textproduct: Grand Forks

KEY MESSAGES

- Medium confidence chance for severe hail Saturday night across southern North Dakota and west central Minnesota.

- Low confidence nebulous chances for strong to severe storms through early next week.

..Synopsis

While the jet stream is relatively mundane in terms of curvature it will remain firmly overhead directing any transient shortwave activity into the Dakotas and Minnesota over the next several days. With moist southerly flow via the central plains into the northern plains corn advection pipeline dewpoints will easily climb into the 60s the next several days leading to somewhat humid but overall seasonable conditions. We will be in the 70s to 80s most days with an outside shot 90 in the central/southern valley Saturday. Aside from scattered thunderstorm chances the next several days look to be overall a relatively dry stretch with no soaking rains on the horizon and no other eye catching hazard potential as RH stays above 35% and wind stays under 30 mph. Something could certainly pop up but right now the main threat for any hazardous weather stems from thunderstorm activity.

- Saturday Night Storms

A weak 500mb shortwave should be transiting northern Minnesota by 00z Sunday with minimal action expected from this as it remains displaced too far north from the moisture or instability. A trailing inverted trough at 850mb will be the area of focus overnight for initiation with a nice plume of theta-e advection ahead of it. There is however quite a disparity in the placement of the moisture gradient and its northward extent which will also dictate the degree of instability available. We could see a more bullish scenario like the NAM where MUCAPE is in excess of 3000 J/kg or something on the lower end like the RAP with only 1000-2000 J/kg where things stay more south of the area. Unlike instability the shear is more broadly agreed upon with anywhere from 40-50kts (locally stronger scenarios exist). This combined with the fact elevated convection seems to be the only possible evolution given a nocturnal inversion and elevated hailers seem to be the primary hazard. Given the environment (assuming storms form) would think hail anywhere from 1-1.5" on the low end to up to 2.5-2.75" is possible if something closer to the NAM verifies. We'll certainly know more by this time tomorrow. Fro reference the hail we got out in Park Rapids this morning occurred in a very similar thermodynamic environment with markedly less shear if that helps to paint the picture for Saturday.

- Sunday and beyond

As the jet remains overhead no shortwaves are currently standing out in numerical guidance but given 1000-2000 J/kg MUCAPE and Eff shear of 30-40kts most days its certainly plausible to expect numerous days to have storms, the severity of which along with their placement is highly uncertain. The first days that begin to stand out are Tuesday and Wednesday for this potential but will wait until more guidance comes into better agreement to start increasing messaging.

AVIATION /00Z TAFS THROUGH 00Z SATURDAY/

Issued at 620 PM CDT Fri Aug 7 2026

VFR should prevail through the TAF period with a low chance for fog development over parts of west central MN tonight based on the position of the surface high pressure and good radiational conditions. Guidance currently doesn't show a signal for this, so it would likely be very localized to where temperatures are able to drop below 50F. Northwest winds are decreasing as the sun begins to set this evening and light and variable winds are expected due to high pressure. A front will be around the region tomorrow with light southerly winds across southeast ND and west central MN to the south of the front, and winds shifting to the north then northeast north of this front. Prevailing winds should remain below 10kt.

There is an increasing chance for isolated to scattered showers and thunderstorms after the current TAF period Saturday evening for southern locations (chances generally under 30%).

FGF WATCHES/WARNINGS/ADVISORIES

ND...None. MN...None.