


Area Forecast Discussion
Issued by NWS Grand Forks, ND
Issued by NWS Grand Forks, ND
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927 FXUS63 KFGF 041819 AFDFGF Area Forecast Discussion National Weather Service Grand Forks ND 119 PM CDT Sat Oct 4 2025 .KEY MESSAGES... - Near record warmth again today. - There is a level 1 out of 5 risk for severe thunderstorms Saturday evening across most of eastern North Dakota, extending into northwest Minnesota. - Rain over most of northeastern North Dakota Saturday night into Sunday. && .UPDATE... Issued at 119 PM CDT Sat Oct 4 2025 the light rain showers in northeast ND are transitioning north and beginning to decrease in coverage matching HRRR trends. Best coverage is still expected this evening/overnight into Sunday morning as 700MB deformation tracks over our northwest and a LLJ develops in our southeast. The period late this evening into the early overnight near the stalled frontal zone/LLJ corridor will be where a few elevated strong/severe thunderstorms may develop. Forecast is generally on track, and minor adjustments were made. UPDATE Issued at 1008 AM CDT Sat Oct 4 2025 Returns on radar likely associated with the onset of elevated/light showers have spread into the Devils Lake Basin a bit earlier than previous forecast timing, and I adjusted PoPs to reflect these trends. Otherwise, the general forecast trends are on track this morning. UPDATE Issued at 648 AM CDT Sat Oct 4 2025 Towering cu still extending across portions of northwestern MN out ahead of the front in the warm air advection. However, radar returns are a lot weaker than earlier this morning and think the overall activity will continue to dissipate as the low level jet weakens. Made some minor tweaks to POPs for the next few hours, but main show for convection will hold off until later this afternoon and into tonight. && .DISCUSSION... Issued at 343 AM CDT Sat Oct 4 2025 ...Synopsis... Southwesterly flow aloft continues today, with the next significant shortwave coming out of the main trough in the Rockies out into the Dakotas tonight. This will help push a surface trough and cold front into the area tonight and Sunday, finally bringing much cooler temperatures. A bit of uncertainty with the timing of various reinforcing shortwaves as we head into next week, but could see some temps dipping into the 30s during the early mornings Monday through mid-week. ...Heat today... Warm air advection continues overnight, and 850mb temps in the low to mid 20s C will move into our southern counties later today. The wind shift to the northwest is just now entering our far northwestern counties, and should only make it through northeastern ND and the central Red River Valley before stalling out this afternoon. While at least some high and mid cloud will move into the south ahead of the front, there will be a fair amount of sunshine and plenty of southerly winds to keep the boundary layer well-mixed. Southeastern ND and portions of northwest and west central MN ahead of the front will again climb into the mid to upper 80s this afternoon. Record highs are 85 to 87 for Grand Forks and Fargo, so well within reach unless the front speeds up significantly. ...Marginal risk for severe thunderstorms this afternoon and evening... Plenty of warm air and modest dew point near 60 degrees will set up some instability this afternoon and evening. HREF has 80 to 90 percent probability of over 1000 J/kg of cape and even a 40 percent chance for over 2000 J/kg. The best deep layer bulk shear remains behind the cold front, but in the area of instability there is some 25 to 40 kts that would be sufficient if the cap is broken. The forcing won`t really be coming into our area until after peak heating, so severe threat is still conditional and will continue to keep messaging for 1 out of 5 risk or marginal. Hodographs and model soundings seem like hail and damaging wind gusts would be the largest threats. ...Rain tonight into Sunday... ECMWF EFI has 90th to 99th percentiles for high QPF from central ND into northwestern MN. Probabilities from the HREF of over an inch of accumulation over that same area are over 80 percent, but going over 2 inches drops probs down to 20 percent with a few isolated spots up to 40 percent. Full NBM is a little more bullish on heavy rain, with up to 50 to 60 percent probability of over 2 inches of QPF near Devils Lake. Overall, rain looks likely tonight into Sunday, and could see some soaking amounts in some areas. && .AVIATION /18Z TAFS THROUGH 18Z SUNDAY/... Issued at 119 PM CDT Sat Oct 4 2025 Highly variable flight conditions are expected across eastern ND and northwest MN through the TAF period. VFR is currently prevailing in southeast ND and northwest MN, however a layer of IFR to MVFR stratus has formed just northwest of a stalled frontal zone in northeast ND. Trends in observation support this continuing over KDVL and being much more variable near KGFK before guidance shows VFR returning late afternoon. IFR stratus is expected to fill back in as widespread showers develop in northeast ND and parts of far northwest MN (20-30% chances for thunderstorms during the same period). Stratus and showers linger into Sunday, though there should be some improvement back to MVFR as the most organized areas of rain transition northeast through the afternoon. Winds are highly variable due to the stalled frontal zone (southerly east of the front and northerly to the northwest of it). Eventually a stronger cold front pushes through the region Sunday and northwest winds should prevail and increase, with gusts as high as 40kt possible behind that front in southeast ND and west central MN. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...None. MN...None. && $$ UPDATE...JR/DJR DISCUSSION...JR AVIATION...DJR