textproduct: Grand Forks

KEY MESSAGES

- Showers and scattered thunderstorms are expected to redevelop this afternoon continuing through Wednesday. The main hazard with thunderstorm activity will be lightning.

UPDATE

Issued at 325 AM CDT Tue Jun 16 2026

Update to key message.

The main elevated instability axis is now shown by guidance including the latest HREF to remain west of our region, which lowers the probability for strong or isolated marginally severe storms in eastern ND as weak shear and MUCAPE generally under 800 J/KG is expected over our far west/southwest. The threat is now favored west of our CWA.

The next mid level wave approaches the region during peak heating and mid level lapse rates will still support increasing shower and isolated thunderstorm chances through the afternoon hours (northwest to southeast). Widespread showers and scattered thunderstorms eventually overspreading the region tonight into Wednesday as the main mid level low moves across eastern ND and northwest MN. The probability for wetting rain is highest along and south of Highway 2 in this patter, with the probability for greater than 0.5" above 50% mainly from central ND into southeast ND and across west central MN based on current HREF and NBM 24hr probabilities.

..Isolated Severe Thunderstorms Today

Instability across southeast North Dakota, the southern Red River Valley, and west central Minnesota will be supportive of a few strong to severe thunderstorms this afternoon and evening. Soundings confirm the presence of surface CAPE values generally just below 1000 J/Kg, but with very little shear. Dry air is in place at the surface, which supports a mention of wind gusts; however, with weak CAPE and shear, updrafts are expected to be somewhat short lived. With the taller storms, we could see just enough moisture loading to support 1 inch hail and wind gusts to 60 mph. Many storms, however, will struggle to reach severe strength.

AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/

Issued at 1146 PM CDT Mon Jun 15 2026

VFR tonight with a few gusts still over 15kts but those should drop off overnight. Winds becoming more W/SW tomorrow afternoon with a gentle 10-15kt breeze. Most sites will likely see rain at some point after 22z tomorrow but varying degrees of confidence in rain lead tafs not yet reflecting that deterministically. This will likely change with subsequent updates but felt a simple mention in this discussion would suffice for now. There is a very low probability for MVFR cigs after 00z tomorrow.

FGF WATCHES/WARNINGS/ADVISORIES

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