textproduct: Bismarck

KEY MESSAGES

- There is a 20 to 40 percent chance for light freezing rain (mixed with snow in the Turtle Mountains) along and north of a line from Crosby to Minot to Jamestown late tonight into Tuesday morning. - Warmer on Tuesday, then a large spread in temperatures from northeast (colder) to southwest (warmer) mid to late week.

- Low to medium chances for snow mainly across central and eastern North Dakota Tuesday night into Wednesday.

UPDATE

Issued at 1130 PM CST Mon Dec 29 2025

An area of weak to moderate radar reflectivities is moving out of the southern Canadian Praries into portions of northwest and north central North Dakota at the time of this mid night update. While obs upstram have been reporting light snowfall associated with these reflectivies, an interrogation of BUFKIT model soundings reveals a shallow 950 to 850mb warm nose as WAA continues across the forecast area. With this, and with sub freezing surface air temperatures, any precpitation that does reach the ground is expected to do so as freezing rain. Though QPF amounts appear to be somewhat limited, a glaze of ice is possible across the north, especially in the Turtle Mountains area. We will continue to monitor conditions through the night. No major adjustments to the forecast were performed at this time, as it broadly remains on track.

UPDATE Issued at 1021 PM CST Mon Dec 29 2025

So far, the only suspected precipitation in central North Dakota this evening was from a small area of what was likely light snow from between Steele and Jamestown down towards Ellendale. We could not confirm the presence of snow, however, as it moved over an observation-sparse area. But associated radar reflectivity did exceed 30 dBZ.

A larger area of radar reflectivity can now be seen moving closer to the Canadian border. The 00Z suite of CAMs shows slightly better agreement on a most likely solution of light freezing rain falling along and north of Highway 52 late tonight into early Tuesday morning, with snow and perhaps sleet mixed with the freezing rain initially in the Turtle Mountains area. The overall trends from earlier forecasts are 1) slightly higher confidence in the occurrence of freezing rain; 2) a slight northeastward shift in the highest probabilities for accumulating ice; and 3) an eastward shift in the snow-freezing rain transition zone. We have therefore reissued a Special Weather Statement for all but a few southern counties that were highlighted in one earlier today, and shifted its focus more on the freezing rain threat as opposed to a mix.

UPDATE Issued at 621 PM CST Mon Dec 29 2025

The near-term forecast remains on track. There has not been any evidence of precipitation reaching the ground from the radar reflectivity over the Turtle Mountains and Devils Lake Basin. Made some minor timing and spatial adjustments to PoPs through tonight based on latest rapid refresh guidance, and otherwise blended in current conditions and trends for this update.

DISCUSSION

Issued at 253 PM CST Mon Dec 29 2025

This afternoon, a closed low was analyzed over the Great Lakes region, with the attendant trough digging into the Midwest and upstream cyclonic flow aloft across the Northern Plains. At the surface, high pressure extended over southern South Dakota and the central Plains, with a low centered in northern Saskatchewan. A warm front extended south of the surface low through western North Dakota, with a shift to more westerly winds behind the front. Some widespread mid-level clouds continue on the cool side of the front, with afternoon highs ranging from the teens in our eastern counties to around freezing in southwest North Dakota.

A big forecast question with this update is precipitation chances and type with a few impulses moving through the mean northwest flow this evening, overnight, and into Tuesday morning. As the warm front continues pushing east, high-res guidance wants to produce light snow in north central North Dakota and the James River Valley, so we do have some low POPs to account for this later this evening. As the surface low then tracks southeast through the southern Canadian Prairies, another impulse and boundary drops south and a swath of light precipitation is projected to move north to south through much of the forecast area late tonight into Tuesday morning. With this wave, there has been a modest increase in a freezing rain signal, with forecast soundings showing a few hours of enough of a warm nose to melt hydrometeors with sub-freezing surface air temperatures. Although QPF amounts look very light, we have seen multiple times already this winter that it takes very little freezing rain to lead to surface impacts. We have increased messaging for this potential, and are highlighting the northwest into much of central North Dakota for a low chance of a glaze of ice. This could potentially impact the Tuesday morning commute. There could also be a dusting of snow in the Turtle Mountains area. We have issued a Special Weather Statement to cover the wintry mix potential.

As this weak system moves out on Tuesday, we get a brief reprieve and warmup, with forecast highs in the 30s. A clipper system then quickly slides along a baroclinic zone that gets established across the state, introducing chances for snow late Tuesday night into Wednesday. Snow chances are primarily limited to north central and eastern North Dakota, with relatively good agreement on this being a light snow event of 1 to 2 inches, as internal probabilities based on the gridded forecast give a 10 percent chance of exceeding 3 inches of snow. However, as the previous shift noted, there is enough of a signal for at least moderate frontogenesis and lapse rates that we can't rule out some banded snowfall, which gets washed out in blended probabilities.

Wednesday through the remainder of the week, we are expecting a large range in temperatures from northeast to southwest, with highs mainly in the teens in the far north central and east, to the 30s southwest. With persistent cyclonic flow aloft favored, we would not be surprised for some additional light precipitation events during this period, but predictability at this juncture is quite low. Uncertainty in the overall pattern increase late in the weekend into next week, when NBM 25th/75th temperature percentiles have quite a large spread due to ensemble members being split on how the synoptic flow progresses.

AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/

Issued at 1130 AM CST Mon Dec 29 2025

VFR conditions are found at all terminals to begin the 06Z TAF period. An area of freezing rain is expected to move out of Canadian and into parts of northwest and central North Dakota through Tuesday morning. With this update, have added a PROB30 for light FZRA at KMOT. Otherwise, confidence is not high enough to mention this in the KXWA, KBIS, or KJMS TAFs at this time. By Tuesday afternoon, MVFR ceilings are forecast to develop from KMOT to KJMS. There is a low chance this could extend farther to the west, but it could also end up being a VFR ceiling or a scattered MVFR deck across western and south central North Dakota. Westerly winds will increase to around 10-15 kts through tonight, then turn to the northwest and become gusty on Tuesday. A period of low level wind shear is expected across northwest and central North Dakota Tuesday morning.

BIS WATCHES/WARNINGS/ADVISORIES

None.