620
FXUS65 KBYZ 021741
AFDBYZ

Area Forecast Discussion...Updated
National Weather Service Billings MT
1041 AM MST Tue Dec 2 2025

.KEY MESSAGES...

- Weather system brings precipitation (rain/snow) and breezy winds
  to the area today into early Wednesday.

- Light snow accumulations possible over the lower elevations,
  with a few inches forecast over the higher hills and down along
  the mountains and foothills of southern Montana and northern
  Wyoming.

- Unsettled conditions continue Thursday into the weekend.

&&

.UPDATE...

Wet snow continues to slide southeast over northern and eastern
portions of the area this morning with area webcams showing
moderate to heavy snow in places. Raised snow amounts a bit over
the northeast given latest radar and guidance trends. As a result,
have added in Northern Rosebud, Treasure and Custer counties into
the Winter Weather Advisory through this evening. Greatest snow
amounts will generally be south of I-94 in these areas. The rest
of the forecast remains on track. STP

&&

.DISCUSSION...

Today through Monday...

A weather system will bring precipitation, breezy winds, and
colder temperatures to the area today into Wednesday morning. With
this, there will generally be two waves of precipitation. The
first, associated with an initial shortwave trough passage, is
already moving into the area this morning. This wave is bringing
snow to the western mountains, and is expected to bring rain/snow
to eastern Montana through the morning hours. While light
precipitation is possible over south-central Montana around and
west of Billings this morning (up to 30 percent chance), gusty
downslope winds will limit the amount of precipitation that makes
it to the ground. By this afternoon/evening into tonight, a cold
front associated with the main splitting trough will drop into and
through the region, turning winds more out of the north than
northwest. This will allow the second wave of precipitation to
develop and push south into the mountains and foothills, and
higher hills, of southern Montana and northern Wyoming. With this
second wave, unstable, upslope flow combined with pockets of
enhanced frontogenesis are expected to bring a decent period of
snow to the areas mentioned above this evening into early
Wednesday morning. While light snow looks to linger over the
mountains and foothills Wednesday morning, downslope winds are
expected to regain control by mid- day, ending any remaining
snowfall over the area.

With temperatures expected to climb into the 30s today,
precipitation may be a rain/snow mix over the lower elevations
during the day, as previously mentioned. However, precipitation
looks to remain all snow, albeit wet snow, over the higher hills.
As the colder air works in from the north this evening behind the
cold front passage, precipitation across the area is expected to
change over to snow. As far as snowfall amounts go, anywhere from
a dusting up to a few inches are forecast over the lower
elevation, with the greatest amounts over the north facing
slopes/hills of southern Montana and northern Wyoming. In the
mountains, anywhere from 5 to 10 inches are forecast, again with
the highest amounts over north facing slopes. Along with the snow,
breezy northerly wind gusts around 15 to 30 mph this evening and
night will likely produce some blowing snow as well, which could
further reduce visibility at times. Any wet or slushy surfaces
will also likely freeze this evening into tonight as air
temperatures drop into the teens to single digits. With this, the
Winter Weather Advisories in effect for portions of the southern
foothills into southeastern Montana, as well as the northern
Bighorn/Pryor Mountains, remain in good shape. The one other area
to watch today will be around the Bull Mountains where 1-2 inches
of snow are currently forecast, but higher amounts could be
realized if the unstable northern flow catches on to this area.

After the precipitation comes to an end Wednesday morning, dry
conditions looks to prevail with highs in the teens and 20s over
eastern Montana and 20s and 30s over south-central Montana and
northern Wyoming.

Persistent northwesterly flow through the rest of the week and
weekend look to keep the weather forecast active with occasional
chances of precipitation and wind, which could become strong at
times, especially over the foothills west of Billings. Look for
temperatures to oscillate back and forth from above, to near, to
below normal at times (20s and 40s) with each passing system. If
you have outdoor or travel plans later this week into this
weekend, make sure to stay up to date with the latest forecast.
Arends/STP

.AVIATION...

18z Discussion...

Snow showers continue across the forecast region and are predicted
to continue through 06z for most locations. As we head into the
overnight hours (after 00z) expect ceilings to lower into
MVFR/IFR range and continue through the remainder of the period.
KBIL/KSHR are forecast to see BKN015 CIGs. Gusty winds out of the
NW will continue for most of the period as well. Gusts at all
sites could reach 20kts with KLVM/K6S0 possibly reaching 30kts
before 00z. Mountains will be obscured for the entire period. WMR

&&

.PRELIMINARY POINT TEMP/POPS...

    Tdy Wed     Thu     Fri     Sat     Sun     Mon
-------------------------------------------------------
BIL 037 017/030 019/037 027/037 027/036 023/039 029/042
    6/S 61/B    00/B    33/S    55/O    31/B    10/N
LVM 037 017/035 021/039 026/040 029/042 026/043 028/045
    6/S 51/B    02/S    55/S    66/O    31/N    11/N
HDN 036 014/028 012/038 025/038 023/035 018/040 025/042
    9/O 81/B    01/B    54/O    66/O    41/B    11/B
MLS 035 009/019 011/035 025/033 019/029 014/035 024/039
    8/O 50/B    01/B    42/S    63/S    30/B    10/B
4BQ 037 013/023 015/036 026/035 022/033 021/037 027/041
    9/S 71/E    00/B    32/S    43/S    30/B    10/B
BHK 035 000/016 004/033 021/032 013/027 010/033 020/038
    5/S 40/B    00/Q    32/S    53/S    31/B    10/Q
SHR 037 015/029 013/040 023/038 021/038 018/042 022/044
    7/S 82/S    01/B    53/S    65/O    41/B    11/B

&&

.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...Winter Weather Advisory in effect until 11 PM MST this
      evening FOR ZONES 30>32.
     Winter Weather Advisory in effect until 5 AM MST Wednesday
      FOR ZONES 36-37-57-58-138-171.
     Winter Weather Advisory in effect from 5 PM this afternoon to
      5 AM MST Wednesday FOR ZONES 56-66-169.
WY...Winter Weather Advisory in effect until 5 AM MST Wednesday
      FOR ZONE 198.
     Winter Weather Advisory in effect from 5 PM this afternoon to
      5 AM MST Wednesday FOR ZONE 199.

&&

$$
weather.gov/billings