textproduct: Grand Forks

KEY MESSAGES

- Showers and thunderstorms are likely Monday, and a few strong thunderstorms may develop Monday afternoon. Lightning and small hail would be the main threats.

UPDATE

Issued at 310 AM CDT Sat Jun 13 2026

Update to Key Message to account for strong thunderstorm potential Monday afternoon.

There is increasing consensus on a progressive shortwave trough dropping out of Canada Monday with a period of more organized forcing supporting showers and wetting rain (0.1"), with enough elevated instability to support scattered thunderstorms embedded within larger areas of showers. There is a medium chance (30%) for rainfall totals Monday greater than 0.25" which considering the progressive nature of this wave in north-northwest flow would likely require thunderstorm activity for those values to be realized. There isn't currently a signal for severe thunderstorms with this pattern, however 2-6km lapse rates around 7.5 C/km could support marginal elevated instability profiles, with a chance for MUCAPE greater than 1000 J/KG over parts of the region. DCAPE is shown by current guidance to be lower than 800 J/KG and effective shear less than 25kt. Considering the weaker shear and generally marginal nature of the elevated CAPE profiles, severe risk is minimized. Lower freezing levels though do raise the potential for sub-severe hail, with a lower chance for marginally severe hail (1").

UPDATE Issued at 1144 PM CDT Fri Jun 12 2026

Fairly quiet currently with most of the rain showers north of the international border. Another shortwave rotating around the base of the upper low will bring some more clouds, some showers, and cooler temps for tomorrow. HREF has some fairly high probabilities of at least 0.01 inch across our far north, so bumped up POPs a bit from what base NBM gave us. Instability is minimal and only impacts would be some brief light rain.

..Synopsis

Upper low across central Canada will remain in place through at least the next week. Ensemble guidance in good agreement leading to higher confidence with the overall synoptic pattern. The main uncertainty will be the individual shortwaves rounding the main upper low that will lead to shower chances across our region. All in all anticipate period shower chances and cooler temperatures. Impacts should be minimal given lack of instability. There could be a few sneaky marginal severe days (especially for hail given the lower freezing levels) if evapotranspiration from crops provides additional boundary layer moisture.

AVIATION /12Z TAFS THROUGH 12Z SUNDAY/

Issued at 627 AM CDT Sat Jun 13 2026

MVFR ceilings will overspread northeast ND and northwest MN this morning out of Canada (north to south) with improvement back to VFR by this evening for most TAF sites (slower improvement at KBJI). West-northwest winds are increasing and gusts around 30kt are likely late morning and early afternoon over parts of eastern ND including KGFK. A mid level wave should bring scattered very light showers (sprinkles and virga) to northeast ND and northwest MN late this morning into the early afternoon. KFAR currently has the the lowest chance for MVFR ceilings and rain today, and probabilities were too low to include in TAF at this time (may remain north and east).

FGF WATCHES/WARNINGS/ADVISORIES

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