068
FXUS63 KBIS 301807
AFDBIS

Area Forecast Discussion
National Weather Service Bismarck ND
1207 PM CST Sun Nov 30 2025

.KEY MESSAGES...

- Well below average temperatures will continue this weekend
  into early next week. Wind chill temperatures as low as 25
  below zero will be possible both this morning and tonight.

- An active northwest flow is forecast for next week, with
  periodic chances for snow and moderate to large fluctuations
  in day-to-day temperatures.

&&

.UPDATE...
Issued at 1207 PM CST Sun Nov 30 2025

Low level moisture trapped under high pressure has continue to
bring low clouds and patchy to areas of fog. When this lifts is
an area of uncertainty, although may take until the area of high
pressure moves eastward and an upper level wave brings increased
winds aloft. For now extended fog mention in the forecast. Also
expanded the Special Weather Statement for fog and issued until
about mid afternoon. Otherwise the forecast remains on track.

UPDATE
Issued at 917 AM CST Sun Nov 30 2025

Low clouds continue to linger across much of the forecast area,
while some patchy to areas of fog, dense in some spots, has
formed in the northwest. Adjusted the forecast based on these
current trends. Fog in the northwest is expected to improve
through the morning. For now issued a Special Weather Statement
to inform of the potential impacts from pockets of dense fog
through the morning hours in the northwest.

UPDATE
Issued at 614 AM CST Sun Nov 30 2025

Increased fog a bit where it has developed, otherwise tweaked
sky cover again based on latest satellite and trends. See below
for further discussion and updated aviation discussion.

&&

.DISCUSSION...
Issued at 355 AM CST Sun Nov 30 2025

Currently, northwest flow aloft with an embedded S/WV trough
propagating southeast across the Northern Plains. Surface high
pressure slowly building across the western Dakotas, while deep
low pressure resides over the Midwest near the southern Great
Lakes region. Resultant pressure gradient maintains a steady
northwest breeze east of the sfc high, and when coupled with
temperatures in the single digits above and below, early morning
wind chills have dropped in the -15 to -25 range west and north
central. Low level clouds and scattered flurries persist, along
with some light snow downstream of Lake Sakakawea where some
lake enhancement is occurring thanks to the low level cold
northwest flow over the warmer lake waters.

Surface high pressure slowly moves east across the Dakotas
today, exiting to the southeast tonight. Cloud cover continues
to a forecast challenge, though the general trend is expected
to be decreasing cloud cover through the day today as subsidence
spreads across our area. While another cold night is forecast
tonight with expected decreased cloud cover and our recent
snowfall, increasing southerly return flow will keep
temperatures from bottoming out, plus another incoming embedded
wave may again result in some clouds materializing.

We remain in a northwest flow regime through next week, with
embedded waves periodically moving through aloft. One of these
waves and an associated strong cold front is favored to impact
the region Tuesday and Wednesday, bringing milder temperatures
on Tuesday (highs 25-35), snow chances Tuesday afternoon and
Tues night, and another cold period on Wednesday (highs in the
single digits and teens). Projected wind chills both Tue night
and Wed night will again approach 25 below zero, perhaps as cold
as 30 below zero Wed night before another milder airmass spreads
east across the Northern Plains.

The rest of the period will see high uncertainty/low
predictability as models will struggle with the smaller scale
features this far out. NBM continues to show a near 20 degree
spread in potential highs for the end of the week, with this
range only increasing into the following weekend. This is
typical for a northwest flow pattern in the winter with snow
cover on the ground.

&&

.AVIATION /18Z TAFS THROUGH 18Z MONDAY/...
Issued at 1207 PM CST Sun Nov 30 2025

Lingering low clouds and patchy fog could bring periods of MVFR
to IFR conditions, and perhaps brief LIFR conditions, through
this afternoon. While sites without low clouds and fog should
see VFR conditions this afternoon. Uncertainty remains on
location and timing of the lower visibility and ceilings through
this afternoon. For now used TEMPO groups in sites with highest
probability of seeing IFR conditions. Current forecast has most
site improving to VFR conditions this evening and through
tonight. There still remains some uncertainty to the amount of
clearing, although a weak disturbance aloft should switch winds
westerly and help diminish low clouds and fog. VFR conditions
are then forecast into Monday morning.

&&

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

&&

$$

UPDATE...Anglin
DISCUSSION...NH
AVIATION...Anglin