613
FXUS63 KBIS 191751
AFDBIS

Area Forecast Discussion
National Weather Service Bismarck ND
1251 PM CDT Sat Sep 19 2026

.KEY MESSAGES...

- Cloudy, humid, and cool today.

- Rain chances increase south and west of the Missouri River
  today, then medium to high rain chances remain tonight and
  through the day Sunday, before tapering Sunday night.

- Seasonable temperatures through early next week, with highs
  mostly in the 60s and 70s.

&&

.UPDATE...
Issued at 1251 PM CDT Sat Sep 19 2026

Light returns are present mainly across parts of the southwest
and south central, though any rain within the forecast area
remains light. Dense fog has lifted, while patchy drizzle/fog
continues mainly in portions of the northwest and north central.

UPDATE
Issued at 923 AM CDT Sat Sep 19 2026

Variable visibility remains across the forecast area with a few
observations, mainly in the north, reporting quarter mile or
less visibility. The highest concentration of lower visibility
is in the far northwest along Highway 2 from Williston to
Stanley. However, even then it appears relatively patchy in
nature based on webcams in the vicinity. Visibility should
improve through the morning, though may remain 1 to 3 miles at
times for parts of the forecast area, especially in the
southwest.

UPDATE
Issued at 616 AM CDT Sat Sep 19 2026

No changes to the going forecast. We issued a SPS for fog,
mainly along and south of the I-94 corridor. A couple of spots
are down to a quarter mile, but most are 1-3SM or better.

&&

.DISCUSSION...
Issued at 207 AM CDT Sat Sep 19 2026

An upper level lower pressure system currently spinning over
Idaho, will move into Wyoming this evening, and eventually into
western South Dakota by Sunday evening. This will bring abundant
cloud cover to western and southern portions of the forecast
area through the weekend. In addition, areas mainly south and
west of Lake Sakakawea and the Missouri River will see
accumulating precipitation.

Currently, low stratus and fog covered much of southwest and
south central ND. Portions of the northwest and north central
were free of low stratus, but remained covered with mid and high
level clouds. For the most part, western and central ND
remained precipitation free early this Saturday morning.
However, patchy light drizzle remained over portions of the
area. At 3 AM CDT, very light drizzle was falling at WFO
Bismarck. There were a couple of webcams along I-94 depicting
some light drizzle as well. Drizzle was more widespread around
midnight in this area, but there is some still falling. Luckily
the impacts are negligible. There are some lower vsbys, mainly
1-3SM in the south, but with widespread stratus south and high
cloud cover north, the threat for widespread dense fog looks to
be low.

For today, will maintain the forecast temperatures introduced
last evening with slightly cooler high temperatures than
guidance, given the widespread low cloud cover. Will keep a
mention of drizzle in the south central through 12Z and will
re-evaluate. Otherwise just a slight chance of rain along the
slow moving cold fron dropping south from Canada, and slight
chance, increasing to chance pops in the far west central and
southwest, and slowly advancing eastward.

Tonight, and through the day Sunday will bring categorical rain
over the far southwest, with medium to high chances for rain
along the Missouri River. HREF probabilities of 24 hour
precipitation of at least a half inch, from 7 PM Saturday
through 7 PM Sunday, range from 40 to 80 percent, right along
the Montana and South Dakota borders, from northern Golden
Valley County south to Bowman County and from Bowman county east
through Adams County. The probability for at least a tenth of
an inch for this same timeframe, ranges from less than 10
percent just north and east of the Missouri River to greater
than 40 percent only a few miles south and west of the Missouri.

Precipitation is expected to taper from north to south, west of
the Missouri River Sunday night, with dry conditions expected
by Monday morning. It looks like a couple of dry days to begin
the work week, Monday and Tuesday. We then see a couple of low
waves tracking through the area, the first around mid-week and
the next over the weekend. NBM is currently depicting low to
moderate precipitation chances (20 to 40%) with each wave. After
some cooler temperatures this weekend, the NBM is advertising a
warm-up through the work week. Ensemble spreads, at least
through around Thursday, are noticeably tighter than the past
couple of day, thus confidence is increasing that we see a
gradual warm-up through the week. On Thursday current NBM
temperatures range from the lower 70s east to the lower 80s
west.

&&

.AVIATION /18Z TAFS THROUGH 18Z SUNDAY/...
Issued at 1251 PM CDT Sat Sep 19 2026

MVFR/IFR/LIFR ceilings are present across the vast majority of
western through central North Dakota, including the James River
Valley. There will likely be some improvement further north and
east, but lowering ceilings are likely across much of the area
again tonight. VFR visibility is present across most of the
south with MVFR/IFR visibility along with patchy drizzle across
parts of the north. Northern visibility should also improve
through the afternoon, though localized reductions are possible
again tonight. Light rain is developing in southwestern and
parts of south central North Dakota. Overall, most accumulating
rain is expected to stay south and west of the Missouri River
with lesser amounts north and east.

&&

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

&&

$$

UPDATE...Telken
DISCUSSION...TWH
AVIATION...Telken