s. By Saturday through Monday, ridging over the eastern CONUS continues to build. Saturday looks dry with mostly sunny to partly cloudy skies although surface flow will be nearly due south meaning dew points are expected to creep into the lower 70s. As an h850 thermal ridge moves eastward into this moist airmass, heat indices by Saturday afternoon will reach the 90s for most to near 100 degrees across western MN. Sunday looks to be even warmer and stickier. Ridging across the south becomes broader and stronger which will only bring more heat and humidity northward. Dew points on Sunday will range in the mid to upper 70s with highs in lower 90s. Heat headlines may be needed especially on Sunday as heat indices reach the upper 90s to lower 100s. Conditions will remains hot and sticky into Monday although Uncertainty remains as to where and how much convection lingers from the previous day. As mentioned in the previous discussion, there is a potential caveat with Sunday`s heating. Similar to what we saw earlier this week and how convection mitigated heat concerns for many. Another round of airmass rain and thunderstorms will be possible Sunday afternoon/evening. With aforementioned ridging occur to our north and east, this places the northern plains in a "ring of fire" pattern. Meaning storms that develop within of regime of strong instability typically travel downstream along the ridge. A factor that differs from earlier this week is the presence of stronger capping. Forecast soundings continue to depict strong capping above the surface thus this environment would require a hefty source of lift in order to tap into elevated instability. Nonetheless, something to watch as we enter the weekend. Should severe weather develop, all hazards will be possible to include heavy rain as PWATs near two inches. Another reprieve from the heat looks to arrive by the middle of next week. Cooler and drier air is progged to follow behind a cold front returning highs back into the upper 70s by Wednesday until the end of the forecast period. && .AVIATION /06Z TAFS THROUGH 06Z SATURDAY/... Issued at 1241 AM CDT Fri Jul 25 2025 MVFR/IFR FU/FG possible overnight. Areas of wildfire smoke have reach as far south of central MN. With virtually no wind currently and forecast over the next several hours, fog is expected to develop in the smoke. The most prevalent impacts are expected at STC, RNH, and EAU where a few hours of LIFR 1/2 vsby is likely. Timing reflects with tempo groups between 09-13z timeframe. RWF and MKT could see fog as well but impacts should only reach low MVFR vsby. Southerly winds will remain light through tomorrow although AXN could see a few gusts between 18-20kts in the afternoon. KMSP...Smoke is moving farther south than anticipated. Thus, have introduced a tempo to capture periods of lowered MVFR vsby early this morning. /OUTLOOK FOR KMSP/ SAT...VFR. Wind S 5-10kts. SUN...Chc morning MVFR cigs. Chc P.M. -TSRA. Wind SE 5-10kts. MON...VFR. Wind NNE 5-10 kts. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...None. WI...None. && $$ DISCUSSION...Dunleavy AVIATION...Dunleavy