textproduct: Bismarck

KEY MESSAGES

- Freezing rain will impact most of western and central North Dakota this morning, with ice accumulations as high as one to two tenths of an inch.

- Very strong winds expected late this morning through tonight, with gusts as high as 65 mph.

- 1 to 4 inches of snow are expected in the Turtle Mountains area this morning through tonight.

- Another round of snow will impact all of western and central North Dakota Wednesday afternoon through Thursday night.

- Below average temperatures are expected Wednesday through the upcoming weekend, with dangerous wind chills possible Thursday evening through Saturday morning.

UPDATE

Issued at 645 AM CST Tue Dec 9 2025

Precipitation has developed across much of western and central North Dakota this morning. Across the west, air temperatures have broadly climbed back above freezing. That being said, surface temperatures across much of the northwest and portions of the southwest remain around or below freezing, and thus ice accumulation is still being reported. Across central North Dakota, air temperatures and surface temperatures both remain around or slightly below freezing this morning, thus much if not all precipitation reaching the ground at this time is expected to be freezing rain. In the far northwest, where precipitation has transitioned to rain, and where precpitation has started to end, from 0.10" to 0.20" was reported. Elsewhere, around 0.05" has fallen so far. With this update, have blended in some of the latest short- term models in the PoPs, though these changes have been relatively minor. Otherwise, the forecast remains on track at this time.

DISCUSSION

Issued at 445 AM CST Tue Dec 9 2025

Cyclonic flow continues over the northern Plains today as a stubborn Hudson Bay Low lingers to the northeast. We've had a parade of clipper systems pass through western and central North Dakota over the past week, with a surface low associated with one yesterday having lingered to the east of the forecast area. Overnight, low stratus wrapping around this low slowly moved eastward across central and eastern North Dakota. With the warm air temperatures over the fresh snow pack, patchy to areas of fog had developed on the back edge of this stratus deck, occasionally dropping visibilities as low as 1/4M, though these were fairly brief limited. Mid to high level clouds have since overrun this fog through the moving, and relaxing the near surface inversion and allowing this fog to dissipate. Low temperatures this morning are from the lower single digits from the mid teens to mid 20s central, to the upper 20s and 30s west. Have temperatures this afternoon remain above normal for this time of year, from the lower to mid 30s north central to the mid 40s southwest,

Now onto the main event for today. A robust upper level shortwave is passing through the northern Plains this morning, accompanied by an strong attendant low pressure system that is expected to cut from northeastern through southwestern North Dakota today through early Wednesday. This system, and the development of a 60-70 knots 850mb jet across the forecast area this afternoon, will produced a variety of winter weather and wind related impacts this morning through late tonight. We will tackle each hazard in turn below.

Freezing rain:

- Widespread precipitation is expected across western and central North Dakota as initial push of 850 mb warm air advection pass from west to east this morning. With this ongoing WAA, a significant warm nose of +6-8 deg can be found. In the southwest, where antecedent mid to high level clouds have lingered through much of the night, and where the attendant warm front associated with the low pressure is expected to move across fairly quickly, air temperatures are broadly expected to be well above freezing when precipitation begins. That being said, surface temperatures themselves may be hovering around freezing, and thus it isn't out of the cards for a brief shot at freezing rain this morning, though the warm air temperatures and warm subsurface temperatures will likely keep this period short. With this, a light glaze of ice is possible in southwestern North Dakota this morning, though the warm air and subsurface temperatures as well as the liquid precipitation will help melt this fairly quickly. In the northwest and central, air temperatures around or sub freezing are anticipated at the onset precipitation, and thus freezing rain is expected though much of the coming morning. A general transition from freezing rain to snow is expected through the mid to late morning as the column continues saturate along and behind the aforementioned warm front, along with a trailing slug of 850mb CAA eroding the warm nose. For the northwest and south central, including the southern James River Valley, a general transition from freezing rain to rain is anticipated by the mid morning hours as air temperatures rise above freezing. When it's all said and, this area is expected to see 0.01" to 0.10" of ice accumulation, with some isolated pockets approaching 0.20", through this period. Impacts due to freezing rain may linger for a few hours after the transition to rain as surface temperatures somewhat lag behind, though the warm air and and liquid precpitation should help melt the ice by the late morning/early afternoon. The north central is a slightly different story, especially in an area from the Turtle Mountains down through the northern James River Valley. Here, a general transition from freezing rain to snow is expected as a second slug of CAA moving out of the southern Canadian Prairies erodes the warm nose aloft through the late morning. The longer residence time of the freezing rain and a slightly juicer precipitation environment will push expected ice accumulations up to 0.10" to 0.20", with pockets of locally high amounts approaching 0.25" possible. Notably, the warm front will struggle to reach this area before moving to the southeast with the inciting low pressure system, and thus is not anticipated to experience much melting before a cold front also attendant to the system drops out of the north. The higher end of all these ranges are assuming a much slower transition to either rain or snow through this morning.

Wind:

- Wind is expected to be the most widespread and impactful hazard associated with this system. A 60-70knot 850mb jet is expected to develop across western and south central North Dakota this afternoon, somewhat displaced underneath a very strong 120+knot jet further to the southwest in southeastern Montana and western South Dakota. Strong pressure rises and an initial slug of CAA aloft is anticipated to allow much of these winds to mix down initially in the southwest late this morning, them more broadly across portions of western and central North Dakota this afternoon as a much more robust push of CAA moves out of the north. Model sounding have been somewhat reticent to fully mix the boundary layer this afternoon, though for the reasons mentioned above, we still anticipated very strong wind gusts up to 60 to 65 MPH across portions of wester and central North Dakota this afternoon. These strongest wind gusts may not reach as far north and east as the Turtle Mountain region as the 850mb jet remains somewhat displaced further to the southwest, though gusts up to 50 MPH should still be anticipated this afternoon.

Snow:

- Not much has changed regarding our expectations for snow. Once the precipitation in the north central into the northern James River Valley transitions from freezing rain early this afternoon, broadly 1 to 4 inches of accumulation are expected through late tonight. Weak mid level FG forcing across portions of northeastern North Dakota could cause some periods of slightly heavier snowfall across this area. With the strong winds anticipated today, we must consider the potential for blowing snow. With liquid precipitation expected through much of the morning today, and with the warmer air temperatures we experienced yesterday, though thought is that much of existing snowpack is going to be unable to blow very much. If anything, drifting snow and slush would be the general expectation. That being said, where falling snow meets the strong winds gusts this afternoon and evening, periods of poor visibility are possible.

Now regarding products. A Winter Weather Advisory is in effect everywhere except far southwestern North Dakota this morning through 12 PM CST, mainly to account for the freezing rain potential, then across portions of north central North Dakota, including the northern James River Valley, though late tonight due to lingering ice accumulation, snowfall, and the potential for blowing snow. A High Wind Warning will be in effect across the far southwest from 9 AM this morning through 12 PM CST this afternoon, then across most of western and central North Dakota, except the Turtle Mountains region, through late tonight.

Both wind and precipitation is anticipated to diminish through late Tuesday night, early Wednesday morning as the inciting low pressure system moves off to the southwest. With a much cooler airmass now draping across the northern Plains, lows on Wednesday drop into the single digits below north, to the upper single digits to mid teens south. Afternoon highs on Wednesday are only from the upper single digits north central, to the lower to mid 30s southwest. Another weak shortwave and attendant low pressure system is progged to pass across North Dakota Wednesday afternoon through the day, with medium to high chances (40 to 70s percent) for precipitation through this period. While much of this is expected to fall as lightly accumulating snowfall, another period of freezing rain is possible Wednesday night through Thursday morning in the far southwest as modest WAA wraps around into the 850mb layer, then transitioning to snow by Thursday afternoon. The calibrated NBM 5.0 advertises medium chances (40 to 60 percent) for snow accumulations greater than an inch across the west, with low chances (10 to 30 percent) central through Friday morning, and a low to medium chances (10 to 30 percent) for a glaze of ice in the far southwest through Thursday afternoon.

Looking ahead to this weekend, a reinforcing push of arctic air is anticipated to drop out of the northern Plains early Friday, cooling temperatures even further. High temperatures Friday and Saturday are broadly from the upper single digits below to the lower single digits above, with much of the forecast area not expected to rise above freezing either day. With morning low temperatures on Friday, Saturday, and Sunday broadly expected to been from the -20 to -10, dangerously cold conditions are possible this weekend. Much of northwestern and central North Dakota has medium to high chances (40 to 70 percent) for wind chills to drop to or below -30 during this period.

AVIATION /12Z TAFS THROUGH 12Z WEDNESDAY/

Issued at 645 AM CST Tue Dec 9 2025

High impact weather is found across North Dakota today. This morning, MVFR to LIFR ceilings are found as precipitation spreads across much of the forecast area, falling mainly as freezing rain in the northwest and central. A general transition from freezing rain to normal rain is expected for the northwest and south central through the mid morning, then a general transition to snow across the north central by the late morning, early afternoon. Rain and snow will then exit through the afternoon and evening, with cloud cover lifting through the same period. Ice accumulations broadly from one hundreth to a tenth of an inch are possible across northwestern and south central North Dakota, and up to two tenths of an inch in north central North DAkota. Snow accumulation from 1 to 4 inches is possible in the Turtle Mountains regions, with a trace to an inch also possible elsewhere in central North Dakota. With this update, have added precpitation and MVFR ceilings to all terminals this morning through the afternoon, with precpitation possibly lingering at KMOT through the early evening. Also today, strong low level jet will develop across western and central North Dakota through the late morning and afternoon. With this, LLWS is present at KXWA, KDIK, and KBIS this morning through the late afternoon. Confidence in LLWS is lower at KMOT and KJMS at this time, though is still possible. Very strong west to northwest winds will also mix down to the surface across western, south central, and portions of north central North Dakota this morning through this evening, with speeds up to 45 MPH and gust up to 65 MPH expected. Winds will generally start to diminish overnight, though will remain moderately strong through early to mid Wednesday morning.

BIS WATCHES/WARNINGS/ADVISORIES

Winter Weather Advisory until noon CST /11 AM MST/ today for NDZ001>003-009>012-017>023-025-033>037-041-042-044>048-050-051. High Wind Warning from noon CST /11 AM MST/ today to 9 PM CST /8 PM MST/ this evening for NDZ001>003-009>012-017>021. Winter Weather Advisory until midnight CST tonight for NDZ004- 005-013. High Wind Warning from noon CST /11 AM MST/ today to 3 AM CST /2 AM MST/ Wednesday for NDZ022-023-025-033>037-041-042- 044>048-050-051. High Wind Warning from 8 AM this morning to 8 PM MST this evening for NDZ031-032-040-043.