textproduct: Bismarck

KEY MESSAGES

- Rain today, tapering off from northwest to southeast this afternoon through tonight, but continuing in the James River Valley into Tuesday.

- Medium to high chances for at least 1 inch of rain along and south of Highway 200, and for at least 2 inches of rain in the southern James River Valley.

- Windy today into Tuesday, strongest across the far southwest and south central.

- Near to above average temperatures and drier weather are favored later in the week.

UPDATE

Issued at 600 AM CST Mon Nov 2 2026

The forecast remains in good shape. Widespread rain will continue through the morning. Patchy dense fog remains possible in areas that have light winds and simultaneous breaks in rainfall, but this should become increasingly uncommon through sunrise.

DISCUSSION

Issued at 358 AM CST Mon Nov 2 2026

A deep upper level trough is crossing the Northern and Central Rockies early this morning, with a series of lee surface cyclones developing from southeast Montana to northeast Colorado. The southern most surface low will become the dominant feature and quickly move northeast into eastern South Dakota by this afternoon. Intense synoptic scale lift will produce widespread rain across the state this morning, tapering off from northwest to southeast this afternoon through tonight. However, there is an emerging solution supported by recent initializations of the HRRR, RAP, REFS, and even the NBM to some extent that stall the low over southwest Minnesota through Tuesday, which would keep persistent rainfall over the James River Valley. Probability-matched mean rainfall from high- resolution ensembles is consistent with NBM calibrated QPF, which places at least 1 inch of rain from south central North Dakota to the James River Valley, and also in west central North Dakota, mainly over the Badlands. There are also medium to high chances for exceeding 2 inches of rain along and east of a line from around Linton to Carrington. Despite a lack of buoyancy, poor mid level lapse rates, and some uncertainty on the strength and location of low to mid level frontogenesis, other ensemble tools, such as the ECMWF EFI QPF and NAEFS precipitable water exceeding the climatological maximum values, lend further confidence to rain amounts this high. This is especially true if rain continues over the James River Valley through Tuesday, which could result in some locations receiving over 3 inches of rain. The lowest rain amounts are forecast along the Canadian border, where there are still medium chances for exceeding half an inch of rain.

The tightening of the surface pressure gradient will induce windy conditions today, lasting into Tuesday across southern and moreso eastern North Dakota. Model soundings continue to show very poor momentum transfer, but that could be overcome by the strong dynamics of the system. Confidence in a longer duration of sustained winds around 30 mph is high enough for a Wind Advisory in areas south of I-94 and west of the Missouri River, which is in effect from mid morning through late evening today. An advisory may be needed east of the river on Tuesday if the system does stall over southwest Minnesota, but model soundings continue to show very poor mixing potential.

Expect near-steady or slowly falling temperatures through this afternoon, with mid 40s northwest to mid 50s south central and east. The low temperature forecast for tonight and high temperature forecast for Tuesday are highly dependent on the progression of the low and associated cloud cover. Forecast lows below freezing in western North Dakota tonight are likely only achievable if clouds begin to clear before sunrise Tuesday morning. Forecast highs on Tuesday are in the mid to upper 40s, but these could end up cooler if the slower progression scenario verifies not only due to persistent cloud cover, but also due to stronger cold air advection.

Ensembles favor a pseudo omega blocking pattern over broad surface high pressure Wednesday and Thursday that could transition to a progressive northwest flow pattern to end the week. 3 out of 4 global ensemble clusters do pick up on a more potent shortwave digging down from Canada on Saturday in the form of an Alberta clipper. The NBM maintains near to above normal temperatures from the middle of the week through the weekend, with highs in the 40s and 50s and lows in the 20s and 30s.

AVIATION /12Z TAFS THROUGH 12Z TUESDAY/

Issued at 600 AM CST Mon Nov 2 2026

Widespread rain with MVFR to IFR visibility and IFR to LIFR ceilings will prevail today. The rain is forecast to taper off from northwest to southeast this afternoon and evening, but will continue at KJMS through the night. Ceilings could lift to MVFR after rain ends. Winds will become northeast to north and increase to 20-25 kts through this afternoon, with gusts to 30-35 kts.

BIS WATCHES/WARNINGS/ADVISORIES

Wind Advisory from 10 AM CST /9 AM MST/ this morning to midnight CST /11 PM MST/ tonight for NDZ040>044-061-062.