Area Forecast Discussion
Issued by NWS Billings, MT

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
521
FXUS65 KBYZ 101611
AFDBYZ

Area Forecast Discussion
National Weather Service Billings MT
911 AM MST Tue Dec 10 2019

.UPDATE...
NW flow aloft exists over the region this morning, with a 130 kt
H3 jet over eastern Montana. There remains some light snow in our
eastern cwa and it is in fact snowing at Miles City at 9 am. Have
expanded coverage of light snow today, but this will not amount
to much. Next clipper with surge of pressure rises will bring some
light snow to our far east tonight. Gusty SW-W winds and much
drier/warmer conditions will continue along our western foothills.
Gusts at Livingston will approach 60 mph tonight, and will need
to watch for a possible wind advisory for the gap areas. JKL

&&

.DISCUSSION...

Today through Wednesday Night...

Baroclinic band of snow has been slowly shifting east through the
night as anticipated thanks to upper ridge building to the west.
We will keep highlights in the Big Horn County area going a few
more hours, but anticipate cancelling it before the end time of
9AM.

Models set the band up over our eastern most zones early today.
The frontogenesis weakens as well, so we do not expect much more
than light snow or flurries with non-significant accumulation if
any. As the colder air is shunted east, our western and central
zones should warm up fairly well today with 30s to lower 40s, but
the east will only be in the 20s. In the meantime, winds in the
western foothills will be increasing.

For tonight, surface pressure gradient strengthens to our
southwest thanks to pressure falls on the plains. The orientation
will favor high winds in the Nye and Livingston areas. Gusts over
50 mph area a good bet and may push 60 mph at times. In our far
eastern zones, another push of cold air is progged to slide back
in, bringing another period of easterly winds and potentially some
light overrunning snow across Miles City, Baker and Ekalaka.
These areas could see around an inch or less of snow overnight
before dissipating by Wednesday morning.

For Wednesday, models agree in tracking a short wave trough
from northern Idaho southeast across our CWA. Moisture looks a
little shallow thanks to the downslope winds ahead of it. For now,
we expect snow showers over the high country developing, with
some flurries possible over the plains. However, we may need to
add low PoP`s a bit over the plains if the disturbance trends a
little stronger such as the newer GFS data suggest. This wave will
result in Livingston wind backing off a bit by Wednesday
afternoon. BT

Thursday through Monday...

Few changes were made to the forecast. Winds will remain elevated
throughout the end of the week with chances for light snow in the
lower elevations.

Thursday will remain unsettled with snow showers initially moving
over the mountains before shifting onto the lower elevations as a
disturbance moves southeast. Due to the above normal temps
Thursday afternoon, precip will initially fall as rain or a
rain/snow mix before transitioning to snow in the evening and
overnight. The mountains could see multiple inches of snow while
the lower elevations will be light accumulations. Winds will also
be sub-advisory throughout Thursday and Thursday night.

A backdoor front will slide into the region late Friday bringing a
chance for showers to the western half of our CWA. Temps will cool
with this front allowing for most precip to fall as snow. The best
chance for snow will be along the foothills due to upslope but
specific detail and uncertain this far out. Winds will remain near
subadvisory criteria for the Livingston/Big Timber area before
decreasing as the front moves in. The front will continue to
impact southeastern Montana through the weekend before shifting
east towards the ND border. Winds will increase along
Livingston/Nye/Big Timber as the front moves out but the strength
is uncertain at this time.

High temps will be warmest on Thursday with temps in the upper 30s
and lower 40s before cooling into the low to mid 30s. Expect near
normal temps through Monday next week. Carrothers

&&

.AVIATION...

Areas of light snow will impact eastern areas near KMLS, KBHK and
K97M today and tonight...bringing periodic MVFR to IFR flight
conditions. VFR will prevail to the west, though mountains may be
periodically obscured in light snow showers. Gusty SW-W winds will
impact the western foothills. Gusts to 35 kts at KLVM today will
increase to 45 kts tonight. JKL

&&

.PRELIMINARY POINT TEMP/POPS...

    Tdy Wed     Thu     Fri     Sat     Sun     Mon
-------------------------------------------------------
BIL 038 023/041 026/045 031/044 023/035 021/034 020/036
    0/E 01/E    01/B    33/O    32/S    22/S    11/B
LVM 039 026/041 027/044 030/040 023/033 018/030 016/032
    0/N 02/S    05/O    55/O    43/S    22/S    11/N
HDN 038 017/040 020/044 027/044 019/034 015/034 015/037
    1/E 01/E    01/B    33/O    43/S    21/E    11/B
MLS 031 014/034 018/042 029/037 015/026 015/030 018/035
    2/S 21/E    01/B    12/O    21/E    11/E    10/B
4BQ 032 014/036 020/040 027/040 018/029 014/030 016/033
    2/S 11/E    01/B    22/O    21/E    11/E    00/B
BHK 025 008/027 015/038 025/034 010/023 011/027 015/031
    3/S 41/E    10/B    12/S    21/E    01/E    00/B
SHR 037 017/041 018/045 024/042 018/033 014/031 010/036
    2/S 01/E    01/B    34/O    32/S    22/S    11/U

&&

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

&&

$$
weather.gov/billings



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.