Max, North Dakota Weather Forecast Discussion

902
FXUS63 KBIS 090559
AFDBIS
Area Forecast Discussion
National Weather Service Bismarck ND
1259 AM CDT Tue Sep 9 2025
.KEY MESSAGES...
- Areas of fog, possibly dense, along and east of Highway 83 and
  along and south of Highway 2 late tonight into Tuesday morning.
- Skies will remain smoky on Tuesday, with near-surface smoke
  returning to western North Dakota Tuesday afternoon.
- Low to medium chances for showers and thunderstorms return for
  the second half of the week through the upcoming weekend.
&&
.UPDATE...
Issued at 1256 AM CDT Tue Sep 9 2025
Pockets of showers continue to drift east-souteast across western
and central North Dakota, with a few thunderstorms across the south.
This activity is likely being sustained by a cyclonic mid level
flow. High-resolution and rapid refresh guidance remain persistent
in a dry forecast beyond model initialization time, which has proven
to be inaccurate. Confidence in the duration of this activity is
therefore low, but a corridor of drier air noted on water vapor
imagery entering northwest North Dakota should suppress convection
as that feature pushes southeast through the night.
Areas of fog are beginning to develop across the James River Valley.
Most guidance that simulates surface visibility suggests a
widespread dense fog event along and east of Highway 83, and along
and south of Highway 2. Wonder if clouds associated with the showers
moving over this area will impede fog development or at least limit
its spatial coverage. If the model guidance is accurate, a Dense Fog
Advisory may be needed by sunrise.
UPDATE
Issued at 950 PM CDT Mon Sep 8 2025
Scattered weak to moderate reflectivities linger over portions
of western and central North Dakota at the time of the late
evening update. While dry near surface to mid level conditions
linger over the southwest and north central, the column has
begun to saturate in the northwest and south central where
showers have been more persistent. These same areas continue to
observe the occasional rumble of thunder this evening, though
these have become very infrequent after sunset. With this
update, have modified PoPs in accordance with the latest radar
trends. Otherwise, we have expanded patchy fog over much of
central North Dakota tonight through Tuesday morning. High
resolution models are in strict agreement in visibility
reductions along and to the east of Highway 83, and with
portions of the James River Valley already hitting dewpoint
temps this evening its hard to disagree. Winds may remain a
little too strong and cloud cover a little too persistent to
allow for more widespread fog development, but that also remains
a possibility. We will continue to monitor this potential
overnight.
UPDATE
Issued at 630 PM CDT Mon Sep 8 2025
Isolated pockets of weak to moderate radar returns have
developed across much of western and central North Dakota. Dry
conditions found near the surface and at the mid levels are
expected to keep much of this precipitation from reaching the
ground, instead falling as virga. That being said, pockets of
more moderate instability across south central North Dakota has
promoted a few thunderstorms to develop which could allow some
light rain to reach the ground. Due to the dry near surface
conditions, isolated gusts up to 50 MPH are also possible with
any stronger storm that does develop. However, a poorly sheared
environment keeps the potential for severe weather very low
this evening. Update wise, have updated PoPs to account for the
slightly stronger storms in the south central. After
interrogating BUFKIT model soundings, we have also included
patchy fog across much of the James River Valley early tonight
through Tuesday morning. Some high resolution models hint at
greater visibility reductions during this period, though that
may depend on winds becoming weaker than what is currently
anticipated.
&&
.DISCUSSION...
Issued at 230 PM CDT Mon Sep 8 2025
Quasi-zonal flow aloft continues across the region as a weak
surface low and warm front lift through the region. The warm
front continues to bring warmer temperatures to the region as
the southwest has warmed up into the mid 80s. There are also
some shower chances and across the southwest this afternoon.
Smoke continues to filter in from eastern Montana impacting the
southwest mainly. The HRRR Smoke model has the main push of
surface smoke filtering into the Northwestern South Dakota
tonight. Overnight lows are forecast to drop down into the upper
40s north to lower 50s south.
An upper level ridge is forecast to amplify across the Plains
Tuesday leading to another round of near to above normal
temperatures through the week. However, high clouds and elevated
smoke will likely keep high temperatures a few degrees cooler
then today before temperatures jump back up Thursday. The
aforementioned upper level ridge will pass over during the
middle of the week.
Lee troughing east of the Northern Rockies and surface high
pressure over the Great Lake will lead to a north south
orientated pressure gradient. This will increase winds across
the state Wednesday and Thursday leading to breezy conditions. A
wave is forecast to move into the region late Wednesday brining
in a shot for showers and thunderstorms. Daily low to medium
chances for showers and thunderstorms will continue through the
end of the week as shortwaves move through the region. The
pattern looks to be more active this coming weekend as a broad
trough could move through the region.
&&
.AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/...
Issued at 1256 AM CDT Tue Sep 9 2025
Isolated showers and thunderstorms may continue across parts of
western and central North Dakota overnight. Areas of fog are likely
to develop across central and eastern North Dakota overnight into
Tuesday morning, with IFR/LIFR visibility and ceilings. The highest
probability for IFR/LIFR conditions is at KJMS and surrounding
areas. Fog/low ceilings should dissipate by late Tuesday morning.
Areas of smoke could return to western North Dakota Tuesday
afternoon, but forecast confidence in visibility restrictions below
VFR is low. Winds should remain light and variable through the
forecast period.
&&
.BIS WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
UPDATE...Hollan
DISCUSSION...Johnson
AVIATION...Hollan

NWS BIS Office Area Forecast Discussion