160
FXUS65 KBYZ 151928
AFDBYZ

Area Forecast Discussion
National Weather Service Billings MT
128 PM MDT Sat Aug 15 2026

.KEY MESSAGES...

- Scattered showers and thunderstorms on tap for this evening,
  mainly over south central MT. Late day scattered showers and
  isolated thunderstorms continue through Monday.

- A cold front Tuesday lowers temperatures a bit to upper
  70s/lower 80s, and brings an increased chance of
  showers/thunderstorms.

- Warmer and mainly dry conditions look to return for latter part
  of next week.


&&

.DISCUSSION...

Tonight through Friday...

Weak west/southwest flow will bring some disturbances into our
region today. As highs peak in the upper 70s late today, we
should see convective initiation come off the higher terrain into
the foothills and nearby lower elevations as they track slowly
east in the evening. A few storms may be capable of brief heavy
rain with the projected MUCAPE 500-1000 J/kg and PWATs around 0.85
inches. Convection should weaken after dark and drift east
overnight as isolated light showers or sprinkles. Dewpoint
depressions suggest patchy fog is again possible later tonight
into early Sunday morning, particularly in the eastern river
valleys and out west in the Paradise Valley/Livingston vicinity.

CAMs indicate the possibility of a few strong storms in
our far east (Fallon, Carter Counties) Sunday as some energy
exits the state where MUCAPE values push 1000 J/kg and PWATs of
over 1.0 inches exist. In the meantime, some weaker isolated to
scattered activity is expected over the mountains and western
portions of the CWA in the afternoon. Highs Sunday will warm into
the lower to mid 80s.

For the work week ahead, look for seasonal temps mainly in the
80s as high pressure aloft prevails. A weak cold front Tuesday
will drop temps a bit to upper 70s and lower 80s, and produce the
best chance of precipitation for the week (25-50% coverage), but
otherwise look for just a slight chance of showers each day,
mainly over the high country. Temps will trend gradually up
pushing 90 by Friday. BT


.AVIATION...

Shower and thunderstorm chances (20-60%) will continue through
15Z Sunday. Heavy rain may cause MVFR conditions. The best
precipitation chances are for the mountains and foothills. Fog
will be possible at all TAF sites Sunday morning from 09Z through
15Z. Fog has been left out of the TAFS due to low confidence. The
best potential for fog development will be locations east of
Billings. Potential TS times are listed below:

KLVM 21-06z
KBIL 00-05z
KSHR 21-04z

&&

.PRELIMINARY POINT TEMP/POPS...

    Sun     Mon     Tue     Wed     Thu     Fri     Sat
-----------------------------------------------------------
BIL 057/084 058/084 060/080 056/084 058/087 060/090 062/091
    31/U    31/B    55/T    31/B    20/U    11/U    21/B
LVM 044/083 047/084 048/080 045/083 047/086 050/089 053/089
    62/T    31/B    75/T    51/B    21/U    11/U    23/T
HDN 052/085 053/085 056/082 051/086 052/089 054/092 058/094
    21/U    21/B    54/T    30/B    20/U    10/U    11/B
MLS 054/084 057/084 058/080 054/084 056/087 058/090 061/092
    12/W    21/B    64/T    21/B    10/U    00/U    11/B
4BQ 055/084 058/085 060/081 056/084 058/087 059/090 062/093
    12/T    21/B    64/T    41/B    21/U    10/U    11/U
BHK 049/083 053/083 054/079 049/082 053/086 054/088 056/091
    02/T    31/B    65/T    21/B    21/U    10/U    11/U
SHR 048/080 050/082 053/078 049/081 050/085 052/089 056/091
    22/T    21/B    56/T    51/B    11/U    01/U    12/T

&&

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

&&

$$
weather.gov/billings