632
FXUS63 KBIS 020958
AFDBIS

Area Forecast Discussion
National Weather Service Bismarck ND
358 AM CST Mon Nov 2 2026

.KEY MESSAGES...

- Rain today, tapering off from northwest to southeast this
  afternoon through tonight, but continuing in the James River
  Valley into Tuesday.

- Medium to high chances for at least 1 inch of rain along and
  south of Highway 200, and for at least 2 inches of rain in
  the southern James River Valley.

- Windy today into Tuesday, strongest across the far southwest
  and south central.

- Near to above average temperatures and drier weather are
  favored later in the week.

&&

.DISCUSSION...
Issued at 358 AM CST Mon Nov 2 2026

A deep upper level trough is crossing the Northern and Central
Rockies early this morning, with a series of lee surface
cyclones developing from southeast Montana to northeast
Colorado. The southern most surface low will become the
dominant feature and quickly move northeast into eastern South
Dakota by this afternoon. Intense synoptic scale lift will
produce widespread rain across the state this morning, tapering
off from northwest to southeast this afternoon through tonight.
However, there is an emerging solution supported by recent
initializations of the HRRR, RAP, REFS, and even the NBM to
some extent that stall the low over southwest Minnesota through
Tuesday, which would keep persistent rainfall over the James
River Valley. Probability-matched mean rainfall from high-
resolution ensembles is consistent with NBM calibrated QPF,
which places at least 1 inch of rain from south central North
Dakota to the James River Valley, and also in west central
North Dakota, mainly over the Badlands. There are also medium
to high chances for exceeding 2 inches of rain along and east
of a line from around Linton to Carrington. Despite a lack of
buoyancy, poor mid level lapse rates, and some uncertainty on
the strength and location of low to mid level frontogenesis,
other ensemble tools, such as the ECMWF EFI QPF and NAEFS
precipitable water exceeding the climatological maximum values,
lend further confidence to rain amounts this high. This is
especially true if rain continues over the James River Valley
through Tuesday, which could result in some locations receiving
over 3 inches of rain. The lowest rain amounts are forecast
along the Canadian border, where there are still medium chances
for exceeding half an inch of rain.

The tightening of the surface pressure gradient will induce
windy conditions today, lasting into Tuesday across southern
and moreso eastern North Dakota. Model soundings continue to
show very poor momentum transfer, but that could be overcome by
the strong dynamics of the system. Confidence in a longer
duration of sustained winds around 30 mph is high enough for a
Wind Advisory in areas south of I-94 and west of the Missouri
River, which is in effect from mid morning through late evening
today. An advisory may be needed east of the river on Tuesday
if the system does stall over southwest Minnesota, but model
soundings continue to show very poor mixing potential.

Expect near-steady or slowly falling temperatures through this
afternoon, with mid 40s northwest to mid 50s south central and
east. The low temperature forecast for tonight and high
temperature forecast for Tuesday are highly dependent on the
progression of the low and associated cloud cover. Forecast
lows below freezing in western North Dakota tonight are likely
only achievable if clouds begin to clear before sunrise Tuesday
morning. Forecast highs on Tuesday are in the mid to upper 40s,
but these could end up cooler if the slower progression
scenario verifies not only due to persistent cloud cover, but
also due to stronger cold air advection.

Ensembles favor a pseudo omega blocking pattern over broad
surface high pressure Wednesday and Thursday that could
transition to a progressive northwest flow pattern to end the
week. 3 out of 4 global ensemble clusters do pick up on a more
potent shortwave digging down from Canada on Saturday in the
form of an Alberta clipper. The NBM maintains near to above
normal temperatures from the middle of the week through the
weekend, with highs in the 40s and 50s and lows in the 20s and
30s.

&&

.AVIATION /06Z TAFS THROUGH 06Z TUESDAY/...
Issued at 358 AM CST Mon Nov 2 2026

A strong storm system currently over northeast Colorado will
track northeast to west central Minnesota by 06 UTC Tuesday.
Widespread low clouds and areas of fog will remain across the
state with most areas seeing mainly IFR-LIFR ceilings and MVFR
to IFR visibilities through the TAF period. Rain will continue
this morning and taper off from northwest to southeast this
afternoon and evening.

Winds shift from southeast to east to northerly from west to
east this morning and increase to 15 to 25 mph. Winds turn
northerly around 20 to 30 knots with gust of 35 kts (north) to
45 kts (south) this afternoon. Winds diminish a little and
shift more to the northwest, but it remains windy this evening,
especially over central ND, while winds do begin to drop off in
the far west.

&&

.BIS WATCHES/WARNINGS/ADVISORIES...
Wind Advisory from 10 AM CST /9 AM MST/ this morning to
midnight CST /11 PM MST/ tonight for NDZ040>044-061-062.

&&

$$

DISCUSSION...Hollan
AVIATION...TWH/Hollan