FXUS63 KMPX 192354 AFDMPX Area Forecast Discussion National Weather Service Twin Cities/Chanhassen MN 654 PM CDT Tue Aug 19 2025 .KEY MESSAGES... - Small chance (10 to 20%) for showers and thunderstorms this afternoon. The threat for severe weather is very low. - Another round of dense fog possible tonight into Wednesday morning. - Dry weather for the most part, aside from showers and thunderstorms along a passing cold Thursday night into Friday. The threat for severe weather and heavy rain is low. && .DISCUSSION... Issued at 1150 AM CDT Tue Aug 19 2025 TODAY...Morning fog has lifted across the region, and some fair weather cumulus has developed. For the rest of today, afternoon heating will continue, allowing instability to build across the region. Forecast soundings show around 1000 J/kg of uncapped instability, so did add a small chance (10 to 20 percent) for some isolated afternoon showers and thunderstorms. The wind shear profile is the limiting factor, with a unidirectional northwest direction, and light speeds less than 25 kts up through 200 mb. For that reason, the risk for severe weather is very low, and the Storm Prediction Center only has general thunder across the region. TONIGHT...Skies will clear after sunset, and winds will be light as surface high pressure remains in place to the northwest. This will set the stage for another round of fog, especially in the low lying areas near bodies of water. WEDNESDAY THROUGH MONDAY...Expect more dry weather, with winds becoming more easterly on Wednesday, and southerly on Thursday as the surface high retreats eastward. The next chance for rain will come late Thursday into Friday morning as a cold front moves across the region. Rain chances are around 70 percent in western Minnesota, but these decrease as the front moves through overnight. The risk for severe weather is low across the region, but there is a Marginal Risk across the far northwest part of the forecast area. The main threat would be damaging wind, or large hail. Once this front moves through on Friday, expect much drier and cooler for the weekend. Dewpoints will decrease throughout the day on Friday as northwest winds usher in a cool, Canadian airmass. Looking ahead to Saturday, expect increasing clouds as the cool air aloft together with late August sun sets the stage for afternoon cloud development, and possibly some scattered showers or thunderstorms. For now, have a mainly dry forecast, but wouldn't be surprised to see small rain chances Saturday afternoon/evening. Lastly, it will feel a bit like fall next week, with highs on Sunday and early next week will only be in the 60s, with lows in the 40s. && .AVIATION /00Z TAFS THROUGH 00Z THURSDAY/... Issued at 653 PM CDT Tue Aug 19 2025 Likely MVFR/IFR BR/FG to develop later tonight across all sites. Iso SHRA/-TSRA continue to move south and east away from our Wisconsin sites early this evening. Farther west, few to sct cigs should transition to clear over the next few hours. As this occurs, MVFR/IFR fog is expected to develop mostly after 8/9z tonight. AXN and RWF look to be impacted the least with only 3 to 4SM likely whereas farther east for all other sites can expect 1SM if not lower. Will need to monitor trends as the night progress and potentially amend for areas of dense fog. By 14z, fog should mix out and give way to improved cigs/vsby. Low diurnal SCT to BKN cigs anticipated to develop again tomorrow afternoon especially for our eastern sites . Light and variable winds tonight becoming northeasterly around 5kts tomorrow morning. KMSP...Main impact continues to be the potential of MVFR cigs arriving late tonight around 8/9z and linger until around 14z Will need to monitor fog/br development but for now, vsby does not look to fall under6SM. Northerly winds becoming light then shift northeasterly tomorrow morning. /OUTLOOK FOR KMSP/ THU...VFR, chc MVFR/BR early. Wind S 5kts. FRI...VFR, chc -SHRA/MVFR. Wind SW to NW 5-10kts. SAT...VFR. Wind NW 10-15kts. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...None. WI...None. && $$ DISCUSSION...JRB/TDH AVIATION...RMD