textproduct: Bismarck

KEY MESSAGES

- Periods of light snow, areas of blowing snow, areas of freezing drizzle, and patchy dense fog will impact much of western and central North Dakota tonight.

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

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

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

UPDATE

Issued at 1146 PM CST Thu Dec 11 2025

The Arctic front is currently situated from northeast through south central ND, with strong northwest winds extending back into western ND. Currently the greatest impacts are along and ahead of the Arctic front, but areas of blowing snow are reducing visibilities in western ND as winds are gusting into the 25 to 35 mph range. The current advisory which was forecast to expire at midnight has been extended through 6 AM. This should allow enough time for any falling snow to exit the forecast area and allow the stronger winds with the Arctic front to subside a bit. Updated Advisory has already been sent. Will send remaining text products shortly.

UPDATE Issued at 1002 PM CST Thu Dec 11 2025

Much of the Winter Weather Advisory has once again been extended until midnight CST. An area of falling snow continues to advance eastward across the northern half of the state. Where snow is not falling, a variety of fog, freezing drizzle, and blowing snow continues to reduce visibility. Fog and freezing drizzle should no longer be a concern after midnight, and falling snow should be on its way out of our forecast area by then. Blowing snow could remain a concern through the night however, although perhaps not at advisory level criteria. One factor that has increased blowing snow impacts above our expectations is that we are seeing slightly stronger winds behind the front than we had anticipated. We blended some higher winds into the forecast through tonight as modest surface pressure rises and cold air advection through tightly packed isotherms are forecast to persist over the region. This in turn has resulted in a lower wind chill forecast for tonight, which had already been bordering on warning criteria of 40 below in the northwest. The 4 northwest counties have therefore been upgraded to an Extreme Cold Warning through tomorrow morning. Their Cold Weather Advisory will then resume tomorrow afternoon through Saturday morning. We have also added another tier of counties along most of the southern end of the Cold Weather Advisory just through tomorrow morning, including McKenzie, Dunn, Mercer, Oliver, and Burleigh.

UPDATE Issued at 644 PM CST Thu Dec 11 2025

A variety of nuisance impacts continue across much of western and central North Dakota this evening. Ahead of the Arctic cold front, which has now entered northwest North Dakota, areas of freezing drizzle and dense fog persist. With and trailing the frontal passage is a period of light to at times moderate snow with gusty winds as high as 40 mph, which is combining to reduce visibility as low as one mile. Given that a majority of our forecast area is experiencing at least one of the mentioned hazards, we have extended the Winter Weather Advisory until 9 PM CST and expanded it to the north and east. The advisory was not extended for the 4 southwest counties, as temperatures there are near to above freezing. It was also not expanded into LaMoure and Dickey Counties as there is lower confidence in impacts developing there.

DISCUSSION

Issued at 348 PM CST Thu Dec 11 2025

Two fronts will continue to bring some winter impacts through tonight. A stalled frontal boundary continues to bring light snow, with pockets of freezing drizzle south and west of the Missouri River this afternoon. Areas further away from this front continue to see patchy fog and freezing drizzle as well, which could linger into this evening. An arctic cold front will then push across the state tonight and bring the next best chance for light snow for most of the area. This front is also expected to clear out most of the fog and freezing drizzle that has lingered across the area today. Additional snow accumulations around an inch can be expected through tonight, with little new ice accumulations expected. Ongoing Winter Weather Advisories remain for lingering light snow and pockets of freezing drizzle through this evening. Behind this front will be breezy northwest winds. This could bring some areas of blowing snow, although the blow-ability of the snow remains uncertain. Thus have held off on any Winter Weather Advisories for blowing snow. There is high confidence that behind this arctic front will be very cold temperatures and wind chills. Have issued a Cold Weather Advisory to the highest confidence areas for this cold weather tonight, and given this cold air lingers, have issued this through Saturday morning. Look for lows in the single digits to teens below zero tonight, with wind chills to near 40 below zero. Surface high settles in for Friday, continuing cold temperatures and breezy winds across the central and east. Once again blowing snow could continue across much of the area, although confidence in Winter Weather Advisory impacts was low at this time. Arctic front stalls in the southwest which could bring chances for light snow in these areas.

Surface high will push through Friday night through Saturday, continuing more cold air across much of the state. Cold Weather Advisory remains during this time period, and some areas in the north may approach Extreme Cold Warning criteria of wind chills colder than 40 below zero. Meanwhile, the stalled arctic front in the southwest could continue snow Friday night into Saturday, with a Wyoming low sliding south along this front perhaps bringing some enhances snow rates at times. NBM chances for over 4 inches are currently up to 50% in these areas, with the experimental version of the NBM showing slightly higher chances. This could bring Winter Weather Advisory impacts, although confidence was not high enough to issue one at this time. Highs Saturday will struggle to get above zero for most areas. Surface high then moves through the Saturday night, this will likely be the coldest air temperatures of the weekend, although lighter winds may see similar wind chills to previous nights. Air temperature lows are forecast in the teens to 20s below zero, with much colder wind chills from there. As the high pulls away Sunday a breezy southerly flow could return across the area, which should warm temperatures for most areas, perhaps back to near normal for several sites, especially in the west. Mainly dry conditions also look to be found for Sunday.

Ridging with zonal flow is then forecast for at least the start of next week. This brings warming temperatures and limited chances for precipitation. NBM spreads for early next week even showing high confidence in these warming temperatures. Mid to late week could see a cool down, although NBM spreads are high. This depends on the ridge breaking down. If it does break down this could lead to the next active pattern for the state, although the confidence is low to moderate at this time with current NBM forecast showing a cooling forecast and chances for snow.

AVIATION /06Z TAFS THROUGH 06Z SATURDAY/

Issued at 1146 PM CST Thu Dec 11 2025

A cold front currently from northeast through south central ND, will continue to push east overnight. Ahead of this front, expect widespread IFR to LIFR ceilings, areas of freezing drizzle reducing visibility to MVFR/IFR levels, and patchy dense fog reducing visibility as low as VLIFR levels. The arrival of the front will bring a period of light to moderate snowfall to most locations and gusty northwest winds as high as 35 kts, which may also cause areas of blowing snow reducing visibility to MVFR/IFR levels. Northern parts of the state have higher probabilities compared to the south for visibility restrictions due to snow and blowing snow. Ceilings behind the front are forecast to initially improve to MVFR, and eventually VFR at most locations. An MVFR ceiling streaming southeast off of Lake Sakakawea is expected to persist through at least Friday morning, which may approach KBIS. Gusty northwest winds will continue through Friday afternoon. By Friday evening, another area of light snow with MVFR ceilings could begin approaching the southwest corner of the state.

BIS WATCHES/WARNINGS/ADVISORIES

Extreme Cold Warning until noon CST Friday for NDZ001-002-009- 010. Cold Weather Advisory from noon Friday to noon CST Saturday for NDZ001-002-009-010. Winter Weather Advisory until 6 AM CST /5 AM MST/ Friday for NDZ002>005-009>013-017>023-025-032>037-047. 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/ Friday for NDZ017>020-035.