236
FXUS65 KBYZ 180805
AFDBYZ

Area Forecast Discussion
National Weather Service Billings MT
205 AM MDT Mon Aug 18 2025

.KEY MESSAGES...

- Hot and dry conditions will continue through Wednesday.

- Temperatures by Tuesday and Wednesday could push 100 degrees
  with record highs possible.

- This stretch of warm and dry weather will bring an increased
  risk for wildfires. Take care to avoid causing a spark!

- Cold front will bring a return to seasonable, to slightly below
  normal temperatures Thursday into the end of the week.


&&

.DISCUSSION...

Today through Tuesday night...

A drier and warmer pattern begins today as upper level ridging
builds in over the region.

Today, a disturbance moving through the flow coupled with
lingering moisture (PWATs around 100-120% of normal) will allow a
small chance (10-30%) for showers and thunderstorms to develop
over the western mountains this afternoon. There is lower
confidence in storms maintaining themselves past the foothills
(<20% chance), given the lack of instability over the plains
(MUCAPE 250-750 J/kg).

Tuesday will then be hot and dry under mostly clear skies as the
ridge strengthens. Highs will climb from upper 80s to mid 90s on
Monday to 90s to low 100s Tuesday. One potential limiting factor
for highs over 100 is smoke from wildfires in southwest MT and
north central WY occasionally bringing hazy skies, although the
impacts at this time are expected to be minor.

Take precautions against the heat by staying indoors when
possible and drinking plenty of water. If you must be outdoors,
wear light colored clothes and take breaks in the shade. There
are also increased fire weather concerns at this time, so take
care not to cause a spark! Archer

Wednesday through Sunday...

Strong ridge will bring hot & dry weather on Wednesday, with temps
in the mid 90s to 100+ degrees and min RHs of 10-15% (if not a bit
lower). Latest model trends are showing a weak shortwave lifting
thru central MT late Tuesday night and a shift to light N-NE winds
over the west half of our cwa Wednesday. This could introduce a
bit of "cooling" for our west, while hottest temps exist within
thermal trof over our east. This is a hot air mass and would not
be surprised to see temps push 105F at places like Miles City and
Broadus, while Billings sits around 100F. Daily records will be
challenged at each of our climate stations. Also, the arrival of
high level monsoon moisture from the SW may be enough for a few
late day very high-based weak thunderstorms over/near the
mountains. Still some details to work out for Wednesday, but the
overall ensemble consensus brings a cold front across late
Wednesday night or early Thursday, which considering the air mass
is a better time for a fropa as it gives a chance for some RH
recovery first. Thursday will be cooler (80s) w/ higher humidity
(mins in 20s). Of course, fire concerns will be elevated Wednesday
and Wednesday evening and this is a time to be sure not to spark
a fire.

Look for temps close to normal Thursday through the weekend with
highs generally in the 80s. There is potential for additional
backdoor cooling Friday with another clipper emerging in the
developing NW flow aloft, so cannot rule out some 70s in the east.
Shortwave passage itself will bring a low chance (20-30%) of
showers and thunderstorms Thursday into Thursday night. Through
this period heights will remain above normal with a ridge axis to
our west, and the cooler temps will be a result of easterly winds
associated with Canadian high pressure over the northern plains.
Pwats will be higher and cannot rule out a few showers and
thunderstorms at some point Friday thru the weekend, but overall
the pattern is looking benign.

JKL


&&

.AVIATION...

Showers and thunderstorms east of Rosebud County will exit into
the Dakotas early this morning by around 10z. These storms are
capable of producing 30+ knot wind gusts along with locally heavy
rain and brief MVFR-IFR. After a break this morning, isolated
thunderstorms are expected in the afternoon and early evening, but
the activity will be weaker than Sunday. Otherwise, VFR will
prevail over the next 24 hours. Slant range visibility will
continue to be reduced at times from regional wildfires. JKL

&&

.PRELIMINARY POINT TEMP/POPS...

    Tdy Tue     Wed     Thu     Fri     Sat     Sun
-------------------------------------------------------
BIL 093 062/099 065/099 065/086 060/083 057/084 057/088
    1/U 10/U    00/U    11/U    11/U    00/U    01/U
LVM 089 054/096 058/095 054/086 050/083 049/084 051/088
    2/U 10/U    00/U    11/U    10/U    00/U    02/T
HDN 093 060/101 062/100 063/088 058/084 056/084 056/090
    0/U 10/G    00/U    11/U    21/U    10/U    00/U
MLS 092 065/101 071/101 068/087 059/081 056/079 056/084
    1/U 10/G    00/G    11/U    31/U    10/U    00/U
4BQ 090 064/097 072/101 068/088 060/080 057/078 056/083
    1/U 00/U    00/G    10/U    42/W    21/U    10/U
BHK 089 061/095 066/100 063/085 055/079 050/076 050/079
    1/U 10/U    00/U    11/U    21/U    20/U    00/U
SHR 090 058/096 061/098 061/086 055/081 052/081 052/085
    1/K 00/U    00/U    01/U    32/T    21/U    12/T

&&

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

&&

$$
weather.gov/billings