776
FXUS65 KBYZ 260755
AFDBYZ

Area Forecast Discussion
National Weather Service Billings MT
155 AM MDT Sat Jul 26 2025

.KEY MESSAGES...

- Scattered thunderstorms this afternoon and evening have the
  potential to produce strong/erratic wind gusts.

- Daily chance of showers and thunderstorms Sunday through much of
  next week. Storms will become wetter. The best potential for
  more widespread precipitation is next Tuesday through Thursday.

- Near normal temperatures (upper 80s to mid 90s) through the
  weekend turning slightly cooler than normal next week.

&&

.DISCUSSION...

Through Monday Night...

Satellite imagery shows SW flow over the region in between
shortwaves. One is exiting to our northeast while upstream a more
pronounced wave is lifting thru UT. The energy to our south will
provide ascent for the next round of showers and t-storms this
afternoon and evening. In meantime, most of our forecast area is
dry and mostly clear, but there is what looks to be an area of
altocumulus over our southeast, and in fact a couple light
showers near Birney and Volborg. Not much forcing here but some
elevated instability remains, so isolated sprinkles possible over
far southeast MT for the next few hours.

Surface winds will turn easterly today and this will allow for
pwats to increase slightly from yesterday (looking at 0.75" most
places to near an inch in the far east). CAMs show today`s
convection developing in two locations: the western mountains and
foothills beginning around 19-20Z (a region of cooler mid level
temps), and our southeast by 22z (per track of wave lifting from
the south). Today`s bulk shear is marginal for severe storms but
inverted-v soundings are somewhat suggestive of microbursts, so
the main risk from today`s convection is wind. HREF indeed shows
two favored regions for strong convective winds: our W/NW and the
SE. The neural network shows highest severe probs in our far east
and this seems reasonable given the stronger shortwave clipping
that area late today. The day1 outlook highlights most of our
forecast area for a marginal risk of severe t-storms. Storms in
our far east could also produce brief heavy rain.

Convection will exit through the evening and this will be followed
by another dry period late tonight thru Sunday morning. With less
forcing, Sunday`s afternoon and evening t-storms are expected to
be more benign and have greatest coverage in our west and north.
One thing to note is that pwats Sunday should be pretty similar
to today.

A more significant jump in atmospheric moisture occurs Monday as
low level easterly flow deepens, pushing pwats to near an inch
even in our west. T-storms Monday afternoon and evening will be
wetter and have the potential to be severe, so this is something
to monitor. The day3 outlook highlights much of our cwa for a
marginal risk of severe t-storms.

Temperatures today and Sunday will be slightly cooler than
yesterday and very close to normal. Look for highs in the upper
80s to mid 90s. Monday sees a cooling trend begin with highs in
the 80s.

JKL

Tuesday through Friday...

An active weather pattern will continue into August. An upper low
moving across Canada will bring easterly to northeasterly surface
flow to the region. Because of this, low level moisture will be
abundant, with PWAT values increasing to more than an inch,
Tuesday through Thursday. Latest soundings from models depict
minimal shear, which will allow for heavy rainfall in storms.
Strong to severe thunderstorms will also be possible throughout
the new week. The latest Extreme Forecast Index (EFI) is showing
values around 0.95 (1 being the most extreme or anamolous) with a
shift of tails of 1 to 2 (very anamolous) for CAPE on Wednesday
and Thursday. Models show MLCAPE values in excess of 1200 J/kg
across the area on Wednesday and Thursday. This includes our
western zones, where the shift of tails is highlighting the
anomaly. Continue to monitor the forecast as an active
thunderstorm pattern remains in place.

As for temperatures, highs will be around normal, in the 80s and
90s for the middle half of next week. Temperatures are shown
dipping into the upper 70s and 80s by late next week with a ridge
breakdown.

Matos

&&

.AVIATION...

Expect another round of showers/thunderstorms this afternoon and
evening. These storms have the potential to produce strong and
erratic winds (localized gusts of 40+ knots), and perhaps brief
MVFR conditions. The Montana TAF sites have the greatest risk of
TS impacts today (30% chance). Otherwise, VFR will prevail across
the region, though slant range visibility may be reduced at times
due to lofted wildfire smoke. JKL

&&

.PRELIMINARY POINT TEMP/POPS...

    Tdy Sun     Mon     Tue     Wed     Thu     Fri
-------------------------------------------------------
BIL 091 062/090 060/087 061/081 062/082 061/084 062/087
    2/T 22/T    12/T    23/T    54/T    43/T    33/T
LVM 088 052/088 051/087 052/081 054/081 054/084 054/086
    3/T 23/T    23/T    23/T    45/T    44/T    34/T
HDN 093 059/092 059/090 060/082 060/085 061/087 060/088
    2/T 22/T    11/U    23/T    54/T    52/T    32/T
MLS 095 064/092 064/087 062/082 062/081 062/083 062/087
    1/H 31/U    22/T    33/T    54/T    42/T    32/T
4BQ 093 061/092 063/091 063/083 062/079 063/081 062/083
    2/T 30/U    11/U    33/T    64/T    52/T    22/T
BHK 093 060/089 060/084 057/078 057/077 057/078 057/079
    1/H 41/U    23/T    53/T    53/T    42/W    22/T
SHR 092 055/092 056/089 057/081 057/083 056/084 057/085
    3/T 20/U    11/U    23/T    55/T    54/T    33/T

&&

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

&&

$$
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