459
FXUS65 KBYZ 140609
AFDBYZ

Area Forecast Discussion
National Weather Service Billings MT
1209 AM MDT Sat Sep 14 2024

.DISCUSSION...
Through Saturday night...

Isolated showers continued across the northern tier of the
forecast area this afternoon, with a few showers over the SW
mountains. Tweaked afternoon PoPs toward the GFS which had a good
handle on the location of the precipitation. Pieces of energy were
moving through the cyclonic flow on the S side of the upper low
which was over Saskatchewan this afternoon. The showers were
occurring with the best moisture, where PWAT`s were around 0.7
inches. GFS kept a slight chance of showers over far northern
Custer and Fallon Counties through 03Z, so included this in the
forecast. Otherwise, there will be some smoke and haze in the
vicinity of the Short Draw Fire over far southern portions of the
area tonight. Cancelled the Winter Weather Advisory early for the
Beartooth Highway as the snow had ended. Be sure to check road
conditions before heading into the mountains.

W flow on Saturday will become SW Saturday night ahead of the next
trough along the Pacific NW coast. It will be dry Sat. and Sat.
night with temps in the mid 70s W to mid 80s SE on Saturday.
Humidities will be in the teens over lower elevations of Sheridan
County and along the S edge of SE MT, but it not be windy in these
areas for fire weather concerns. Nudged wind speeds up a bit
toward the NBM 90th percentile W of KBIL and over Fallon and
Carter Counties based on signals from the ECMWF ensemble
meteograms. Arthur

Sunday through Friday...

Heights build over the area on Sunday, in response to troughing
over the West Coast. Warm and dry conditions will prevail with
highs in the 80s, perhaps near 90 degrees over the east, and
minimum relative humidity values in the teens and 20s. Winds look
light overall. Precipitation chances move back into western areas
Monday, as an upper low is progged to move into the Great Basin.
Ensembles eventually have the area of low pressure lifting into
the Northern Rockies Tuesday into Tuesday night, bringing
increasing shower and thunderstorm chances (40-80%). Some snow
accumulation looks possible in the mountains above 9,000 feet as
well. Shortwave ridging on Wednesday then looks to be replaced by
another potential area of low pressure moving into the region for
Thursday and Friday, keeping generally cool conditions in place.

High temperatures in the 70s west, to the 80s east on Monday and
Tuesday, are forecast to lower into the 60s and 70s for Wednesday
and Thursday. STP

&&

.AVIATION...

Look for widespread VFR through the period, under a dry westerly
flow aloft. JKL

&&

.PRELIMINARY POINT TEMP/POPS...

    Sat     Sun     Mon     Tue     Wed     Thu     Fri
-----------------------------------------------------------
BIL 047/078 049/084 054/082 054/075 050/073 048/069 047/070
    00/B    00/U    11/B    46/T    51/B    12/W    33/W
LVM 040/077 043/082 047/078 046/067 042/065 041/065 040/067
    00/B    00/B    24/T    88/T    74/W    24/W    34/W
HDN 044/080 046/089 051/084 053/079 047/075 046/070 046/070
    00/B    00/U    00/B    35/W    41/U    12/W    33/W
MLS 046/079 049/086 059/087 059/082 052/073 049/070 048/069
    00/B    00/U    01/U    23/W    51/U    11/B    33/W
4BQ 045/083 049/089 060/089 060/084 051/075 049/072 049/068
    00/B    00/U    00/U    12/W    31/U    12/W    33/W
BHK 046/083 048/088 057/087 057/085 050/075 047/072 046/071
    00/U    00/U    11/U    13/W    41/U    12/W    33/W
SHR 040/080 045/089 051/086 051/080 043/075 043/071 042/068
    00/U    00/U    00/B    23/W    31/U    13/W    44/W

&&

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

&&

$$
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