textproduct: Bismarck

KEY MESSAGES

- Temperatures favored to remain near to slightly above normal until late next week.

- High chances for showers and thunderstorms late Sunday evening through Monday night. There are medium to high chances to exceed 1 inch of rain from south central to northeast North Dakota. A few storms could be strong.

DISCUSSION

Issued at 145 PM CDT Sat Sep 26 2026

Currently a cold front is sweeping through the state west to east, clearing out the low stratus clouds. Behind the front winds are gusting up to 30mph. This trend will continue through the evening. In the low stratus mist and sprinkles are falling, reducing visibilities at times. Aloft a large broad trough has formed across the Pacific Northwest. The rest of this weekend will be in the 60s to lower 70s. That broad trough will bring southwest flow back into the state Sunday, leading to showers and thunderstorms beginning Sunday evening south of the interstate. After sunset, the chances will increase as a disturbance from the Rockies forms a surface low and moves into the Dakotas.

Showers and thunderstorms will continue through Monday as a shortwave and front move in behind the low. There is a chance for thunderstorms as there will be 200-500 J/kg of MUCAPE available Sunday night with 40-50kts of shear. Severe storms cannot be ruled out Sunday with a potential low level jet across the Dakotas, but as of now it remains a very low risk. Monday some models have a small axis of 1000 J/kg of MUCAPE but others don't, so again low confidence in severe storms Monday, but not zero. Monday with the surface low in northern South Dakota cold air funnels or even a legit tornado could maybe be possible but it would be a very conditional risk. Through these 3 period there are medium to high chances of at least 1 inch of rain.

The rest of the week zonal flow takes over the northern CONUS, keeping temperatures seasonal in the mid 60s. Afternoon humidity values will lower back under 50 percent. Overnight lows will hang around the mid 40s and possibly upper 30s in the far north. Looking towards next weekend another shortwave could move in, lowering highs into the 50s with a chance of rain.

AVIATION /18Z TAFS THROUGH 18Z SUNDAY/

Issued at 1245 PM CDT Sat Sep 26 2026

Patchy IFR east to VFR west. A cold front is currently moving east through the state, clearing out the MVFR CIGs and turning winds to the west. This trend will continue west to east through the period, becoming mostly SKC overnight. The breezy west winds will mostly calm overnight as well.

BIS WATCHES/WARNINGS/ADVISORIES

None.