


Area Forecast Discussion
Issued by NWS Grand Forks, ND
Issued by NWS Grand Forks, ND
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025 FXUS63 KFGF 071608 AFDFGF Area Forecast Discussion National Weather Service Grand Forks ND 1108 AM CDT Mon Jul 7 2025 .KEY MESSAGES... - Scattered thunderstorms today, a few may be severe with damaging wind gusts or hail to 1.50 inch. The risk of severe storms is a 2 out of 5 for parts of the Red Rive valley. - Isolated severe storms possible Wednesday afternoon or evening, risk level 1 out of 5. - Increasing risk for severe storms into Thursday, late in the day and night. && .UPDATE... Issued at 1108 AM CDT Mon Jul 7 2025 Trended pops and sky grids to current radar/satellite and adjusted into the early afternoon. As the southern activity translates east/continues to fester, could see an increase in strength with that being the main threat for severe activity in the southern half of the area through the afternoon/early evening. Then expect additional development in the north by mid/late afternoon through early evening, with strong to severe thunderstorm chances in the north half of the region. Little changes from overall severe threats of mainly damaging winds and hail threats with greater severe threats further to the south and west across South Dakota/Nebraska, etc. && .DISCUSSION... Issued at 329 AM CDT Mon Jul 7 2025 ...Synopsis... Busy 500 mb pattern with zonal flow more or less and short waves moving into British Columbia and then often taking a dive southeast toward our area. This continues this week and likely beyond. Thus periodic t-storm chances with severe risk dependent on instability, forcing and 0-6 km bulk shear values. ...Severe Risk Today... This early Monday morning SPC meso analysis has a broad 850 mb moisture advection over the area with 25kts 850 mb south winds focus into Jamestown, Devils Lake area. There has been a slow increase in mid level showers in this area since 06z. Main upper wave is in Saskatchewan and giving an area of shower and t-storms with it southeast of Saskatoon. This wave will will be near the Manitoba/ND/MN border at 00z Tue. Thus the idea in pops is to have a lower pop to start today in E ND but increase pops into categorical range north valley later this aftn/eve. Considerable cloud cover today in that area may prevent a lot of sfc heating and MUCAPE in that area remains sub 1000 j/kg. But with cold pool aloft with 500 mb wave moving over cannot rule out some hailers with storms in the north valley. Multi-cell likely as 0-6 km bulk shear may not be strong enough to maintain supercells. Farther south there does appear to be a wave at 500 mb that will move east thru northern SD into northeast SD by late today. Doesnt seem to be picked up well by models. But with this area the area east of it will have more surface heating and a bit higher dew pts with MUCAPES in the 1500 j/kg range. 0-6 km shear not great, but signals from SPC HREF does indicate higher intensity and longer track UH tracks along the SD/ND border late this aftn. SPC did extend slight risk a bit farther north for this. Not much support for strong/severe storms once you get past 02z, with lingering activity likely to exit fcst area around 06z-7z. Tuesday will see high pressure move in and dry conditions. ...Wednesday Severe Risk... Wednesday late aftn/eve will see a short wave move ESE across the area. The airmass advecting north into the area, esp central ND, is more unstable with MUCAPES over 3500 j/kg and high temps in central ND fcst to be low 90s. 0-6 km shear is 30kts or less though. SPC did insert a marginal risk for eastern and central ND due to instability being quite high and weak wave moving ESE thru the area. ...Thursday.... Thursday afternoon and night has for the last several days been highlighted as the most unstable day in the 7 days. MUCAPE values from ensembles (EC/GEM,GFS) from 00z runs all over 3500 j/kg with likely over 4000 j/kg. But issue is placement of 500 mb system with this and placement of 500 mb jet. Model continuity has been poor. Thus question is with all the instability will there be enough forcing and shear aloft to generate a higher end severe threat. That remains to be seen. Given the conditions fcst all hazards would be possible, though wind/hail favored vs tornado as unsure of any surface boundary location. We also have some sfc CIN to overcome. But highs are forecast to be low 90s and dew pts low 70s. If either one can over achieve that will add to instability. For Friday and Saturday forecast hangs on development of 500 mb low and placement and track. GFS been all over the place in the last 24 hours with ECMWF the most consistent in having upper low in the area Saturday with persistent area of showers and t-storms near and just east of the wave over much of the area Friday. Slower ECMWF would keep rain chance longer into Saturday vs NBM. && .AVIATION /06Z TAFS THROUGH 06Z TUESDAY/... Issued at 1044 PM CDT Sun Jul 6 2025 VFR skies tonight with some overnight rain/thunder in DVL (06z to 12z). A little more confidence after 12z in showers across eastern ND and into MN by 18z or so. Thunderstorms likely in the afternoon (18-00z) but weak forcing will contribute to low spatial predictability. Winds will be calm tonight becoming SW in the afternoon Monday and NW in the evening behind the front and wave of storms. Should MVFR conditions occur it will be due to thunder/rain showers at taf sites. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...None. MN...None. && $$ UPDATE...MJB DISCUSSION...Riddle AVIATION...Riddle