599
FXUS63 KBIS 180407
AFDBIS

Area Forecast Discussion
National Weather Service Bismarck ND
1007 PM CST Mon Nov 17 2025

.KEY MESSAGES...

- On and off low to medium chances for light rain tonight
  through Wednesday night, with a 20 percent chance of light
  freezing rain in central North Dakota tonight.

- Patchy fog in the far southwest late tonight into Tuesday
  morning.

- Near to above normal temperatures this week, with highs each
  day mostly in the upper 30s to lower 50s.

- Colder temperatures and above normal precipitation are favored
  for the last week of November.

&&

.UPDATE...
Issued at 944 PM CST Mon Nov 17 2025

Isolated to scattered light rain continues across much of
central ND this evening. The main show is definitely with the
system moving across South Dakota into southern Minnesota. Over
North Dakota we have weak high pressure at the surface and High
pressure aloft. There is just enough weak warm advection
combined with a weak shortwave moving through the shortwave
ridge, congruent with abundant moisture to keep light rain
showers continuing. Surface temperatures are generally in the
middle 30s with dewpoints mainly in the 20s so we can`t rule out
a low probability of some light freezing rain, and this has been
advertised. Rain amounts should be light and with abundant cloud
cover, forecast soundings, if they do drop below freezing, only
drop below freezing for a short period of time. At this time
think any impacts from freezing precip would be minimal.
Certainly will continue to monitor. Just some minor updates to
pops based on latest radar. Cams are not really picking up on
the light precip so blended to previous forecast guidance.

UPDATE
Issued at 602 PM CST Mon Nov 17 2025

Made some minor adjustments to pops/sky cover based on latest
radar and satellite analysis. Otherwise no changes needed to the
going forecast.

&&

.DISCUSSION...
Issued at 200 PM CST Mon Nov 17 2025

Split flow is found over North Dakota today as a stacked upper
level low crosses from east to west across SD/NE. Scattered
precipitation can be found across western and central North
Dakota this afternoon and evening as mid level warm air
advection and isentropic ascent ticks up to the north of the
low, all the while moisture streams in from the southeast. The
highest chances for precipitation (20 to 40 percent) remains
along an axis draped roughly from New Town to Jamestown through
this afternoon, and is anticipated to fall mainly as rain
throughout this period. That begin said, there is also a low (10
to 20 percent) potential for some freezing drizzle/rain along
the northernmost edge of this precipitation if it lingers into
the mid to late evening. In this circumstance, a light glaze of
ice is not impossible over portions of north central North
Dakota, mainly on elevated surfaces. Overall precipitation
totals through tonight are anticipated to be fairly light, with
a few hundreths QPF advertised by the ensemble. The highest
potential for measurable QPF is found to the north of Lake
Sakakawea, where slightly better forcing is progged to develop
in the late afternoon and evening. Otherwise, persistant cloud
cover across the forecast area and highs broadly in the 40s are
expected today, with some upper 30s possible in the Turtle
Mountains and James River Valley.

The bulk of synoptic forcing is anticipated to diminish this
evening as the aforementioned stack low exits east toward the
Great Lakes Region overnight. That being said, another round of
low PoPs is anticipated overnight as a transient and weak
shortwave traverses through the near zonal flow found over the
region. Despite a general cooler column, a potential warm nose
aloft due to ongoing WAA indicates that more freezing
drizzle/rain is again possible during this period, mainly in the
Turtle Mountains region, though comparably dry conditions is
anticipated to minimize ice accumulations. Otherwise, for
tonight, patchy fog is possible in the far southwest as winds
die out and cloud cover begins to diminish.

Mainly dry conditions are then anticipated through the day
Tuesday as transient ridging sweeps through the northern Plains.
Cloud cover somewhat diminishes through this period, though
only becoming partly to mostly cloudy before a reinforcing
northern stream wave starts to push across the southern Canadian
Prairies in the late afternoon, early evening. With this, light
precipitation is also possible during this period, with low
chances (10 to 20 percent) spreading from the southwest across
central North Dakota Tuesday evening through Wendesday night.
That being said, interrogation of model soundings during this
period reveal a fairly warm column and dry near surface
conditions, indicating that fairly low amounts of mainly liquid
precipitation is anticipated to reach the ground by the time
synoptic forcing diminishes Wednesday night. Portions of north
central North Dakota may see some limited wintry-mixed
precipitation by the time precipitation diminishes Wednesday
night. Overall impacts associated with this wave are anticipated
to be low at this time. Otherwise, high temperatures both
Tuesday and Wendesday are forecast to be slightly warmer, from
the lower 40s north central to the lower to mid 50s southwest.

Slightly cooler conditions are then on the docket Thursday as a
cooler air mass settles over the northern Plains, with morning
lows from the lower 20s west to lower 30s southeast and
afternoon highs broadly in the 40s. The ensemble becomes
increasingly discordant through beyond this timeframe, as model
members attempt to reconcile the timing and northward
displacement of an another upper level Pacific low through the
second half of the workweek. Cluster analysis reveals two broad
scenarios at the time of this forecast cycle. A slight majority
(45 percent of members) favor a near zonal flow regime as the
aforementioned low remains far the south, which would keep the
northern Plains near to slightly above normal temperatures for
this time of year. This scenario would also be the drier of the
two in the long term, though transient shortwaves could induce
brief low to medium PoPs over portions of the forecast area. A
minority cluster also exists (35 percent of available model
members), which instead favors a split flow regime persisting
through the weekend as the low slowly meanders north. Highs
throughout this period would be near normal, and with some
potential for precipitation near the end of the week/early next
week as the low approaches the forecast area. Beyond this
period, however, long term guidance leans toward near to below
normal temperatures and above normal precipitation through the
end of the month.

&&

.AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/...
Issued at 944 PM CST Mon Nov 17 2025

VFR conditions to begin the 06Z TAF period and VFR conditions
expected through much of the period at all TAF sites.

Low pressure over the central and southern portions of the
Northern Plains will track east overnight. North Dakota will
remain mostly cloudy through the period but most of the
precipitation will remain south of the ND Border. There is an
area of light rain showers over central ND that will move little
overnight and may change over to mixed precipitation with
mostly a rain snow mix. However there is a small chance (20%)
that some light freezing rain could mix in with the
precipitation. Ceilings are currently forecast to remain VFR
through the period at KXWA, KMOT and KJMS. KDIK and KBIS are
showing low to medium probabilities (20-40 percent) for MVFR
ceilings Tuesday morning. KDIK could also see some patchy fog
late tonight into Tuesday morning. Easterly surface flow
5-15kts will shift southerly by Tuesday morning at all TAF
sites.

&&

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

&&

$$

UPDATE...TWH
DISCUSSION...Adam
AVIATION...TWH