textproduct: Bismarck

KEY MESSAGES

- Medium to high chances for precipitation this evening into Monday morning, mainly south of Highway 2. Forecast precipitation amounts have lowered even more.

- Mainly dry conditions expected from Tuesday through the rest of the week.

- Below average temperatures continue through the first part of the week, then a warming trend develops.

UPDATE

Issued at 703 PM CDT Sun Apr 26 2026

The forecast for tonight remains mainly on track. Adjusted POPs a bit to delay the arrival of precipitation, though these changes were minor. Rain is rapidly developing and advancing north into southern areas of the state ahead of a northeastward moving embedded impulse, with another area of rain and snow along and north of a sfc trough from parts of eastern Montana into northwestern North Dakota. Will make adjustments to the forecast as needed this evening.

DISCUSSION

Issued at 220 PM CDT Sun Apr 26 2026

Currently the famous upper level low that hasn't moved much in the last few days, has actually shifted north. There is a trough extending off the center down to northern California, leading to southwest flow across most of the rest of the CONUS. At the surface the Colorado Low is just forming on the mountain, but widespread rain is already on going in the Central and Northern Plains in the southwest flow. In eastern Montana and far northwestern North Dakota scattered snow showers have been on going. Little to no accumulations are expected. The bulk of the rain showers are located in central and southern South Dakota, along and south in Interstate 90. Temperatures today are slightly warmer and near normal as the southwest flow has some warm air advection.

This evening the surface low will wrap up and move northeast, bringing the rain north into the state. It is expected to then continue raining through Monday morning in most of the state besides the far north. As in prior forecast runs, the NBM continues to move the bulk of the QPF east into Minnesota and we are now left with less than 0.50 inches in the entire CWA. The highest QPF amounts will likely be in far southeastern North Dakota where 1 inch could fall.

With the strong surface low exiting the Northern Plains Monday morning, there will a tight pressure gradient and a slight pressure bubble in southeast North Dakota... it will be windy. The James River Valley will be the bullseye where gusts up to 45 mph are possible from the north. We held off on a Wind Advisory on this shift but will likely be needing one. The NBM was blended with some NBM 90th to just slightly boost the winds with the drier, cooler air.

The rest of the week will be drier with multiple shortwave ridges, eventually leading to quasi-zonal flow possible late in the week. This in turn will lead to a slight warming trend where we could see temperatures return to near normal or above (60F) by Thursday.

AVIATION /00Z TAFS THROUGH 00Z TUESDAY/

Issued at 703 PM CDT Sun Apr 26 2026

Rain and lowering ceilings will move in from South Dakota and spread over southern terminals tonight, with MVFR to IFR ceilings expected. VFR conditions will prevail north (KXWA and KMOT). Conditions across the south will then trend VFR on Monday. Winds will transition to north-northeast this evening, and will become strong over central and eastern areas of North Dakota on Monday, especially east.

BIS WATCHES/WARNINGS/ADVISORIES

None.