textproduct: Bismarck

KEY MESSAGES

- Warmer temperatures, breezy conditions, and low to medium (10 to 40 percent) chances for light snow showers on Tuesday.

- An active weather pattern is forecast for the rest of this week, resulting in periodic low to medium chances for snow, breezy conditions, and moderate to large fluctuations in day- to-day temperatures.

- Very cold temperatures are forecast Wednesday night into Thursday morning, with wind chills possibly as low as 30 below zero.

UPDATE

Issued at 1018 PM CST Mon Dec 1 2025

Overall, the forecast for the short term period remains on track. Lake effect clouds streaming off of Lakes Sakakawea and Audubon are now being stretched eastward, and there will soon no longer be cold enough temperatures aloft to support this feature as warmer air advection commences. 00Z guidance has not offered any increased confidence in precipitation outcomes (timing, location, coverage, etc.) for the clipper system on Tuesday. One thing that has shown up in the RAP though is the potential for a period of light freezing rain or freezing drizzle due to a loss of ice nucleation. The pocket of mid level drier air is forecast to move from northwest to southeast across the state during the daytime hours. Confidence remains low in any precipitation actually occurring under the drier air aloft, even though there could be a deep enough low level saturated layer with modest lift. If light freezing rain or freezing drizzle were to occur, the most likely timing and location appears to be from Williams and McKenzie Counties to Lake Sakakawea during the mid to late morning hours, but it is still only a 15 percent chance at most. During the afternoon, surface temperatures are forecast to rise near or above freezing, resulting in rain if there is any precipitation associated with no ice crystal production aloft.

UPDATE Issued at 628 PM CST Mon Dec 1 2025

High-resolution models show fog, likely in the form of tiny ice crystals, developing across central North Dakota later this evening and migrating eastward through the night. Light surface winds, a mostly clear sky aside from lake effect clouds, and forecast soundings support this potential. The fog is not expected to be dense should it develop. A mention of patchy fog has been added to the forecast to account for this. Most other changes for this update were to blend in current observations and trends. Did convert the low chances for lake effect snow to flurries as there as been no recent ground-truth verification of any snowfall under the clouds streaming off of Lake Sakakawea.

DISCUSSION

Issued at 302 PM CST Mon Dec 1 2025

Cold temperatures will continue through this evening into the start of the overnight hours. Lake effect snow showers south and east of Lake Sakakawea will also be found into the early evening hours, diminishing later this evening or early overnight. Warming westerly flow aloft with a warm return southerly flow at the surface will start warming temperatures late tonight. Forecast lows tonight will generally be near zero to around 10 degrees, although may occur earlier in the overnight hours. Warming temperatures then look to be found on Tuesday, with highs currently forecast in the mid 20s to mid 30s. NBM produced even warmer temps than currently published, however lowered these to the NBM50th percentile given abundant snow depth across the area. Upper level wave and clipper system will move through the state Tuesday as well. This could still bring snow showers, although confidence in pops is low to medium as current hi-res data not showing a lot of organized snow showers. Tuesday morning may have the more increased chances for pops with better synoptic forcing and some frontogenesis potential. However, current models hinting the upper wave may outrun the surface features, making organize snow isolated to scattered. NBM currently has 10 to 40% chances for accumulating snow across the CWA with the higher chances coming in the southwest. Chances for at least an inch are around 10 percent or less. The front and wave still look potent thus placed in widespread slight chance for snow at this time. Later in the day Tuesday through Tuesday night, cold front moves through bringing low clouds and perhaps some light snow. There could be a small window freezing rain or freezing drizzle is possible during this time period, if the mid layers dry out quicker. Breezy winds could also bring some patchy blowing snow on Tuesday through Tuesday night. Behind the mentioned front cold temperatures move in Tuesday night into Wednesday morning, with lows forecast up to 10 degrees below zero. Some isolated dangerous winds chills are possible. Dry and cold conditions look to be found on Wednesday, with highs in the single digits to teens. Breezy northwest winds may also linger. Some isolated lake effect snow showers may again be possible near Lake Sakakawea. Below zero temperatures return Wednesday night into Thursday morning. If steady northwest winds linger through the night, then perhaps some near Cold Weather Advisory wind chills are possible, mainly in the southeast.

A series of weak waves in northwest flow may then push through to end the week Thursday and Friday. Each bringing low (around 20%) chances of snow. Slightly warmer temperatures will accompany these waves, with highs in the 20s to lower 30s and lows in the single digits to teens. Perhaps some breezy winds also return with these disturbances. Better chances for snow then look to return Friday night through Saturday night. A similar wave as this past weekend is starting to show up in the clusters, indicating more accumulating snow is possible. Chances for at least 2 inches of snow in a 24 hour period to start the weekend are around 20 to 50 percent. These chances lower yet remain 10 to 20 percent later in the weekend. High accumulations will depend on where a surface front sets up and the location of the surface low. Current temperature forecast through the weekend remain near to below normal, depending on where the front sets up. This uncertainty in front location likely is the reason for large spreads in NBM temperatures. Overall those with travel plans this weekend will want to keep up to date on the latest forecast.

AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/

Issued at 1018 PM CST Mon Dec 1 2025

All terminals begin the 00Z TAF cycle with VFR conditions. Areas from around KBIS to KJMS could see low clouds or fog in the form of ice crystals develop later this evening through tonight. Forecast confidence in this happening, and its coverage if it does develop, is not high enough to mention in the TAFs at this time. MVFR ceilings are forecast to develop from west to east during the day Tuesday. There will also be low chances for light snow at times, but there is too much uncertainty on timing, location, and coverage of snow to mention in the TAFs at this time. Light west to southwest winds through tonight will become west to northwest on Tuesday at around 15 kts, with some 25-30 kt gusts possible in the afternoon.

BIS WATCHES/WARNINGS/ADVISORIES

None.