012 
FXUS63 KBIS 301028
AFDBIS

Area Forecast Discussion
National Weather Service Bismarck ND
528 AM CDT Fri Oct 30 2026

.KEY MESSAGES...

- Near to above normal temperatures are favored through the
  middle of next week. 

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

&&

.UPDATE...
Issued at 525 AM CDT Fri Oct 30 2026

A Dense Fog Advisory has been issued for Bowman, Adams, and
Slope Counties where widespread fog has been thick and
persistent. Will stick with a Special Weather Statement in 
northwest and north central North Dakota where dense fog is not
as widespread and has been observed to be variable outside of 
Divide and Burke Counties.

&&

.DISCUSSION...
Issued at 417 AM CDT Fri Oct 30 2026

An upper level ridge axis extends from the Northern High Plains
to the Gulf Coast early this morning while a closed upper low 
spins off the Pacific Northwest coast. A surface ridge axis is 
analyzed from Alberta to Wisconsin, cutting through the northern
Red River Valley. This places western and central North Dakota 
under a mostly benign weather pattern, with the only impactful 
phenomenon being areas of dense fog that appear to be driven by 
radiation processes near the Canadian border in northwest and 
north central North Dakota, and by advection and orographic 
processes in the southwest corner of the state. The general 
expectation is that fog in the far north will dissipate either 
after sunrise or if low clouds move over, while fog in the 
southwest is more likely to lift into a low stratus deck. The 
daytime hours today will feature more clouds than sun, with 
high temperatures forecast to reach the mid 40s to mid 50s. 

Mid level shortwave energy will begin to eject from the base of
a western CONUS trough by tonight as underlying low level 
southeasterly flow maintains a broad warm air and moisture 
advection regime over the Northern Plains. High-resolution 
models show favorable conditions for thick stratus with periods 
of drizzle developing in southwest North Dakota tonight and 
gradually spreading north and eastward through Saturday 
afternoon. Should this occur, the NBM high temperature forecast 
on Saturday of lower 50s to lower 60s would likely be 5 to 10 
degrees too warm, even with dewpoints rising into the mid 40s 
to mid 50s. A more well-defined mid level shortwave could bring 
light rain showers (as opposed to just drizzle) through the 
region Saturday night, but there is some uncertainty in the 
trajectory of the strongest forcing for ascent.

An overcast is likely to prevail over much of the forecast area
through Sunday, with drizzle remaining possible as well. A 
continuation of warm air and moisture advection should lead to 
warmer high temperatures on Sunday, though again perhaps not 
quite as warm as the mid 50s to mid 60s advertised by the NBM. 
A deep western CONUS trough will begin to translate into the 
Plains Sunday night, inducing lee cyclogenesis that is favored 
to produce a Colorado low. Strong QG forcing over the Northern 
Plains brings high chances for rain (70 to 95 percent) across 
the forecast area Sunday night through Monday evening. 
Temperatures will remain warm enough for precipitation to only 
fall as rain (Sunday night lows in the upper 30s to upper 40s), 
and there may actually be enough MUCAPE to support a couple of 
elevated thunderstorms Sunday night into Monday morning. There 
has been a notable shift in ensemble data to both much higher 
QPF amounts/probabilities and the areal footprint thereof. The 
QPF gradient now increases from northwest to southeast, with 
medium chances for exceeding half an inch of rain and low 
chances for exceeding 1 inch. There is still uncertainty on the
timing of the departure of the system, but recent ensemble 
guidance is trending toward lighter rain lasting into Tuesday, 
at least for the eastern half of the state. 

The synoptic pattern for mid to late next week looks to be 
highly-amplified, but could feature predominant ridging over 
the central CONUS. This keeps the forecast dry after Tuesday, 
with seasonable temperatures of highs in the mid 40s to mid 50s
and lows in the lower 20s to lower 30s.

&&

.AVIATION /06Z TAFS THROUGH 06Z SATURDAY/...
Issued at 417 AM CDT Fri Oct 30 2026

Dense fog is possible across parts of western and central North
Dakota this morning, but is unlikely to impact any TAF sites. 
There is a low chance that MVFR/IFR ceilings could move over 
KDIK this morning. VFR conditions are generally otherwise 
expected through this afternoon, although some pockets of MVFR 
ceilings cannot be ruled out. MVFR ceilings are then forecast to
become more common later this evening through tonight. Expect 
easterly winds through the forecast period, with speeds around 
5-10 kts this morning increasing to 10-15 kts this afternoon.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
Dense Fog Advisory until 10 AM MDT this morning for NDZ040-043-
044.

&&

$$

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