textproduct: Bismarck

KEY MESSAGES

- Windy with above normal temperatures today into Friday, then much colder Friday night through the weekend.

- Medium to high chances for accumulating snow across southwest and south central North Dakota Friday night through Saturday, with low to medium chances for a narrow band exceeding 3 inches.

- A return to above normal temperatures is favored for next week. A more active weather pattern could develop for the second half of next week.

UPDATE

Issued at 610 AM CST Thu Feb 26 2026

Overall, the forecast remains in good shape. One messaging change of note is the potential for near-critical fire weather conditions in far southwest North Dakota this afternoon, where minimum humidity could fall to around 30 percent with sustained westerly winds around 25 to 30 mph. This threat is highly contingent on fuel moisture, which is likely variable, but observed snow depth there is a trace at most.

DISCUSSION

Issued at 235 AM CST Thu Feb 26 2026

Northwest flow over the Northern Plains early this morning is becoming more anticyclonic as an underlying low level warm front has begun crossing the region. A strong westerly downslope flow with reinforcing Pacific air should allow temperatures to climb well above normal this afternoon. This setup favors high temperatures approaching the warmest quartile of NBM guidance in the absence of a deep snow pack, which is the case for most of our forecast area. The 75th percentile of the NBM distribution was therefore used for the high temperature forecast today, which ranges from the mid 30s in the Turtle Mountains area to the lower and mid 50s along and to the south and west of the Missouri River. The westerly winds could become strong this afternoon, especially in western North Dakota where gusts could reach 40 mph.

A deepening low pressure system is forecast to move from central Saskatchewan through Ontario tonight through Friday. An initial cold front is scheduled to cross the state from northwest to southeast late tonight into early Friday morning. Forecast magnitudes of cold air advection and pressure rises suggest a period of stronger winds could occur with this frontal passage, with surface gusts perhaps in the 40 to 50 mph range, but the overnight timing could also limit this potential. At least breezy conditions are expected through tonight though, which should keep overnight temperatures mostly in the 30s. A secondary but more potent cold front is then set to follow a similar path through the state mid Friday morning through the afternoon. This timing provides a much greater potential for momentum transfer of mean boundary layer winds to the surface, which could be as high as around 30 kts from northwest to south central North Dakota to as high as 50 kts in the northeast. A Wind Advisory may be needed on Friday from the Turtle Mountains through the James River Valley. Daily maximum temperatures on Friday could be observed before sunrise at many locations, especially across the north where the secondary cold front will move through prior to peak heating. The projected diurnal temperature trend ranges from a typical curve across the south to near-steady or falling across the north. Daytime highs are forecast to range from the 20s north to around 40 southwest.

The deepening Canadian low will increase cyclonic shear vorticity and frontogenesis over the region on Friday. A few CAMs are advertising some light snow moving from north to south across western North Dakota during the day Friday in response to this forcing, but this is not universal and think any snow amounts from this would be a dusting at most. This potential will not be widely messaged until or unless confidence increases. By Friday night though, a further amplification of cyclonic shear vorticity and low to mid level frontogenesis is expected to produce a band of snow with northwest-to-souhteast orientation that is likely to impact some, but not all parts of western and south central North Dakota. This feature has been present in global deterministic and ensemble models for several days, but with placement uncertainty that appears to have become even more pronounced in the 00Z set of guidance. Two ensemble clusters that compose a slight majority of all ensemble members place the highest QPF/snow probabilities along an axis between Highway 12 and a line from around Beach to Fort Yates. A GEFS- heavy minority cluster places this axis almost completely outside of the state to the southwest, while a differing ECMWF- heavy minority cluster places the axis as far north as around Watford City to Bismarck. Pairing conceptual modeling and subjective recollection of this type of setup yields the northern solution to be a far less likely outcome. In fact, even the NAMnest which has a well- documented north-bias with banded snow is more in line with the two majority ensemble clusters. For these reasons, we will limit the messaging of potential higher snow amounts to southwest and south central North Dakota for now.

There are several factors working both for and against an impactful banded snow event Friday night through Saturday. Factors working in favor of higher amounts include: 1) very strong frontogenesis, 2) climatologically high projected snow- to-liquid ratios of at least 20:1 given a deep and saturated dendritic growth zone with relatively light winds throughout, and 3) a long residence time of snowfall where the band sets up. Factors working against a more impactful banded snow event include: 1) weaker QG forcing that is not guaranteed to overlap with the strong frontogenesis and 2) weak mid level lapse rates. Overall ensemble probabilities for at least 0.20" of QPF, which would equate to around 4 inches of snow, have decreased since yesterday, but this may be a function of the increased spatial uncertainty. Once all CAMs' forecast time range extends through this event, which will be by the end of today, we should have a much better idea on the maximum snow potential for this event, but the location of highest amounts could remain uncertainty until near or even after the start of the event.

Aside from the banded snow potential, the other main story for the weekend is much colder temperatures. Saturday through Saturday night looks to be the coldest time period given the placement of a synoptic-scale Arctic surface high pressure from the southern Canadian prairie provinces to the Red and Upper Mississippi River Valleys. Highs on Saturday are forecast to range from the single digits above zero in the Turtle Mountains area to near 30 in the southwest corner of the state. Lows Saturday night are mostly forecast in the single digits above and below zero, coldest again in the Turtle Mountains area. A warming trend should commence on Sunday as the surface high slides eastward and milder Pacific air begins to filter back in from the west.

Ensembles are consistent with a northwest to quasi-zonal flow pattern Monday through at least Tuesday of next week that returns the temperature forecast to above normal. There could be a few embedded shortwaves with this pattern, but predictability on these smaller scale features remains low. By the middle of next week, we start to see a much more amplified pattern emerge in deterministic and ensemble guidance that could evolve into a predominant southwest flow pattern over the Northern Plains. The NBM temperature distribution remains quite large for mid to late next week, but still generally ranges from near normal (highs in the 30s) to well above normal for most of western and central North Dakota.

AVIATION /12Z TAFS THROUGH 12Z FRIDAY/

Issued at 610 AM CST Thu Feb 26 2026

VFR conditions are expected through the forecast period. Westerly winds will increase to around 15-25 kts this afternoon, with gusts to 35 kts in western North Dakota. It will remain breezy through tonight, and a cold front dropping down from Canada will begin turning winds to the northwest later in the night. Low level wind shear will impact much of southwest and south central North Dakota early this morning, then most of western and central North Dakota this evening through tonight.

BIS WATCHES/WARNINGS/ADVISORIES

None.