textproduct: Bismarck

KEY MESSAGES

- Dangerously cold wind chills across the northern half of the state through Sunday morning, especially in the northwest this morning where wind chills could fall as low as 45 below zero. - Well below average temperatures are expected today and Saturday, with highs in the single digits above and below zero and lows in the teens and 20s below zero.

- Another round of accumulating snow will impact areas mainly south and west of Lake Sakakawea and the Missouri River this afternoon through Saturday morning.

- Temperatures are expected to moderate back to near or perhaps above normal next week.

UPDATE

Issued at 907 AM CST Fri Dec 12 2025

No major changes to the forecast with this update. Surface high pressure continues to push in from the southern Canadian Prairies, with colder air filtering in and breezy winds dropping apparent temperatures into the -30 to -40 range across the northern half of the state. Although the main shortwave is still off to our west, as previously discussed, we continue to see light radar returns resulting in light snow and decreased visibilities across far southwest North Dakota, corroborated by NDDOT travel cameras. We are not expecting much accumulation during the day today but will continue to monitor in case we need to move up the start time of the Winter Weather Advisory that goes into effect in this area this evening. Headlines continue as planned, with the Extreme Cold Warning and the southern extent of the Cold Weather Advisory set to expire at noon CST.

UPDATE Issued at 615 AM CST Fri Dec 12 2025

Visibilities have improved across central ND and the winter weather advisory was allowed to expire at 6 AM.

Although the main shortwave tracking across southwest ND will be tonight, this area is currently within an area of channeled vorticity and expect light snow and/or flurries this morning and possibly through much of the day. Accumulations will be light with maybe a half inch or so of accumulation possible through the day. Added a broad brush chance of light snow through the morning hours as a start and will pass this along to the day shift.

No changes are anticipated with the current cold weather headlines. As of 6 AM CST wind chills were as low as 38 below at sites in Burke and Mountrail counties in northwest ND, with plenty of time to drop into warning criteria. Wind chills were generally in the 28 to 36 below range in the Cold Weather Advisory.

Updated text products will be transmitted shortly.

DISCUSSION

Issued at 228 AM CST Fri Dec 12 2025

Currently, light snow along the Arctic cold front is exiting the southern James River Valley, with Arctic high pressure forecast to build over the area today. Strong pressure rises are expected to propagate eastward over the forecast area through around 12 UTC, before abating during the morning hours as the center of the Arctic High tracks over us. Blowing and drifting snow currently covered with a Winter Weather Advisory through 6 AM CST. Visibilities over eastern portions of central ND are currently in the 3-5SM range. Will continue to monitor and we may be able to cancel early, if not expect it will not need to be extended yet again. Current wind chills are generally in the 30-35 below range over northwest ND and 25 to 30 below in the north central, but wind chills are expected to continue drop through mid morning as the Arctic high builds over the area. No changes to the current Extreme Cold Warning or Cold Weather Advisory are anticipated at this time.

For today, winds will slowly diminish through the morning hours. The Extreme Cold Warning in the northwest, and the Cold Weather Advisory right along the south side of Lake Sakakawea are forecast to end at noon. Then this afternoon through Saturday morning we will be under a Cold Weather Advisory over northwest and north central ND, and into the northern James River Valley.

In addition to the continuing dangerously cold wind chills, we will see another round of snow clipping western and south central North Dakota generally tonight through Saturday morning, but there will likely be a little light snow beginning in the southwest this afternoon.

A shortwave trough propagating through the mean northwest upper flow situated across the Northern Plains will track across southwest ND tonight into Saturday morning. This will bring a swath of light snow to western and south central ND. For the most part this looks to be mainly light snow. However, there looks to be enough synoptic scale forcing clipping the southwest portion of the state tonight to squeeze out some decent qpf amounts. In addition, there is some decent 70H FG forcing traversing this area tonight as well. As you go down to 850 MB the FG forcing drops off quite a bit. Forecast soundings indicate this quite well with the strongest omega situated within the 70H-60H pressure level. With this setup, we could see a general band of heavier snow set up over far southwest ND. We would also like to see some steep lapse rates (generally above 6 deg C/KM) in order to get some significant banding. We just don't quite make it, with the steepest lapse rates remaining south and west of the far southwest portion of the state. The developmental NBM 24 hour probability of 2 or more inches of snow, is showing high probabilities (greater the 70 percent) over far southwest ND. This includes Bowman, most of Slope and Adams counties, and a small portion of southern Golden Valley County. Medium probabilities (40-70 percent) include portions of Billings, Stark and Hettinger counties. Probabilities of 4 or more inches is only in the moderate category for portions of Bowman and Slope counties. Although the forcing is situated more towards the top of the saturated profile, almost the entire profile from the surface to 600MB is within the dendritic growth zone. This would support high snow ratios, in excess of 20 to 1. portions of over far southwest ND.

In coordination with our neighbors to the south and west, we will issue a Winter Weather Advisory for Snow over southwest North Dakota. The greatest potential for advisory criteria snow amounts look to remain in the far southwest. However, with the potential for some higher SLR values, will be a little generous with our advisory and include all of the southwest (Golden Valley, Billings, Stark, Slope, Bowman, Hettinger and Adams Counties. In general, we expect snow amounts of 2-5 inches in the advisory area, with the highest amounts over far southwest ND. With the high SLR's some reports of around 6 inches of light fluffy snow would not be surprising.

Winds are expected to be generally light with this system (around 10 mph or less) so blowing and drifting snow impacts are expected to be minimal. We do see winds pick up from the south Saturday night into Sunday, so this timeframe may be something to monitor for impacts due to blowing and drifting snow.

Our current Cold Weather highlights go into Saturday, but we may need to extend these into Sunday morning for at least a portion of the northern and eastern forecast area. The trend has actually been towards a quicker warmup Sunday than initially thought. Initially very cold temperatures Saturday evening look to warm through the night, especially west, but also into central ND. Already by Sunday afternoon current NBM ensemble forecast highs approach 40 degrees in the southwest. With a bunch of snow falling there tonight into Saturday morning, it might be a little hard to achieve those highs. We'll see. The warmup continues into early next week with widespread 40 degree readings forecast by Tuesday. Then we trend back towards reality by mid-week.

After the snow southwest tonight into Saturday morning, we are forecast to remain dry through the day Tuesday. Then we start to see another round of clippers tracking through a quasi-zonal upper level flow. With our warm temperatures expected next week, any precipitation would probably be a mix.

AVIATION /12Z TAFS THROUGH 12Z SATURDAY/

Issued at 557 AM CST Fri Dec 12 2025

Strong winds were creating some patchy blowing snow that were impacting the XWA, MOT and JMS TAF sites to begin the 12Z TAF period. Expect visibilities in blowing snow at these sites to improve to VFR by around mid morning or so. Periods of light snow or flurries will continue over southwest ND through much of the day today with possibly some MVFR visibilities at times but expect mostly VFR visibilities and ceilings, including KDIK. Lake effect snow showers are impacting the Hazen area downstream of Lake Sakakawea, with IFR ceilings and visibilities in snow and probably some blowing snow due to the strong winds. This activity may reach the Bismarck/Mandan area, including possible MVFR ceilings at KBIS.

Otherwise, expect strong northwest winds to gradually decrease through the day, and then becoming light by tonight. Another round of snow will impact southwest North Dakota tonight into early Saturday morning. Expect MVFR to IFR ceilings and visibilities across much of southwest ND late this evening through tonight, including at KDIK. Elsewhere, a stray MVFR ceiling can not be ruled out within the Arctic airmass, but generally VFR conditions are expected.

BIS WATCHES/WARNINGS/ADVISORIES

Extreme Cold Warning until noon CST today for NDZ001-002-009- 010. Cold Weather Advisory until noon CST Saturday for NDZ001-002- 009-010. Cold Weather Advisory until noon CST Saturday for NDZ003>005- 011>013-021>023-025-036-037. Cold Weather Advisory until noon CST /11 AM MST/ today for NDZ017>020-035. Winter Weather Advisory from 5 PM this afternoon to 8 AM MST Saturday for NDZ031>033-040-041-043-044.