textproduct: Grand Forks

KEY MESSAGES

- Frost is forecast early Wednesday morning in northwest Minnesota near Lake of the Woods to Red Lakes area.

- There is a medium chance for showers and weak thunderstorms Wednesday. Additional chances for rain come Friday into the weekend.

..Rain chances ahead

Zonal flow aloft with entrance region of an upper jet will linger over our region through Wednesday, allowing a weak and progressive shortwave trough/upper ascent to migrate west to east across our area. While synoptic forcing is expected to be weak and moisture return meager, an uptick in instability is forecast to accompany this forcing/moisture. This will offer opportunity for thunderstorms of the weaker variety. Very little rainfall amounts are expected with this, despite the convective behavior.

On Friday, a rather robust banded-rain event is expected with strong forcing from frontogenesis fed by rich moisture and instability. Current guidance keeps majority of this rainfall (in excess of 3 inches) south of our area out of eastern SD into southern/central MN. However, given the majority of this forcing driven by mesoscale processes, confidence in location is not great. Thus, there is potential for this banded heavy rainfall to eek into locations near the SD border into west-central MN.

Into this weekend, a more consolidated shortwave trough is progged to translate across the Dakotas into Minnesota west to east. This will bring widespread rainfall chances. However, confidence is low in evolution of this particular wave given its time into the future nearing the predictability horizon. At this time, there is very little evidence to suggest amounts more than 1 inch from this particular wave.

AVIATION /00Z TAFS THROUGH 00Z THURSDAY/

Issued at 633 PM CDT Tue Sep 15 2026

VFR conditions for now and the next 6 hours as cumulus above 5000 ft will dissipate after sunset. northwest winds 10 to 15 kts will become light and variable around the same time. There is the possibility of some patchy fog formation later tonight, but probabilities are only around 20 percent at KBJI and a few spots in the Red River Valley. Will leave out of the TAFs for now, but will continue to monitor. Light and variable winds will pick up out of the southeast less than 12 kts tomorrow morning, with increasing high and mid clouds keeping conditions VFR.

FGF WATCHES/WARNINGS/ADVISORIES

ND...None. MN...Frost Advisory from 4 AM to 8 AM CDT Wednesday for MNZ005-006- 008-009-016.