textproduct: Bismarck

KEY MESSAGES

- Areas of dense fog across parts of western North Dakota this morning, and across much of western and central North Dakota tonight through Thanksgiving morning.

- There are medium to high chances (60-80 percent) for light accumulating snowfall (up to 3 inches) Friday and Friday night across portions of western and central North Dakota.

- Well below normal temperatures are favored for this coming weekend and into early next week. Wind chill temperatures as low as 25 below zero will be possible both Saturday night and Sunday night.

UPDATE

Issued at 615 AM CST Wed Nov 26 2025

No big changes with this update, again mainly to tweak sky cover to better account for latest satellite imagery and trends. Areas of fog west, but not widespread enough to warrant any elevated messaging at this time outside of the HWO. Will continue to monitor.

DISCUSSION

Issued at 405 AM CST Wed Nov 26 2025

Currently, strong northwest flow aloft with broad ridging over the eastern Pacific/West Coastal area, and an upper level low over the Western Great Lakes region. Surface ridge of high pressure over the western Dakotas, with continued pressure rises/gradient forcing central and east. Temperatures this morning have plummeted where the sky is clear and winds are light, down to the single digits below to around zero northwest. Warmer central and east where some low level cloud cover remains and where a steady northwest breeze is keeping the boundary layer mixed enough.

Northwest flow aloft remains over the region today and tonight, with the sfc ridge quasi-stationary west today then slowly developing east into the central Dakotas tonight. Widespread snowfall coupled with light winds and little temperature advection will see chilly daytime highs in the low to mid 20s most areas west and central today, maybe not even breaking 20F some areas depending on how low morning temperatures drop. Some return flow and weak WAA southwest, where highs will be around 30.

Expecting another round of fog developing along the sfc ridge axis tonight northwest and central, with latest CAMs in decent agreement with both timing and aerial coverage. Dense fog will be possible through Thanksgiving morning, (and possibly into the afternoon as the sfc ridge remains quasi-stationary/slowly developing east). See no reason to take this out of the HWO, especially considering Thanksgiving Day travel.

Northwest flow aloft remains for the remainder of the week and through this coming weekend, maintaining below normal temperatures. Our next chance of precipitation arrives on Friday and lasts through Friday night/Sat morning. Initially we have split flow aloft, with a vigorous S/WV moving into the Pacific Northwest Thursday, which then phases with a northern stream wave Friday as it develops east into the Northern and Central Rockies. This will induce surface low pressure developing in the lee of the Rockies, with an isentropic upglide forcing regime developing over the western and central Dakotas by Friday morning. Snow is forecast to develop Friday morning and continue into Friday night as the main wave along with embedded impulses move through aloft. There may be some banding potential as well, with models showing Div Q/frontogensis linkage at least initially Friday morning/aft.

Ensembles (GEFS/EC) are in near agreement with the placement of snow and accumulation probabilities, thus the NBM POPs have increased along with NBM probs for 1, 2, and 3 inches of snowfall. Watford City to Jamestown and points south are favored (up to 80% chance for an inch...40-60% for 2), with lesser chances to the north and far southwest (less than 20%). GEFS/EC Ens Probs for 3 inches peak at around 60% south central, so def picking up on the banding potential. Will continue to message this period in the HWO in addition to social media.

Large upper low settles over Hudson Bay to our north-northeast this weekend, and will push a surge of Arctic air south into the north central CONUS. Coldest period is currently expected to be Sunday, when high temperatures are only forecast in the single digits and teens, along with widespread subzero lows Sat night, Sun night, and Mon night. Thereafter, uncertainty increases as a persistent northwest flow maintains a baroclinic zone waffling west and east, resulting in our typical temperature distribution of colder northeast and warmer southwest.

AVIATION /12Z TAFS THROUGH 12Z THURSDAY/

Issued at 542 AM CST Wed Nov 26 2025

A mix of VFR/MVFR ceilings this morning, as well as LIFR cigs/vis west where fog has developed. Winds remain out of the northwest central and east through the 12Z period, and more light and variable west. Another period of IFR-LIFR cigs and vis expected this evening into Thu morning west and central as fog again develops.

BIS WATCHES/WARNINGS/ADVISORIES

None.