000
FXUS65 KBYZ 191931
AFDBYZ

Area Forecast Discussion
National Weather Service Billings MT
131 PM MDT Fri Apr 19 2024

.DISCUSSION...

Through Saturday night...

Satellite imagery shows cyclonic NW flow remaining over the
region, though we are starting to see height rises as parent upper
low continues to move eastward. Weak ascent with shallow/moist
instability continues to be enough for areas of light snow and
flurries east of Billings (as far west as eastern Musselshell and
northeast Big Horn Counties per current radar imagery). Further
west, including at Billings, the flat cumulus fields are
indicative of the rising heights and drying. Cannot rule out a few
snow showers over the mountains, otherwise, any chance of precip
in our forecast area should end by sunset.

Surface analysis shows a healthy-for-April 1036mb high over north
central MT. This high will sag slowly to the southeast and weaken
over the next 24 hours. This will result in: (1) light winds and
chilly temps tonight, with lows more likely to reach the teens
where there is clearing; (2) a slow warmup tomorrow as despite the
upper level ridging, low level easterly flow associated with the
surface high will persist. Daily record low of 19F at Miles City
on the 20th will be challenged. Look for temps on Saturday to
reach the 40s to lower 50s...still several degrees cooler than
normal. Saturday night will be a milder night, and still dry
underneath the ridge, with lows in the 20s to lower 30s. Downslope
gradients will develop along the western foothills late tomorrow
night, but winds should stay modest until later on Sunday.

JKL

Sunday through Friday...

Sunday will see dry southerly winds ahead of the low pressure
system working its way out of southern Canada. This will lead to
RH values in the lower 20s for locations from Sheridan County up
to Rosebud County and locations to the east. Temperatures during
this time will be in the mid 60s to low 70s with breezy winds
gusting into the 20s mph. Due to soil conditions, recent
precipitation and lack of strong winds, there are no fire concerns
at this time.

Winds will pick up along with precipitation chances as the cold
front moves through from west to east. Winds behind the front will
be strong out of the northwest with winds gusting into the 30s and
40s mph across the region. Precipitation chances have generally
come down with most of the region now having a 50% chance of
seeing rain. After the front moves through we pass through a dry
slot before the low starts to drop down and bring more moisture,
renewing precipitation chances for Monday. The chance for
precipitation from the second round will only be around 25%.
Overall precipitation from this system looks to remain light with
locations west of Colstrip having a 20-40% chance of seeing >.10
inches of precipitation. Locations to the east will have a <20%
chance. Temperatures will be cooler Monday with temperatures in
the mid to 50s.

After the passage of the upper low, we will move into more of a
ridging/downsloping pattern with most of the region having a good
chance (60-80%) of getting over 70F by Wednesday. Towards the end
of next week, ensembles are pointing towards a pattern shift with
a low pressure system off the Pacific coast putting southeast
Montana into southwest flow bringing back precipitation chances.
This would also act to lower temperatures back into the 60s for
most Thursday and Friday. Torgerson

&&

.AVIATION...

Isolated light snow showers/flurries will produce localized MVFR
east of KBIL until around 01z. VFR will prevail elsewhere through
the remainder of the day, while mountains are occasionally
obscured in light snow showers. Building high pressure will bring
a transition to widespread VFR tonight. Breezy NW winds will
impact sites east of KBIL through sunset, with 20-30 knot gusts.
Winds will become light this evening.

On Saturday, look for high pressure aloft, widespread VFR and
light winds across the region.

JKL

&&

.PRELIMINARY POINT TEMP/POPS...

    Sat     Sun     Mon     Tue     Wed     Thu     Fri
-----------------------------------------------------------
BIL 024/050 030/067 038/060 036/062 039/072 046/068 045/065
    00/U    01/B    51/N    00/U    01/B    25/R    35/R
LVM 020/049 030/066 031/056 030/061 036/069 042/065 041/060
    10/U    02/R    21/N    00/U    02/R    35/R    46/R
HDN 020/051 026/070 037/062 035/064 036/075 044/072 043/067
    00/U    01/B    61/N    10/U    01/B    24/R    45/R
MLS 021/048 026/068 039/057 035/059 038/071 044/069 044/066
    00/U    00/B    31/N    00/B    00/B    12/R    23/R
4BQ 020/048 026/071 039/058 036/059 039/072 045/070 045/065
    00/U    00/U    21/N    10/U    00/B    12/R    33/R
BHK 018/046 024/065 036/055 033/057 034/067 041/065 038/062
    00/U    00/U    32/R    11/B    00/B    12/R    33/R
SHR 016/048 022/068 034/057 032/060 034/071 041/068 041/063
    10/U    00/B    42/R    10/U    01/B    25/R    55/R

&&

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

&&

$$
weather.gov/billings