


Area Forecast Discussion
Issued by NWS Grand Forks, ND
Issued by NWS Grand Forks, ND
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850 FXUS63 KFGF 090300 AFDFGF Area Forecast Discussion National Weather Service Grand Forks ND 1000 PM CDT Tue Jul 8 2025 .KEY MESSAGES... - Severe storms are possible, risk level 1 out of 5, late Wednesday evening. - Severe storms risk level 2 out of 5 will develop Thursday afternoon and night. - Heat risk rises to the moderate category Thursday afternoon, but at this point it looks like heat index values will stay below 100 degrees. && .UPDATE... Issued at 1000 PM CDT Tue Jul 8 2025 There are a few locations reporting surface smoke in northeast ND (4-6sm) otherwise smoke is mainly aloft and not in high enough concentrations/causing low enough visibility reductions for addition to weather grids at this time. Near term adjustments were made, otherwise forecast is on track with a weak/spotty radiational fog signal in the southern and northern RRV. UPDATE Issued at 646 PM CDT Tue Jul 8 2025 CU is beginning to clear with low levels decoupling while high live smoke is still lingering over parts of the region. As winds go calm and cloud cover remains clear radiational conditions may once again support fog development during the period of peak radiational cooling Wednesday morning. The signal in guidance is very spotty, and mainly confined to areas in the far north and south. I added patchy fog mention for those areas during the 09-14Z period, but confidence in higher impacts/higher coverage is low. && .DISCUSSION... Issued at 322 PM CDT Tue Jul 8 2025 ...Synopsis... Fairly quiet tonight as northwesterly flow gives way to very weak ridging. A very weak shortwave riding over the top of the ridge tomorrow night will bring a marginal threat for severe weather Wednesday night. Stronger shortwave and a surface trough axis arriving Thursday will bring another marginal chance for severe impacts during the afternoon and evening hours. A trough will be digging into the Dakotas for Friday and off into the Great Lakes on Saturday, fairly open and fast moving although exact impacts will depend on the way previous day`s convection plays out. Another weak shortwave coming through Manitoba to the Great Lakes on Sunday will help push a surface trough into the region. West to southwest flow for the start of the work week will bring more active pattern, but details unknown at this time. ...Marginal severe risk Wednesday night... A shortwave coming over the top of some weak ridging could be the focus of some isolated severe impacts on Wednesday night. Instability will be strong in central ND, as a narrow band of moisture moving back up into the Dakotas. Shear in the central Dakotas is decent, around 30 kts, but weaker further east in our CWA. Forcing is pretty weak during that time period, but looks like there will be some storms developing in central ND and then moving east during the late evening and overnight Wednesday. ...Slight risk Thursday afternoon... Thursday afternoon will see the upper ridge moving east and then flow becoming southwesterly with a surface trough pushing into the region. Shear is still not too impressive, but very strong instability will be out ahead of the surface trough. CAPE is 70 to 90 percentiles higher than climatology for Thursday, and with the stronger forcing there could be enough effective shear for severe Thursday afternoon. Scattered large hail and damaging winds will be possible with some of the stronger cells that develop. ...Heat Thursday... The instability on Thursday will be powered by very warm temperatures ahead of the surface trough. EFI is not as high as temperatures as it is for CAPE, but still a good signal for heat. At this point heat index looks like it will stay below advisory criteria and remain under 100 degrees, but heat risk is up in the moderate category. Will have to monitor to see if trends go higher in the upcoming shifts. && .AVIATION /00Z TAFS THROUGH 00Z THURSDAY/... Issued at 646 PM CDT Tue Jul 8 2025 VFR conditions should prevail across eastern ND and northwest MN through the TAF period, with a low chance for radiational impacts 09-14Z Wednesday morning. 4000-6000 ft agl CU is clearing with low levels stabilizing and winds should become light and variable this evening. There are also still some pockets of high level smoke aloft over parts of the region. Winds increase after sunrise Wednesday with southerly winds gusting 20kt+ mainly in eastern ND during the afternoon. CU should begin to increase (7000-10000 ft agl) in coverage towards the end of the TAF period with increasing chances (20-30%) for thunderstorms Wednesday evening mainly in ND. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...None. MN...None. && $$ UPDATE...DJR DISCUSSION...JR AVIATION...DJR