Area Forecast Discussion
Issued by NWS Billings, MT

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
FXUS65 KBYZ 211027

Area Forecast Discussion
National Weather Service Billings MT
327 AM MST Sat Jan 21 2017

.SHORT TERM...valid for Tdy and Sun...

Skies generally clearing overnight and many locations that
received precipitation yesterday have narrow dewpoint
depressions. Therefore, we have increased the areal coverage of
fog for the morning hours with this package. Due to reports of
dense fog from Miles City and Forsyth already, will also issue
Dense Fog Advisory for much of southeast and central zones
including Billings through 10 AM.

Otherwise, a rather benign weak flow pattern across the region
today with 500 MB heights building over the area through the
weekend. We don`t expect much change in temps today into Sunday
though as we do not anticipate much mixing. Upper flow backs to
the southwest by tonight so some Pacific moisture works into the
Absarokas producing scattered snow showers.

A weak impulse in that Pacific flow rides into our CWA by Sunday
evening. So we may see a little precipitation spread beyond the
Absarokas into the rest of our west. However, this looks of little
consequence with dry low levels so we kept PoP`s low for lower
elevations in the west. BT

.LONG TERM...valid for Mon...Tue...Wed...Thu...Fri...

Last couple runs of the ECMWF have come more into agreement with
the GFS and CMC, developing the low further north over central
Wyoming which slides eastward into the Dakotas on Tuesday.
Expecting solid upslope flow Monday night into Tuesday morning.
GEFS mean and latest GFS runs have brought the qpf down a bit,
therefore adjusted the snow totals down an inch or so in most
places from Monday through Tuesday. Given the orientation of the
low-level flow and the position of the low did bump up snow totals
from the Red Lodge Foothills to Park City during the overnight
period on Monday. Still a pretty good spread among the ensemble
members for the snow amounts from Billings north and eastward, but
at the very least expecting accumulating snow for most of the
area Monday night through Tuesday.

Northwesterly flow continues through much of the week. Wednesday
morning is looking like the coldest period at this point with
temperatures in the single digits likely. No significant precip
at the end of the extended, but gusty winds look possible from
Big Timber to Billings as we head into the weekend. Walsh



Freezing fog has already developed at MLS and will continue
through the early morning hours. At Billings, vicinity dense fog
has begun and will likely move to the airport by 11z. Decent
chance at seeing tempo CIGS and VIS below airport minimums at
Billings as the fog continues to thicken. Fog clears up by late
morning and VFR conditions will prevail. Walsh



    Tdy Sun     Mon     Tue     Wed     Thu     Fri
BIL 034 021/032 018/028 018/025 008/024 013/028 018/030
    0/F 00/U    12/S    76/S    22/S    21/B    11/N
LVM 037 019/038 018/034 014/026 006/026 010/026 015/031
    1/B 21/U    24/S    75/S    22/S    21/N    11/N
HDN 031 011/030 009/026 013/024 004/022 007/025 011/028
    0/B 00/U    02/S    76/S    22/S    21/B    11/N
MLS 030 015/028 009/025 014/023 004/020 006/023 010/026
    0/F 00/B    01/B    54/S    22/S    21/B    11/B
4BQ 034 014/032 006/027 012/024 003/021 006/024 011/028
    0/B 00/U    02/S    77/S    32/S    22/S    11/B
BHK 030 014/027 008/024 013/022 004/018 005/021 008/026
    0/F 00/B    01/B    55/S    22/S    22/S    11/N
SHR 034 011/034 011/030 012/022 002/022 006/026 010/031
    0/B 00/U    02/S    77/S    22/S    21/B    11/B


MT...Dense Fog Advisory in effect until 10 AM MST this morning FOR
      ZONES 30>33-35-37.


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