


Area Forecast Discussion
Issued by NWS Grand Forks, ND
Issued by NWS Grand Forks, ND
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205 FXUS63 KFGF 111746 AFDFGF Area Forecast Discussion National Weather Service Grand Forks ND 1246 PM CDT Fri Jul 11 2025 .KEY MESSAGES... - There is a level 1 out of 5 risk for severe thunderstorms this afternoon for portions of southeast North Dakota into northwest and west- central Minnesota. Main hazards will be gusty winds to 60 mph and hail to the size of ping pong balls. - Wildfire smoke will degrade air quality behind a cold front today, potentially into the weekend. && .UPDATE... Issued at 1246 PM CDT Fri Jul 11 2025 Getting some pretty hefty updrafts along the front as it moves into an area of ML CAPE in the 1500-2000 J/kg range. Deep layer bulk shear is minimal except well behind the front where there is no instability, so think there could be a few pulse ups to just below severe before coming back down again. Smoke around 1 to 2 miles or even lower visibility continues behind the cold front, even behind the rain so there doesn`t seem to be much washing out. Even though the models show the possibility of some minor improvements to the smoke this afternoon and evening, will continue to keep messaging going. UPDATE Issued at 947 AM CDT Fri Jul 11 2025 Some thunderstorms starting to develop just behind the frontal boundary in the southern Red River Valley. All elevated so far and not much shear to work with, but will have to keep an eye on them for lightning as they approach our DSS sites and in case they become rooted in the boundary layer and intensify. Adjusted POPs for the current radar and satellite trends. Still quite a bit of smoke behind the front, so will continue to keep the mention going. UPDATE Issued at 741 AM CDT Fri Jul 11 2025 As upper/mid trough nears central ND, increased forcing for ascent is leading to scattered showers and thunderstorms. At its current trajectory, this activity will cross the Red River late morning. This activity is not anticipated to be severe during the morning hours due to limited surface based instability as well as low overall shear. Access to better instability is nearby, however, with dew points still near 70 closer and ahead of cold front. It remains unclear whether or not the current, elevated convection within central ND will overlap with the cold front and essentially become surface based leading to severe thunderstorms. Should this occur, there is potential for better shear to overlap with deep convection, perhaps increasing coverage/time for strong to severe storms. Some location differences in severe storm potential also still exists, with one scenario bringing this chance into southeast ND/southern RRV impacting locations like the Fargo-Moorhead metro, or if potential shifts deeper into Minnesota before robust thunderstorm development occurs omitting southeast ND/southern RRV from severe potential. && .DISCUSSION... Issued at 404 AM CDT Fri Jul 11 2025 ...Synopsis... Well developed upper/mid level trough is easily viewable on water vapor imagery migrating through MT and southern SK early this morning. This will provide upper forcing for ascent for showers and thunderstorms along/near a cold front working its way east across ND, eventually into MN this afternoon. Some thunderstorms this afternoon may be severe (more details below). Behind the cold front, smoke from Canadian wildfires is being observed, and will degrade air quality through at least today (more details below). As the upper/mid trough pushes east into the Upper Midwest and western Great Lakes, drier air behind the cold front filters into the region, although there may be some scattered showers and/or weak thunderstorms near northwest Minnesota Saturday afternoon. Northwest flow aloft briefly sets up around Sunday, along with increased shear. Meager instability and lack of more organized forcing will preclude messaging of potential strong to severe storms Sunday afternoon, although if either increases (either from better moisture return and/or added moisture from evapotranspiration; subtle impulse aloft to increase forcing), then this chance increase. Into next week, most ensembles favor low amplitude upper ridging into the Northern Plains and Upper Midwest between Monday and Tuesday, offering a chance for warming trend with increasing low level moisture. This comes ahead of upper troughing extending out of central Canada into the Northern Plains and Upper Midwest mid to late next week. This increases chance for showers and thunderstorms. There is a signal within ensemble guidance that hints at potential heavy rainfall via increased EFI values/probabilities within ECMWF ensemble suite. Increased instabilty and forcing/kinematics from this trough also increases the chance for potentially strong to severe thunderstorms. This is backed up by AI tools like FengWu AI-NWP forecast, namely on Monday into Tuesday. Behind this trough, most ensemble guidance shows a much drier and cooler air mass moving into the region by late next week. ...Severe storm potential this afternoon... Latest high resolution guidance strongly suggests thunderstorms to develop along/near a cold front this afternoon within portions of southeast ND into northwest and west-central MN. While shear is quite meager within the vicinity of thunderstorms, rich moisture and increasing daytime temperatures beneath cooling air mass aloft will aid in moderate to strong instability. Given the lack of overall shear, quick upscale growth of thunderstorms are anticipated, aided by forward momentum of the cold front itself. While shear will be low, there may be enough of an extension of increased flow aloft from the incoming trough to help transfer toward the surface of eventual MCS, also aided by cold pool organization. Thus, gusts to 60 mph will be possible from this activity. There will still be a short timeframe where thunderstorms initially in their semi-discrete mode shortly after initial development will be capable of hail to the size of ping pong balls given the instability that will be in place. ...Degraded air quality today, potentially into this weekend... Surface observations behind the cold front early this morning show wildfire smoke reducing visibility less than 2 miles and AQI values into the "unhealthy" category. This lends confidence that smoke will infiltrate the area behind the cold front at least through today. Guidance also offers another round of near surface smoke behind another cold front around Sunday. It is unclear to the degree in which this may degrade air quality. && .AVIATION /18Z TAFS THROUGH 18Z SATURDAY/... Issued at 1246 PM CDT Fri Jul 11 2025 Thunderstorms developing along the cold front could get close to KBJI and KFAR early in the period, but the more northern and western airports should see mostly showers. Along with smoke down to the surface, which is bringing vis down into the 1 to 2 mile range in many places. Some improvement to visibility is expected later this afternoon and evening, but additional Canadian wildfire smoke will be possible later tonight into tomorrow morning. Some sites will be back up to VFR by mid-day tomorrow but others will be MVFR due to visibility. Winds that are gusting to around 20 kts or higher this afternoon will drop down to around 10 kts, remaining mainly northwesterly and then westerly. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...None. MN...None. && $$ UPDATE...CJ/JR DISCUSSION...CJ AVIATION...JR