textproduct: Grand Forks

KEY MESSAGES

- Slightly cooler and drier through tomorrow before warmer temperatures and shower and thunderstorm chances return for the weekend.

DISCUSSION

Issued at 229 PM CDT Wed Aug 26 2026

Upper troughing continues to move off into the Great Lakes, leaving the Northern Plains under northwesterly flow aloft tonight with surface high pressure. With decreasing clouds tonight and light winds, can't completely rule out some patchy ground fog although the HREF probabilities of visibility less than 1 mile is minimal. Upper ridging builds back into the Western Plains late tomorrow, with most models agreeing on a weak shortwave coming over top of the ridge on Friday. Mean CAPE values look fairly unimpressive Friday except in our far southwestern counties. A few of the machine learning solutions have some probability of severe impacts in portions of our west on Friday, but some tend to run a bit more bullish than reality, so will hold off messaging but continue to monitor.

With the upper ridge coming down and southwesterly flow aloft setting up until a trough comes through the international border region Monday, it looks like there will be an active pattern into the weekend. At least some instability according to the NBM mean CAPE, but spread among the members is almost as much as the mean values, 500-1000 J/kg. Predictability is too low to message any severe impacts at this point but chances look pretty good for showers and thunderstorms given the forcing and time of year for Friday and the weekend. Ensemble means and clusters have mostly southwesterly flow aloft into next week, so expect warmer than average temperatures and periodic precip chances to continue.

AVIATION /00Z TAFS THROUGH 00Z FRIDAY/

Issued at 652 PM CDT Wed Aug 26 2026

VFR conditions should prevail through the TAF period across eastern ND and northwest MN. Northwest winds 10-12kt should continue to decrease this evening after sunset, along with surface high pressure building over the region tonight. There is a chance for ground fog to develop during the early morning hours Thursday with good radiational conditions, however there is enough drier air off the surface that coverage would be limited and it would tend to be very shallow. No guidance currently shows fog development or impacts at TAF sites, so this will be something we can monitor.

FGF WATCHES/WARNINGS/ADVISORIES

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