045
FXUS63 KBIS 310659
AFDBIS

Area Forecast Discussion
National Weather Service Bismarck ND
159 AM CDT Sat Oct 31 2026

.KEY MESSAGES...

- Low clouds and fog return overnight, lingering into Saturday.

- Near to above average temperatures are favored through the
  middle of next week. High temperatures will be dependent on
  low cloud cover the next few days.

- Low chances for light rain and drizzle tonight through Sunday,
  then high chances for rain Sunday night through Monday night.

&&

.UPDATE...
Issued at 158 AM CDT Sat Oct 31 2026

Current conditions and trends were blended into the forecast
for this update. Low stratus is a little slower to advance
northward from South Dakota than guidance had indicated.
Surface observations and radar also suggest that any drizzle or
light rain has yet to develop within the forecast area.

UPDATE
Issued at 930 PM CDT Fri Oct 30 2026

Low stratus continues to expand western and south central ND
from the central Plains. Latest satellite imagery shows some
mostly clear skies from central into eastern ND late this
evening. Will adjust sky cover to adjust for this. Also slowed
the increasing clouds here overnight. Guidance suggests low
clouds will continue to increase overnight and Saturday morning.
Some question as to how widespread any fog may be late tonight
into Saturday. Bufkit guidance suggests more potential for
stratus than fog. Previous forecast had a mention of patchy fog
over much of western and central ND, with areas of fog
southwest. This seems reasonable for now. Adjusted pops down
this evening,

UPDATE
Issued at 623 PM CDT Fri Oct 30 2026

Low clouds continue to expand northeastward where much of the
forecast area will be covered by low clouds by tomorrow morning.
Patchy dense fog is possible tonight and early tomorrow morning
across the southwest likely expanding into the south central
and northwest. No major updates are needed to the forecast as
the forecast remains on track.

&&

.DISCUSSION...
Issued at 127 PM CDT Fri Oct 30 2026

Current surface analysis places low over the Great Basin nudging
towards the northern Rockies, while high is situated over the
southern Prairie Provinces into the upper Midwest. Upper level
analysis places low off the Pacific Northwest, with ridge over
the central/northern plains. Over our area, light easterly flow
is keeping some low clouds/fog anchored over parts of southwest
North Dakota. The fog has remained dense over far southwest
North Dakota where a Dense Fog Advisory remains in places
through 1PM MDT, but some improvement in visibility has been
noted on area webcams and observations so plan to let it expire
at that time.

For the rest of today into tonight, low level southeast flow
remains in place, with clouds and some fog returning from
southwest to northeast overnight. A variety of weak waves
lifting ahead of aforementioned upper trough may bring a few
weak light showers to the area, in addition to some possible
drizzle given the light upslope moist low level flow.

As we get into tomorrow, light upslope flow continues with
clouds lingering over the area. Main concern with this is its
influence on temperatures as think latest NBM is much too
optimistic with its high temperature forecast. Therefore, have
leaned towards NBM10 which still may be too optimistic over the
south central/southwest, but at least it starts the downward
trend. Have also kept the potential for fog in the forecast
through mid-day. Given the light southeasterly low level flow
continuing into Saturday night and Sunday morning, have
returned the fog throughout the area.

Precipitation chances will be on a significant increase Sunday
night into Monday as the aforementioned upper low works its way
over the Rockies, and a surface low spins up to the lee of the
Central Rockies and ejects into the central plains. This looks
to bring widespread precipitation to the area, though
temperature profiles remain warm enough so this should remain
liquid. A few rumbles of thunder from an elevated thunderstorms
can not be ruled out over southern portions of the area.

Thereafter some questions remain with the forecast as guidance
has been leaning towards ridging, but some ensemble members lean
towards a bit more active pattern. With that said, temperatures
look to remain seasonal.

&&

.AVIATION /06Z TAFS THROUGH 06Z SUNDAY/...
Issued at 158 AM CDT Sat Oct 31 2026

Low ceilings are expected to spread across the state from south
to north tonight through Saturday morning, settling at mostly
LIFR across the south to MVFR across the north. Improvement to
IFR or low MVFR is possible in southern North Dakota Saturday
afternoon before IFR to LIFR ceilings spread across the whole
state Saturday night. Periods of mist and drizzle are possible
under the low clouds, which may reduce visibility to MVFR or IFR
levels at times. Winds will remain easterly to southeasterly
around 5-10 kts through the forecast period.

&&

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

&&

$$

UPDATE...Hollan
DISCUSSION...JJS
AVIATION...Hollan