Area Forecast Discussion
Issued by NWS Billings, MT

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717
FXUS65 KBYZ 310740
AFDBYZ

Area Forecast Discussion
National Weather Service Billings MT
140 AM MDT Fri May 31 2024

.DISCUSSION...

Today through Saturday...

Satellite imagery shows broad cyclonic flow with a shortwave and
cooling cloud tops over south central MT, while upper air analysis
shows a 70-80kt H3 jet diving from the Canadian Rockies into
northwest MT. Per the ascent we are seeing showers increase in
coverage over the Beartooth-Absarokas and approach the Pryor
Mountains. Light shower activity will slowly spread eastward thru
the morning, staying south of Billings. Snow levels are around
7kft so some light accumulation is expected over the high
elevations (less than 1"). As the wave tracks to the east there
will be a hint of theta-e return in far southeast MT, with perhaps
enough instability for isolated showers and weak thunderstorms
from Miles City to Broadus eastward this afternoon and early
evening. CAMs are very modest here so do not expect much activity.
Behind the wave we will see mixed west winds gusting 15-25 mph
(not as strong as on Thursday). After a chilly start, temps will
warm to the mid 60s to lower 70s. Speaking of temps, it is already
in the mid 30s from Livingston to Harlowton so expect localized
frost in our west.

Building flat ridge will bring dry conditions late tonight through
mid afternoon Saturday. By late tomorrow afternoon we will begin
to see convective potential increase in south central MT (i.e. our
western mountains) due to an approaching Pacific shortwave in the
zonal flow aloft. Pwats will gradually increase tomorrow, to near
0.75", resulting in late day sbcapes of 250-750 j/kg along the
foothills. Temps will be warmer tomorrow with highs in the mid 70s
to around 80F.

JKL

Saturday Night through Friday...

Models depict a weak trof or shortwave energy passing through MT,
Saturday night into Sunday morning. Chances for precipitation will
increase from west to east. PoPs will range from 15-50% with the
highest chance of showers in the western areas and the lowest
chance for showers in the east. A thunderstorm or two is possible
as well, with the strongest of any storms producing heavy rain.
A deeper and stronger trough approaches from the NW Sunday
afternoon/evening, swinging a cold front through the state. Higher
chances for precipitation will accompany this cold front. Models
are in disagreement with the extent of this front, with some
moving it through the region by Monday night and others not until
Tuesday morning. Regardless, there is a 15-70% chance of showers,
with higher chances in the west and lowest in the east. There is
more instability present ahead of this system which will result in
better chances for thunder.

In the wake of the departing cold front, increased winds and gusty
conditions are possible for most of Tuesday, with winds gusting
in the 20-40s mph. Ridging will begin building Tuesday as well,
persisting into the weekend. As a result, drier and warm
conditions are anticipated with the chance of precipitation being
negligible (>15%).

High temperatures in the 70s on Sunday and 70s-80s Monday. Tuesday
will cool down a bit with the frontal passage with temps in the
70s. Wednesday through Friday will see temperatures climb into the
upper 70s to mid 80s with upper ridging and dry conditions.

Matos

&&

.AVIATION...

Isolated early morning light showers south of KLVM-KBIL will
gradually spread to the east. By this afternoon, activity will be
from KMLS-K00F eastward, and cannot rule out a few weak
thunderstorms near the Dakotas border until ~01Z. VFR will prevail
at lower elevations, while mountains will be occasionally
obscured in the morning. Building high pressure will bring
clearing skies tonight. JKL

&&

.PRELIMINARY POINT TEMP/POPS...

    Tdy Sat     Sun     Mon     Tue     Wed     Thu
-------------------------------------------------------
BIL 069 044/078 053/074 054/079 052/070 052/082 055/083
    0/U 00/U    33/T    01/E    63/W    00/U    00/U
LVM 069 039/078 049/072 051/073 044/067 047/079 051/084
    0/U 01/B    35/T    04/T    72/W    00/N    00/U
HDN 070 042/080 051/075 052/082 051/073 049/083 052/085
    1/B 00/U    33/W    01/E    63/W    10/U    00/U
MLS 069 042/078 053/076 051/083 053/071 051/080 052/084
    2/W 00/U    22/T    01/B    62/W    10/U    00/U
4BQ 067 043/079 052/075 051/084 052/071 051/079 052/084
    2/W 00/U    12/T    00/B    42/W    10/U    00/U
BHK 067 041/077 051/074 048/080 051/070 047/075 047/079
    2/T 10/U    23/T    01/B    52/W    10/N    00/U
SHR 070 039/080 048/072 048/082 049/070 047/081 051/083
    2/W 00/U    13/T    00/B    54/T    00/U    00/U

&&

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

&&

$$
weather.gov/billings