671
FXUS63 KBIS 151946
AFDBIS

Area Forecast Discussion
National Weather Service Bismarck ND
246 PM CDT Tue Sep 15 2026

.KEY MESSAGES...

- Near normal temperatures in the mid 60s to mid 70s through the
  week, although some cool morning lows could be found
  Wednesday and Thursday.

- Low chances for showers Wednesday. Better chances for showers
  and thunderstorms across the area late in the work week and
  into the weekend.

&&

.DISCUSSION...
Issued at 245 PM CDT Tue Sep 15 2026

Northwest flow will lessen tonight under weak ridging. Some
trapped moisture aloft in this northwest flow could continue
some low clouds through the evening, with some partial clearing
expected tonight. This partial clearing will influence low
temperatures tonight, with lows generally in the 40s. Some clear
areas with light winds could see lows into the 30s, perhaps
bringing isolated frost. As a surface low develops to our
west, light winds will become a steady southeasterly flow later
tonight especially in the west. Inverted surface trough then
moves through Wednesday, combined with a weak mid level
wave/warm front then trailing cold front. The result will be
some chances for showers mainly central, north, and east. Some
weak and elevated instability could provide for a few isolated
thunderstorms as well on Wednesday. Shear is high Wednesday, but
will likely not be full accessible given the elevated nature of
any thunderstorms that develop. Slightly warmer temperatures
will also be found on Wednesday, especially in the southwest,
with highs generally forecast in the 60s north and east to 70s
elsewhere. Breezy southerly winds may also be found as well at
times on Wednesday. Cold front moves south out of Canada
followed by a surface high Wednesday night into Thursday
morning. This will bring cooler lows in the mid 30s to mid 40s.
Depending on winds and cloud cover some patchy frost is
possible, especially across the north.

Surface high will bring mainly dry conditions on Thursday,
although a stalled front and return flow could bring some
showers and thunderstorms to the southwest. Most of the
precipitation is expected to remain to our south Thursday,
perhaps clipping some southern portions Thursday night. Winds
will again be easterly, and could be breezy in the southwest.
Cooler highs in the 60s to near 70 can be expected behind
Wednesday nights cold front. Abundant moisture combined with a
broad upper low could then bring widespread shower and
thunderstorm chances of Friday. How far north and east this
plume of moisture and the upper low goes will determine where
the precipitation sets up. Current PoPs favor the northwest and
some southern portions of the state for Friday. Temperatures
warm slightly for Friday, and generally in the 70s. Broad upper
low and trough slowly moves into the area this weekend keeping
temperatures near to slightly below normal. As a result broad
chances for showers and thunderstorms will be across the state
through the weekend. Actual location of precipitation will be
highly dependent on intrusion of dry and limited synoptic lift
at times. Even so NBM still showing 40 to 60% chance for 0.5" or
greater of rain through the weekend, mainly along and west of
Highway 83. Limited instability and shear should also limit the
thunderstorm threat for the weekend. With high RH values at
night there could be some patchy fog at times this week into the
weekend. Highly dependent on winds and precipitation though.
Thus have left it out of the forecast for now. With cloudy skies
this weekend, lows should be mild limiting the frost potential.

&&

.AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/...
Issued at 1240 PM CDT Tue Sep 15 2026

Low VFR to MVFR ceilings could linger through tonight across
much of the forecast area. VFR conditions are then expected
tonight into Wednesday morning. Breezy northwest winds will
become variable tonight, then become a steady east southeast
wind for Wednesday. Some showers could return later in the
morning Wednesday and continue through the day. Confidence in
these showers was too low to include in the TAFs at this time.

&&

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

&&

$$

DISCUSSION...Anglin
AVIATION...Anglin