000
FXUS65 KBYZ 181528
AFDBYZ

Area Forecast Discussion
National Weather Service Billings MT
928 AM MDT Thu Apr 18 2024

.UPDATE...
Chilly cyclonic flow will remain over the region today. Morning
band of light snow showers over our east have dissipated, but we
are already starting to see cumulus fields develop with daytime
heating. Though the boundary layer will be quite dry, there should
be enough shallow instability for afternoon and evening light
snow showers/flurries mainly from Billings westward and southward.
Mountains will pick up minor snow accumulation with the snow
showers. Look for highs today mostly upper 30s to mid 40s.
Forecast is in good shape. JKL

&&

.DISCUSSION...

Today through Friday night...

Isolated to scattered snow showers along the southern mountains
and foothills and over northern portions of the area will
gradually decrease into the morning hours. Additional snow
accumulations will generally be an inch or less. Have gone ahead
and canceled the Winter Storm Warning for the Bighorn Mountains.

Cool, cyclonic north to northwest flow looks to remain over the
area through Friday. Instability and upslope flow into the
mountains and foothills will keep rain/snow showers in the
forecast. While a few showers are possible out onto the lower
elevations generally west of Billings, the greatest shower
coverage will be over the mountains and adjacent foothills (20-40%
chance). Snow accumulations are expected to be light. Gusty
northwest winds will continue today as well, highest east of
Billings, where wind gusts of 25-40 mph can be expected. Along
with the northwest winds, afternoon RH will drop into the 20s for
many locations. High temperatures will range from the upper 30s to
middle 40s today, a good 10-15 degrees below normal.

Friday will see similar conditions to today, although winds and
temperatures will be a bit lower. Highs will range from the middle
30s to lower 40s. Winds will turn more north to northeasterly
over central and western areas, with northwest winds continuing to
prevail over the far east, where gusts to 35 mph remain possible.
Make sure to protect tender vegitation with low temperatures in
the teens and 20s the next several nights. STP

Saturday through Thursday...

Upper ridging will be over the forecast area Saturday through Sat.
night with dry weather. High temps will remain below normal in the
mid 40s to lower 50s. Chances for rain showers will increase from
W to E across the area Sunday through Sun. evening with a slight
chance of thunder W of KBIL, as a cold front pushes E through the
area Sun. afternoon and evening. Front will be associated with an
upper low that will move ESE along the MT/Canadian border Sunday
through Mon. evening. Models differed on the position and speed of
this low which added uncertainty to the forecast. Chances for
mainly rain showers will continue through Monday. As of now, the
best period for precipitation was Sun. evening with 40-60% chances
over most of the area. As for QPF, there was a 10-20% chance of at
least a quarter inch of precipitation from 00Z Mon-00Z Tuesday.
Chances for half an inch of QPF were extremely low. High temps
will rebound into the 60s on Sunday and will be a few degrees
cooler behind the front on Monday. Expect windy conditions behind
the front for Monday.

Upper ridging moves across the area Tuesday and Wednesday, before
the next Pacific trough approaches the region for Thursday. There
were model differences in the handling of the trough. It will be
warmer and dry on Tuesday, then a 20-30% chance of showers and
thunderstorms will move E into the area Wed. afternoon. Highs will
be mainly in the 70s on Wednesday. Low chances for showers
continue into Thursday, then PoPs increase (30-50%) for showers
and thunderstorms Thu. afternoon. Due to model differences with
the trough, will need to keep an eye on future model trends.
Arthur

&&

.AVIATION...

Isolated snow showers and flurries will impact the region this
afternoon and evening. VFR will prevail, but cannot rule out local
MVFR especially close to the foothills, and the mountains will be
obscured at times. NW winds will be brisk today, with gusts of
25-40 knots, greatest east of KBIL. JKL

&&

.PRELIMINARY POINT TEMP/POPS...

    Tdy Fri     Sat     Sun     Mon     Tue     Wed
-------------------------------------------------------
BIL 046 025/043 024/050 031/064 038/060 035/065 040/072
    1/M 10/B    00/U    03/W    52/W    00/U    12/W
LVM 044 021/042 020/050 032/061 033/057 031/063 038/069
    1/M 10/B    00/U    04/T    41/U    00/B    13/T
HDN 048 023/044 021/053 027/067 037/060 033/068 040/076
    1/B 00/B    00/U    02/W    63/W    00/U    12/W
MLS 044 023/040 021/047 027/064 039/057 034/063 040/072
    0/N 00/B    00/U    01/B    43/W    00/U    11/B
4BQ 044 021/040 020/048 028/067 039/057 033/063 040/074
    0/N 00/B    00/U    00/B    43/W    00/B    11/B
BHK 041 019/037 018/046 023/061 036/053 031/059 035/067
    0/N 00/N    00/U    00/U    44/W    10/B    11/B
SHR 043 018/041 017/049 025/065 034/057 029/064 037/072
    1/M 11/B    10/U    01/B    53/W    10/U    12/W

&&

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

&&

$$
weather.gov/billings