887
FXUS63 KBIS 251943
AFDBIS

Area Forecast Discussion
National Weather Service Bismarck ND
243 PM CDT Fri Sep 25 2026

.KEY MESSAGES...

- Medium to high chances for light rain from the Turtle
  Mountains south through the James River Valley and eastward.

- Temperatures favored to remain near to slightly above average
  until late next week.

- High chances for showers and thunderstorms Sunday evening
  through Monday night for all but northwest North Dakota.

&&

.DISCUSSION...
Issued at 1259 PM CDT Fri Sep 25 2026

Currently, low cloud remains across central and eastern North
Dakota, with only some high clouds in the west. Temperatures
were mainly in the 60s , except low to mid 70s under the more
abundant sunshine out west.

For tonight, most guidance suggests that the stratus will work
back to the west as a south to southeast return flow strengthens
over North Dakota ahead of a surface low situated over western
Canada. We do not anticipated widespread dense fog like we have
seen the past two mornings because of the increasing surface
gradient. However, some patchy fog can not be ruled out.
Guidance has been suggesting southern portions of the forecast
area, and added a mention of patchy fog later tonight into
Saturday morning. Latest guidance also keeps the mention of rain
from the Turtle Mountains into the James River Valley and
eastward late this afternoon through tonight. There is a
timeframe later this evening where low pops do extend back to
near the Missouri River in the south central, before shifting
back to the east after midnight. With the saturated lower layers
and some weak low level omega, we could see some patchy drizzle
extending west of the main precipitation area, to the Highway
83 corridor. Will monitor, but too uncertain to add a mention at
this time. On Saturday, the cold front associated with the
Canadian low pressure system swings west to east through the
forecast area. This will clear out the low stratus and shift
winds from southerly to northwest. Although it won`t be much
colder behind the front, it will be noticeably drier. Highs will
be mainly in the upper 60s to mid 70s across the forecast area
Saturday. Look for breezy southerly winds central early in the
day and breezy northwest winds over western ND late morning and
into the afternoon. High pressure builds over the area Saturday
night through a good portion of the day Sunday. Look for lows in
the lower 40s to lower 50s Saturday night and highs on Sunday
in the mid 60s to lower 70s.

Another upper level trough then looks to impact our weather
later in the day Sunday, through Monday night. A lead shortwave
propagating through a northern California upper trough will
induce cyclogenesis over the central High Plains, with an
inverted surface trough extending into the northern Plains by
early Monday. A northern stream wave may induce convection over
the Mondak region late Sunday, and into Sunday evening. Strong
bulk shear will be situated over the area. MLCAPE of
500-1000J/KG lifts from South Dakota into southwest ND Sunday
afternoon. Currently we have a general thunderstorm risk form
SPC Sunday. A stronger storm can not be ruled out with some hail
the most likely threat due to the likely elevated nature of the
storms. The entire system spreads east Sunday night through
Monday. Monday afternoon into early Monday may be another
potential for stronger storms as strong bulk shear weakens a
little but instability maybe greater from the south central into
the James River Valley. As mentioned in the previous
discussion, anomalously high Precipitable Water values and
possibly some training storms, may result in efficient rainers
with locally heavy rainfall Sunday night through Monday night as
the system works it`s way east across the forecast area.

We then dry out, at least for a while with a quasi-zonal flow
over the region and temperatures remaining near normal with
highs in the 60s to lower 70s and lows in the 40s through the
middle portion of the workweek.

&&

.AVIATION /12Z TAFS THROUGH 12Z SATURDAY/...
Issued at 1158 AM CDT Fri Sep 25 2026

Widespread stratus continues to lift over central ND with mainly
MVFR ceilings, but a few IFR ceilings do remain. Expect a
gradual improvement early this afternoon with areas west of a
lint from Bismarck to Bottineau lifting to VFR. Areas to the
east may remain MVFR through the day and tonight. In western ND
expect VFR conditions this afternoon as the stratus should hold
off for now. Tonight, expect stratus to expand back westward
with all TAF sites and most, if not all of ND seeing MVFR to IFR
ceilings, with perhaps a few areas see LIFR ceilings. At this
time we do not think that fog will be as prevalent as the past
few nights. Areas with cloud cover will see ceilings lower
tonight but stratus is favored over fog. Farther west, where low
clouds have yet to develop, there could be some patchy dense
fog develop, but southerly winds are expected to increase
through the day today, remaining breezy to windy tonight, thus
the fog potential seems to be limited, with lower stratus
favored here as well. Will certainly need to monitor though.
Southerly winds do remain breezy through the night across the
forecast area, then beginning around 12Z Saturday, a cold front
will move west to east, shifting winds to the northwest and
clearing the low stratus. By 18Z western ND should be clear from
the low stratus, with low clouds remaining over central ND.
Shower activity is expected over eastern ND tonight into
Saturday morning, mainly for areas along and east of the Turtle
Mountains through the James River Valley.

&&

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

&&

$$

DISCUSSION...TWH
AVIATION...TWH