852
FXUS65 KBYZ 251955
AFDBYZ

Area Forecast Discussion
National Weather Service Billings MT
1255 PM MST Tue Nov 25 2025

.KEY MESSAGES...

- Near to below normal temperatures Tuesday through Friday.
  Periods of light rain/snow possible (20-50%) this evening
  through Friday.

- Even colder air arrives Friday night with the potential for the
  first significant snowfall of the season across the area
  through Sunday. Stay tuned if you have Holiday weekend travel
  plans!

- Another round of winter weather is possible next week, stay
  tuned!


&&

.DISCUSSION...
Now through Tuesday...

The long awaited winter weather is at our doorstep just in time
for the Thanksgiving holiday. Over the coming 24-72 hours a
classic Hudson Bay upper level low will settle into place which
will dominate the upper level pattern over North America for the
next week. The first of these shots of winter weather will come
during the day tomorrow (Wednesday). A quick hitting clipper
system will dive out of the Canadian Rockies down the front range
and bring chances for a couple inches of mountain snowfall. While
it does appear likely that a few flakes will fall as far away as
Billings, the only accumulation that seems possible would be a
dusting on some grassy surfaces. Regardless, any snow could
potentially have impacts on one of the busiest travel days of the
year. Be sure to stay up to date on the weather if you are
traveling tomorrow, esepcailly if that involves driving through
mountain passes.

Thanksgiving should be a mostly benign day. Some light snow
showers and/or flurries are possible in the mountains and
foothills, however, minimal to no accumulation is expected.
Average temperatures are forecast region-wide with a high around
40F for Billings.

Friday a much more potent and deeper trough starts to move into
the region. This system may have PWAT values over 150% of normal
for this time of year possibly exceeding 0.5". This will likely
be the first widespread snow accumulation for the entire CWA. It
does not appear that there will be any particularly heavy
snowfall rates, however, a prolonged period of snow should allow
for at least a couple inches to accumulate. Ahead of the FROPA
there should be a light easterly surface flow that makes it into
into the foothills of south-central MT. This will allow for that
moisture return and colder air be an aid to some upslope
enhancement of the early snowfall. As the front moves in from NW
to SE during the day Friday, the moisture in place should be able
to be fully tapped into before the cP airmass dominates the
region. Moving into Saturday, as the surface low slowly pushes
out of the region, it appears that eastern MT/WY will end up
under a coupled jet. The larger of the jet streaks will be moving
out over the plains putting us under the right-entrance region as
a weaker, and meridional, jet dives south along the front range
of the Canadian Rockies putting our CWA under that left-exit
region. Following this, there could be several smaller forcing
mechanisms around the area through Sunday bringing continued
chances for light snow.

As of right now, it appears that there is a 50% chance that areas
near Billings receive at least 3" through Saturday night with
higher probabilities as you move into the foothills. Farther east,
in the plains, there should be lighter snowfall rates as this
will be farther removed from the upper level feature, however,
there is still a 30-40% chance of 3"+.

Moving into early next week, there is a good signal of yet another
trough digging into western North America. Ensembles are starting
to show a signal for potentially more accumulating snow in the
Monday-Wednesday timeframe, however, it is still too early to talk
specifics; esepcailly since we have yet to see the first longwave
trough push through. WMR

.AVIATION...

18z Discussion...

MFVR CIGs will linger around KMLS/KBHK over the next few hours
with no precip or CIG reductions expected. Winds throughout the
period should remain light with KBIL winds out of the SW at 10kts.
After 06z SHSN will move into the mountains of south-central MT
before impacting KLVM/K6S0 after 08z. MVFR CIGs and VIS can be
expected with this snow and an occasional dip to IFR is possible.

Around 15z SHSN will move towards KBIL where MVFR conditions
should be expected. At the same time snow should start in the
mountains above KSHR. Partial to full mountain obscuration is
expected for the entire period. WMR
&&

.PRELIMINARY POINT TEMP/POPS...

    Wed     Thu     Fri     Sat     Sun     Mon     Tue
-----------------------------------------------------------
BIL 026/041 026/040 026/031 010/022 008/024 014/032 021/038
    15/S    01/E    48/S    52/S    21/B    11/B    13/S
LVM 025/044 027/046 025/034 009/029 010/030 016/036 025/041
    46/O    22/O    48/O    42/S    21/B    11/B    24/S
HDN 021/040 023/042 025/032 009/023 004/024 008/032 016/039
    15/O    11/E    48/S    73/S    32/S    22/S    23/O
MLS 019/035 019/035 024/029 010/018 001/019 006/025 013/035
    02/S    00/B    45/S    51/E    11/B    11/E    22/S
4BQ 019/036 021/039 025/032 013/020 006/022 010/028 017/038
    02/S    00/B    25/S    52/S    11/B    11/B    12/S
BHK 011/035 013/034 018/028 006/017 902/017 001/024 009/034
    01/E    00/B    25/S    51/E    11/B    11/B    12/S
SHR 016/037 021/041 020/034 006/022 004/025 007/033 014/041
    03/S    20/E    27/S    73/S    32/S    22/S    13/O

&&

.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...None.
WY...None.

&&

$$
weather.gov/billings