524 FXUS63 KFGF 282123 AFDFGF Area Forecast Discussion National Weather Service Grand Forks ND 423 PM CDT Sun Jun 28 2026 .KEY MESSAGES... - Risk of severe storms tonight and Monday. All hazards are possible. - Potential for heat impacts next week, including the Fourth of July weekend. && .DISCUSSION... Issued at 331 PM CDT Sun Jun 28 2026 ...Synopsis... Well established upper trough over the northern High Plains into southern BC/AB is promoting southwesterly flow aloft over the Northern Plains into Upper Midwest, with an expansive upper ridge over the eastern half of the CONUS. This pattern is promoting moderate to very strong instability over portions of the Dakotas and Minnesota, along with moderate to strong available shear to organize thunderstorms should they develop. This will provide ingredients for severe storms to develop tonight and/or Monday. More details on these below. There is potential for minor heat related impacts Monday afternoon as very high moisture (upper 70s dew points) combine with temperatures into the 80s, perhaps low 90s, in southern Red River Valley into west-central MN. Later in the week, additional heat-related impacts are possible. This includes the Fourth of July weekend. ...Severe storm potential tonight... Despite favorable instability and shear parameter spacing, there is a general lack of focused ascent to spark and sustain severe storms this afternoon. Thus, general trend in our messaging has been to omit severe risk from this afternoon. During the overnight, focus for ascent may become more prevalent near central ND, perhaps allowing some isolated elevated supercells into northeast ND early tonight. This activity would be capable of hail to the size of golfball before quickly pushing into Canada. Couldn't rule out severe storms moving into southeast ND from SD late tonight / early morning Monday. Should this occur, very large hail in excess of 2 inches may be possible, as well as very gusty winds to 80 mph. This scenario is low in confidence, however. ...Severe storm potential Monday... While there is a deft in features to help force thunderstorms to life today, much better forcing will come tonight and Monday as a surface low pressure deepens within eastern Dakotas, propagating northward into Canada by Monday afternoon. Additionally, richer low level moisture (comprised of surface dew points in the mid to upper 70s) will likely overspread portions of eastern ND and northwest into west-central MN. This is also a result of the jet aloft overspread these regions, increasing overall shear. Latest guidance offers a couple of scenarios that could unfold: 1) Well developed severe storms move out of South Dakota into eastern ND traveling northeastward. These storms would be capable of large hail (perhaps very large hail in excess of 2 inches) and gusty winds (perhaps very gusty winds up to 80 mph). These storms start elevated in altitude and nature, becoming more surface based into the afternoon. This would eventually introduce potential for tornadoes among other hazards like large hail and gusty winds. Given the very unstable airmass and strong shear, couldn't rule out strong tornadoes (EF-2+). Thunderstorms begin to exit to the north and east late afternoon into early evening. 2) Overnight thunderstorms within SD diminish before reaching ND, allowing a lull period in the morning. This is before robust thunderstorm development near the surface low that propagates northward through our area by early afternoon. This activity will likely reach severe thresholds, potentially significantly severe - especially if storms can remain more discrete and surface based. This would keep large to very large hail and risk for tornadoes at the forefront of hazards, with an attendant isolated damaging wind risk as well. In this scenario, strong tornadoes again couldn't be ruled out (EF-2+). Again, both scenarios hold the risk for tornadoes (potentially strong). At this time, relatively higher chance for tornadoes exists near and just ahead of the surface low within northeast ND to northwest MN during the afternoon. Uncertainty still exists in overall convective evolution that would dictate storm mode as well as whether or not storms would be more surface based or elevated. More elevated storms would have a hail-forward hazard, whereas surface based storms would allow for all hazards. && .AVIATION /18Z TAFS THROUGH 18Z MONDAY/... Issued at 331 PM CDT Sun Jun 28 2026 MVFR and IFR ceilings are forecast through much of the TAF period. There is medium to high confidence in this occuring at most sites through at least 06Z. Timing of more predominantly IFR ceilings is a bit lower in confidence, with general expectation for this to occur after 06Z. There is potential for fog, perhaps dense, between 09Z-15Z. Confidence in this occuring is rather low. Confidence decreases further in the TAF forecast after 12Z Monday. This stems mainly from potential thunderstorms moving through the region Monday morning. Should this occur, thunderstorms will be capable of erratic gusty winds and hail, in addition to lightning. Winds will generally be between 7-15 kt out of the southeast turning more easterly after 06Z. It is worth mentioning that smoke aloft will also be present within the region this afternoon through tomorrow. At this time, visibility reductions from smoke near the surface is not anticipated. && .FGF WATCHES/WARNINGS/ADVISORIES... ND...Heat Advisory from noon to 8 PM CDT Monday for NDZ039-053. MN...Heat Advisory from noon to 8 PM CDT Monday for MNZ002-003-024- 027>032-040. && $$ DISCUSSION...CJ AVIATION...CJ