515
FXUS65 KBYZ 150812
AFDBYZ

Area Forecast Discussion
National Weather Service Billings MT
212 AM MDT Sun Jun 15 2025

.KEY MESSAGES...

- Enhanced risk (3/5) of severe thunderstorms today. Main threats
  are strong winds, large hail, and heavy rain. A small chance
  for tornadoes.

- There is daily potential for thunderstorms into Tuesday; some
  severe thunderstorms are possible. Monitor the forecast.

- Quieter weather pattern for the second half of the week.

&&

.DISCUSSION...

Today through Monday...

Expect patchy fog, especially near the Dakota border, through
this morning and again tonight into Monday morning.

Afternoon/evening thunderstorms are expected today and Monday,
with today having the better chance for severe storms to develop.

Today, CAPE values are expected to be around 2000-3000 J/kg, and
moisture remains sufficient for storm development, with dewpoints
in the 50s and 60s F. Hodographs show wind profiles that favor
large hail, with a 10% chance of hail greater than 2 inches. In
addition, for locations east of Billings, there is a 10% chance
for wind gusts greater than 74 mph. Additional potential impacts
include heavy rain and a small chance (2%) for tornadoes. The
best timeframe for storm development is 3 PM through midnight. The
Storm Prediction Center has issued an Enhanced Risk (level 3 of
5) for today.

For Monday, conditions will be less favorable, but still
sufficient for isolated severe storms to develop. CAPE values
will be lower, around 1000-2000 J/kg and moisture will decrease,
with dewpoints generally in the 50s F. The SPC has issued a
Marginal Risk (level 1 of 5) for Monday. Archer

Tuesday through Saturday...

Active weather continues into the new week. Showers and
thunderstorms will be possible Tuesday and Wednesday, with some
strong thunderstorms possible on Tuesday. Deterministic models
show 1000 to 1500 J/kg of MUCAPE and modest bulk shear up to 40
knots. Precipitable water values will continue to be around or
above 1 inch for much of the forecast area through Wednesday
allowing for heavy rainfall with any storms. High temperatures on
Tuesday will be in the 70s.

A ridge is depicted building into the Northern Rockies Wednesday
into next weekend bringing drier conditions and temperatures in
the 70s and 80s. Ensembles depict a deepening upper low over the
PNW next weekend, bringing cooler and wetter conditions to the
region. It is too soon to determine potential impacts from this
but it will be worth monitoring through the week.

Matos
&&

.AVIATION...

VFR conditions will prevail into Sunday afternoon before a round
of thunderstorms is forecast across south central Montana. Periods
of MVFR conditions will be possible under heavy storms. The
strongest thunderstorms will be capable of producing strong wind
gusts in excess of 65 knots along with hail greater than 2 inches
in diameter. Timing for thunderstorms is between 3pm to midnight,
with the strongest storms favored around and east of KBIL. Matos

&&

.PRELIMINARY POINT TEMP/POPS...

    Tdy Mon     Tue     Wed     Thu     Fri     Sat
-------------------------------------------------------
BIL 083 056/079 055/074 054/084 057/088 058/086 056/076
    4/T 75/T    56/T    10/U    00/U    12/T    21/U
LVM 082 050/077 049/074 047/082 050/087 051/082 047/073
    6/T 66/T    55/T    10/U    01/U    22/T    23/T
HDN 086 056/079 055/073 051/084 056/089 058/088 055/079
    5/T 84/T    67/T    20/U    00/U    11/U    21/U
MLS 087 060/080 057/075 054/083 057/089 060/087 059/081
    4/T 93/T    45/T    31/U    10/U    31/U    31/U
4BQ 088 058/078 057/071 054/081 058/088 060/088 060/083
    3/T 82/T    67/T    20/U    00/U    11/U    21/U
BHK 083 056/078 053/075 051/080 054/086 057/084 056/079
    2/T 82/T    35/T    31/U    10/U    21/U    31/U
SHR 085 052/076 051/071 048/080 052/088 057/088 055/081
    5/T 55/T    78/T    20/U    00/U    11/U    11/U

&&

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

&&

$$
weather.gov/billings