


Area Forecast Discussion
Issued by NWS Grand Forks, ND
Issued by NWS Grand Forks, ND
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568 FXUS63 KFGF 080835 AFDFGF Area Forecast Discussion National Weather Service Grand Forks ND 335 AM CDT Tue Jul 8 2025 .KEY MESSAGES... - Severe storms are possible, risk level 1 out of 5, Wednesday evening and late Thursday afternoon and night. && .DISCUSSION... Issued at 314 AM CDT Tue Jul 8 2025 ...Synopsis... The 500 mb short wave that has been riding the border is moving east with the last of the rain and t-storms moving out of the Lake of the Woods. Thus for today into tonight and most of Wednesday a dry period for eastern ND and northwest and west central MN. Weak high pressure moving in. We have patchy fog and low clouds currently at 08z and may well see more expansive area of that heading thru 12z, before burning off/clearing off mid morning. Once any fog/low clouds go away, it will turn out to be a partly cloudy day with likely some aftn CU due to surface heating and remains of 850 mb moisture. Clear Tues night into Wed AM with winds turning light southerly. ...Severe chances Wednesday... Wednesday daytime hours look dry with an increasing south- southeast wind. Near 90 Devils Lake to 80s farther east. We wil start to see the spread north of low level moisture in terms of dew pts near 70 late in the day into DVL region, vs upper 50s in north central MN. 850 mb winds south-southwest 25 kts along with warmer and more moisture moving in at 850 mb will bring the risk of elevated convection Wed evening and night. There is also a weak short wave, but that looks to be south in South Dakota. Therefore uncertain on coverage of storm development Wed eve/night. Hence isolated marginal risk. ...Severe chances Thursday... South winds will continue to bring up low level moisture as dew pts reach the low 70s all areas by Thursday aftn. Local dew pts mid or upper 70s due to evapotranspiration. Temps around 90 for highs. The stage is set for Sfc CAPE values to reach 3500-4000 j/kg. Warmer temps at 700 mb and soundings show a warm layer but not strong enough I think to hold back convective development. GFS/ECMWF generally indicate weakening cap 21z-00z. If temps can warm as forecast and dew pts are as fcst...GFS soundings show 4500 j/kg sfc CAPE and minimal CIN at 00z Fri in eastern ND. But there are negatives such as a positive tilt on 500 mb trough to our west and thus no real cooling in the 500 layer. Weak sfc trough will be well out ahead of the 500 mb trough with a weak boundary, wind shift, line likely somehwere from northeast to south central ND at 00z. Some weak short waves may also be present per GFS. All in all, stage is set that if storms form they could be explosive with all hazards late Thu aftn/night. SPC is cautious based on the above and has area in level 1 out of 5 (Marginal) for Thursday in our area based on some of the negatives against explosive severe storm development. Going into Friday and Saturday.... 00z GFS/ECMWF and most ensembles now support a faster exit of the 500 mb wave and not a closed 500 mb low that has been showing up in some past runs. If that is the case, then precipitation chances will move out Friday night. Another in the endless stream of short waves moves ESE to near Winnipeg (ECWMF) or central Manitoba/Saskatchewan (GFS) with chance of storms late Sunday or Monday but small chances at this time due to uncertainity how far south the wave travels toward the border. && .AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/... Issued at 1142 PM CDT Mon Jul 7 2025 Thunderstorms have moved away from the TAF locations this evening, with drying conditions and SCT clouds. Overnight winds go light and variable for some locations, while others remain light out of the north. There is a chance for some patchy fog overnight within the Red River Valley and into lakes country as recent rain and light winds may allow for a few patchy dense locations. This would bring ceilings down to MVFR with potential IFR in the dense portions of the fog. Otherwise, we expect VFR conditions post 12z for all TAF locations. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...None. MN...None. && $$ DISCUSSION...Riddle AVIATION...Spender