textproduct: Bismarck

KEY MESSAGES

- Long duration of bitterly cold temperatures with dangerous to life-threatening wind chills through the weekend.

- Coldest conditions are expected this morning, with low temperatures around 25 to 35 below zero and wind chills as low as 55 below zero.

- Temperatures favored to warm next week, but could still remain below normal.

UPDATE

Issued at 521 AM CST Fri Jan 23 2026

The forecast remains on track. Widespread temperatures around 20 to 35 below and wind chills around 45 to 55 below across western and central North Dakota this morning. Stay indoors to the greatest extent possible!

DISCUSSION

Issued at 255 AM CST Fri Jan 23 2026

Life-threatening cold in place this morning, with widespread temperatures in the 20s and 30s below and wind chills in the 40s and 50s below. At 2 AM CST, an oblong surface high pressure with maximum MSLP of 1048 mb was centered from southern Saskatchewan through western North Dakota. The high is forecast to slide southeastward through the day, with the associated lighter winds contributing to poor boundary layer mixing under an already intense Arctic inversion. We continue to keep our high temperature forecast for today colder than the deterministic NBM output, but it is still warmer than the 50th percentile of the NBM distribution. Forecast highs are mostly in the teens below zero, with a handful of single digits below zero in the far southwest and southern James River Valley. The lighter winds will allow wind chills to improve to around 15 to 30 below this afternoon, which can still be dangerous if not dressed properly.

A mid level shortwave is forecast to glide across the region tonight, inducing a very slight warming of the lower levels. This will likely keep temperatures from tanking overnight, but given how cold the high temperature forecast is, we are still expecting around 15 to 30 below for lows. A light southerly breeze will push overnight and Saturday morning wind chills into the 30s and 40s below. The Extreme Cold Warning remains in effect north and east of the Missouri River, and areas to the south and west will likely need a Cold Weather Advisory for tonight through Saturday morning. This decision will be made at the conclusion of the ongoing warning later this morning. Flurries can never be ruled out when there is a forcing mechanism moving through or over Arctic air, but model soundings look extremely dry tonight, and the radius of influence of the surface high still reaches the area.

Saturday could see an appreciable rebound in temperatures compared to today, but highs will still mostly be limited to the single digits below zero north and above zero south. Another mid level shortwave is forecast to push a reinforcing shot of Arctic air down from Canada Saturday night, allowing temperatures to once again fall into the teens and 20s below zero. NBM winds around 5 mph look to be a little too light Saturday night given the expected cold air advection and pressure rises, which means our current minimum wind chill forecast of around 25 below southwest to 45 below northeast may not be cold enough. Nevertheless, the Extreme Cold Warning continues through Sunday morning north and east of the Missouri River.

There is some model support for light snow moving through southwest North Dakota ahead of the shortwave late Saturday afternoon through Saturday night. In raw global ensemble data, the probability of measurable snow over this time frame ranges from around 40 percent from Williston to Fort Yates to as high as 80 percent southwest of Dickinson. The calibrated NBM probabilities for measurable snow are quite different at only around 5 percent southwest to 15 percent south central. Did not make any adjustments for this forecast package, but think that at least a mention of flurries will eventually need to be added.

Sunday is now expected to be colder than Saturday on the heels of the reinforcing shot of Arctic air, with forecast highs around 10 below northeast to barely above zero southwest. Sunday night will still be frigid, but the passage of a Pacific warm front over the residual Arctic air could at least keep overnight temperatures in the single digits (west) and teens (east) below zero. While life- threatening wind chills are not in the forecast for Sunday night through Monday morning, a Cold Weather Advisory may still be needed for some areas.

Ensemble spread over the Monday to Wednesday time frame next week has shrunk to some extent. Confidence has increased that Monday will be a much warmer, but perhaps windy day as the region lies within the warm sector of a clipper system passing well to our north and east. Forecast highs for Monday range from the teens northeast to 20s southwest. Then through the middle of next week, a sharp baroclinic zone under northwest flow aloft is forecast to set up over the Northern Plains. This gives high confidence in the common wintertime temperature pattern of coldest northeast to warmest southwest, but magnitudes remain uncertain on account of the exact placement of the baroclinic zone. The NBM would imply it is more likely to lie over western North Dakota (colder solution - below normal) than central North Dakota (warmer solution - near normal), but clusters are more evenly split on its placement. Then late next week, ensemble spread becomes greater as a western CONUS ridge looks to clash with a retrograding Hudson Bay low. By Friday, the NBM median 50 percentile spread in maximum temperature is around 20 to 25 degrees, but the entire distribution does shift slightly warmer. Clusters late next week show near equal probabilities of a colder (below normal) vs. warmer (above normal) outcome. Precipitation prospects remain uncertain for all of next week. 6-hour NBM probabilities are no greater than 15 percent at any given location and time range.

AVIATION /12Z TAFS THROUGH 12Z SATURDAY/

Issued at 521 AM CST Fri Jan 23 2026

VFR conditions are expected through the forecast period. Northwest winds around 10 kts this morning will become light and variable through the afternoon.

BIS WATCHES/WARNINGS/ADVISORIES

Extreme Cold Warning until noon CST Sunday for NDZ001>005- 009>013-021>023-025-035>037-046>048-050-051. Extreme Cold Warning until noon CST /11 AM MST/ today for NDZ017>020-031>034-040>045.