FXUS63 KFGF 232320 AFDFGF Area Forecast Discussion National Weather Service Grand Forks ND 620 PM CDT Sun Aug 23 2026 .KEY MESSAGES... - There is a level 1 out of 5 risk for severe thunderstorms Monday afternoon and evening. Hail to the size of golf balls and wind gusting to 70 mph will be the main threats. && .DISCUSSION... Issued at 258 PM CDT Sun Aug 23 2026 ...Synopsis... Northwest flow prevails this afternoon into the evening, gradually becoming zonal overnight. Showers and isolated thunderstorms could work into parts of eastern North Dakota overnight as warm air advection increases ahead of an approaching shortwave. Upper flow then becomes slightly southwest late overnight into Monday morning. This will be in response to the shortwave and weak upper low moving across southern Manitoba late Monday into Tuesday. Showers and thunderstorms are expected as the associated cold front sweeps across the Northern Plains into the Upper Midwest, with a chance for isolated severe thunderstorms Monday afternoon and evening. Warm air advection ahead of the front will allow afternoon temperatures to climb well into the 80s across most of the area. Slightly cooler temps return on Tuesday and Wednesday. Rain chances Late Tuesday through Thursday will be minimal, with PoPs increasing once more late Friday into the weekend. ...Isolated Severe Thunderstorms Late Monday... Severe thunderstorm coverage on Monday afternoon and evening will depend heavily on the timing of an approaching cold front. Warm air advection will be strong through much of the day across eastern North Dakota and west central Minnesota; however, with remnant shower activity on Monday morning potentially lingering, this could shorten the window of potential severe weather late Monday. Looking at CAMs, there are several potential scenarios, ranging from potential splitting supercells, to elevated clusters. Model soundings are consistent with nearly straight hodographs as the front approaches, which continue to support splitting supercells and hybrid clusters. As such, a high end scenario supports supercells developing west of the Red River during the late afternoon, with hazards including wind gusts to 75 mph and large hail to the size of golf balls. A more likely scenario would be that we have lingering convective inhibition later into the afternoon, thus delaying convection until later in the evening. This would still support wind gusts up to 70 mph, but would transition into mainly an elevated hail scenario that extends into the early overnight hours. With this later scenario, we could see isolated severe thunderstorms lingering into Tuesday morning across parts of northwest Minnesota. && .AVIATION /00Z TAFS THROUGH 00Z MONDAY/... Issued at 620 PM CDT Sun Aug 23 2026 The main challenge throughout the TAF period will be shower and thunderstorm activity. Thunderstorms near KMOT will push eastward this evening, impacting KDVL before midnight. At KGFK and KTVF, showers are likely, but the probability for thunder is lower, therefore no -TSRA mention at these TAF sites at this time. Clouds will thin out with showers/storms decreasing in coverage Monday morning. Southerly winds of 10 to 14 knots accompanied by a few gusts to 20 knots within the Red River Valley will prevail Monday afternoon. Additional thunderstorm development may occur late Monday afternoon and evening, persisting into the overnight beyond the end of this TAF period. At this time, predictability in where storms form along with their coverage precludes any mention of them within the last few hours of the TAF. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...None. MN...None. && $$ DISCUSSION...Lynch AVIATION...Rafferty