textproduct: Bismarck

KEY MESSAGES

- Much cooler this weekend, before slowly warming next week.

- High chances (60-90%) for rain Sunday night through Monday.

- Windy weekend, continuing into early next week.

DISCUSSION

Issued at 125 PM CDT Fri Sep 11 2026

The Northern Plains are mostly dominated by zonal flow, with a small shortwave embedded over Montana currently. A large upper level low system sits near Vancouver. At the surface the previous cold front has now made it all the way through North Dakota, so temperatures across western and central North Dakota are only in the mid 60s to lower 70s. A surface low pressure sits in east central South Dakota, with a pressure gradient affecting the eastern half of North Dakota, where winds are gusting around 20 mph. That upper level shortwave has created a narrow band of rain showers laid across eastern Montana, on an eastern track. The NBM has very little PoPs for these showers in North Dakota, so we had to manually add those in. These showers should track across northern North Dakota and slowly dissipate this evening.

As this zonal flow continues into the weekend, the below normal cooler temperatures will too. Tonight expect lows in the 40s again, then highs Saturday in the low to mid 60s. This trend will continue for Sunday as well. Saturday will be windy across the eastern half of the state as the surface low slides into western Minnesota, producing a strong pressure gradient across North Dakota. Northwest winds 15 to 30 mph are forecast.

Heading into Sunday and Monday that upper level low will slide into Montana, creating strong southwest flow over the Northern Rockies. This will create a surface low pressure that moves into the Dakotas, producing widespread rain Sunday night through Monday. With this surface pressure, another strong pressure gradient will occur. Sunday winds will be the strongest across the southwest where southeast winds 25 to 40 mph are forecast. Monday will be slightly windier with a frontal passage. Current NBM forecast winds across the west are 30 to 50mph, lower east. We will keep an eye on this for a possible Wind Advisory or Warning. The backside of this system will allow slightly warmer 850mb temperatures to come back north, warming our temperatures back into the mid 70s by the end of next week along with low chances for rain.

AVIATION /18Z TAFS THROUGH 18Z SATURDAY/

Issued at 1250 PM CDT Fri Sep 11 2026

VFR through the period with possible MVFR in the northwest this afternoon. There is also light rain showers possible across the northwest but confidence is low. Winds today will be northwesterly 10 to 20kts, increasing in the north and east Saturday to 15 to 30kts.

BIS WATCHES/WARNINGS/ADVISORIES

None.