801
FXUS63 KBIS 261813
AFDBIS

Area Forecast Discussion
National Weather Service Bismarck ND
1213 PM CST Wed Nov 26 2025

.KEY MESSAGES...

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

- There are medium to high chances (60-80 percent) for
  accumulating snowfall (up to 5 inches) Friday and Friday night
  across portions of western and south central North Dakota.

- Well below average 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 1210 PM CST Wed Nov 26 2025

The patchy and areas of fog continue in portions of the
northwest and north central. Else where the low clouds have
cleared, or lifted enough not to cause issues. The latest NBM
was loaded into the forecast and it looks the snow amounts have
increased for Friday into Saturday. Along with the probabilities
for more than 4 inches.

UPDATE
Issued at 925 AM CST Wed Nov 26 2025

Various areas of patchy dense fog are still on going,
especially in the north and south central. The very low stratus
causing this should continue to break up as diurnal heating
continues.

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 /18Z TAFS THROUGH 18Z THURSDAY/...
Issued at 1210 PM CST Wed Nov 26 2025

VFR to scattered MVFR this afternoon. Currently patchy to areas
of fog continue in the northwest and north central. Tonight the
fog will become much more widespread with IFR to LIFR CIGs and
VIS. Winds will mostly be northwesterly and light.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

UPDATE...Smith
DISCUSSION...NH
AVIATION...Smith