Alpine, Montana Weather Forecast Discussion

448
FXUS65 KBYZ 080810
AFDBYZ
Area Forecast Discussion
National Weather Service Billings MT
210 AM MDT Mon Sep 8 2025
.KEY MESSAGES...
- Above normal temperatures through first half of work week.
- Repeated late day isolated/scattered showers and storms Tuesday
  through Thursday.
- Good chance of significant precipitation and cooler temps by Friday.
- Persistent periods of wildfire smoke.
&&
.DISCUSSION...
Through Tuesday Night...
Upper ridge axis will be over our region today limiting any
upward forcing...and flow will remain westerly (downslope). Thus,
we should stay mostly dry except for a few isolated showers over
the high country. Temperatures will be in the 80s, about 4-8
degrees above our seasonal norms. Lows tonight will be in the 50s.
For Tuesday...large upper low off the west coast will exert some
impact into the Rockies as it slowly digs and comes ashore over
northern California. This will push the upper ridge axis over our
area to the east with our mid level flow strongly backing to
south/southwest and turning diffluent over our western zones by
Tuesday evening...all the while easterly low level flow (upslope)
is induced over eastern Montana. Models agree this will lead to
scattered showers and isolated thundershowers late Tuesday into
Tuesday evening, mainly over the mountains and western half of our
forecast area (west of Rosebud County). Progged MUCAPE and shear
is not impressive at this point, so we do not expect any strong
storms. High temps will still be well into the 80s for most
locations.
Smoke and haze will continue to affect our area for the next few
days, though models indicate near surface concentrations will not
be as dense as last week. Air quality will likely be impacted, and
folks sensitive to smoke are urged to take care and not spend to
much time outdoors. BT
Wednesday through Sunday...
Southwest flow associated with a West Coast trough will bring a
daily chance for showers and thunderstorms into the weekend. This
pattern looks to favor some strong to potentially severe
thunderstorms, for Wednesday and Thursday. Models continue to show
high CAPE values for this time of year, upwards of 1500 J/kg in
southeastern MT. Along with this, PWATs are forecast to be above 1
inch across the forecast area. While the pattern does look
favorable for stronger storms, it is too soon to determine the
finer details at this time. Continue to monitor the forecast as
the week progresses.
High temperatures will remain around to above normal, in the
upper 70s to around 90F (warmest around and east of Billings),
Wednesday and Thursday. The aforementioned trough is shown moving
into the Mountain West towards the end of the week, ensembles
depict an upper low forming over the Northern Rockies. This will
bring the continued chance for showers and thunderstorms, some of
which could bring heavy rainfall depending on the track of the low.
Matos
&&
.AVIATION...
VFR conditions will prevail through the forecast period. Although
reductions to surface visibility are not anticipated with
wildfire smoke, slant range visibility will likely be impacted
through today. Matos
&&
.PRELIMINARY POINT TEMP/POPS...
Tdy Tue     Wed     Thu     Fri     Sat     Sun
-------------------------------------------------------
BIL 086 055/086 057/087 058/084 057/076 056/069 053/074
    1/B 10/K    21/B    23/W    46/T    76/W    43/W
LVM 083 047/080 048/081 047/079 045/074 046/067 045/071
    1/U 13/T    33/T    44/T    46/T    66/T    43/T
HDN 087 051/088 055/089 055/086 054/077 054/070 048/075
    1/K 10/K    21/B    22/W    46/T    76/W    53/W
MLS 087 054/087 060/090 062/089 059/082 058/072 054/074
    0/K 10/K    21/B    21/B    34/T    77/W    53/W
4BQ 083 055/085 060/089 063/088 057/078 056/069 053/071
    0/K 00/K    11/B    11/B    24/T    76/T    43/W
BHK 087 050/084 054/085 059/088 055/082 053/074 051/073
    0/K 10/K    11/N    21/B    33/T    76/T    53/W
SHR 083 050/085 052/088 053/085 050/075 049/069 045/073
    1/U 11/K    21/B    22/W    36/T    77/T    53/W
&&
.BYZ WATCHES/WARNINGS/ADVISORIES...
MT...None.
WY...None.
&&
$$
weather.gov/billings

NWS BYZ Office Area Forecast Discussion