Damaging Wind in Montana, August 13, 2025

Area Forecast Discussion
National Weather Service Billings MT
146 AM MDT Wed Aug 13 2025

.KEY MESSAGES...

- Hot Today with a few triple digit readings possible, along with
  dry and breezy conditions. Isolated afternoon/evening
  thunderstorms expected, producing locally strong wind gusts.

- Typical summer weather (temps in upper 80s to mid 90s) for late
  this week through the middle of next week. A low risk of
  thunderstorms each day.

&&

.DISCUSSION...
Through Thursday night...

Eastward moving 50kt jet streak responsible for this past evenings
convection will continue over the area tomorrow producing
another round of isolated high based convection. Storms will
initiate over the western mountains a bit earlier than Tuesday,
and spread eastward mainly along and south of I-90. The main
difference between Tuesdays convection and whats expected this
afternoon is less available moisture as PWATs drop below 0.75
toward 0.5 inches. Less moisture plus warmer mid level
temperatures will work harder against storm persistence once off
of the mountains. Any storms that do form will have a better
chance of producing locally strong wind gusts over 50 mph as well
due to the drier airmass. Latest HREF shows a few strong to
possibly severe wind gusts arriving in Billings around 5pm, so
those with outdoor/fair plans should be alert if storms do
develop. A second area of convection will develop along a
convergence/moisture boundary along the eastern state line mid
afternoon. This will impact mainly Fallon and Carter counties for
a brief period of time before storms shift east into the Dakotas.
The eastern storms will have more moisture/CAPE/Shear to work with
thus have the better potential to become strong before exiting
the area.

With the drier air, plenty of sun, and downslope westerly flow,
expect temperatures in the mid to upper 90s to be widespread this
afternoon. Probabilities for reaching the triple digits are in the
20 to 40 percent range from Billings east along the Yellowstone
river valley into Forsyth and Miles City.

A disturbance crossing east to west across southern Canada
will push a weak cold front/northerly wind shift through the area
early Thursday morning. This frontal passage looks mainly dry but
will push temperatures down 7 to 10 degrees compared to
Wednesday. Very isolated convection remains possible over the
southern tier of counties where the frontal boundary backs into
the mountains. But latest model guidance isn't making too much of
this.

Fire Weather...With hot conditions, drier air, and wind gusts 20
to 30 mph (mainly west of Billings) today, fire weather conditions
will be elevated. Fuels conditions are not to the level of a Red
Flag being necessary, but everyone still needs to be very careful
with any activities that could cause a fire. In addition, Tuesday
evening thunderstorms produced thousands of cloud to ground
lightning strikes across the area. The hot, dry, breezy
conditions will likely expose some lightning starts this
afternoon. Chambers

Friday through Tuesday...

The forecast for Friday into early next week continues to look
very typical for mid August with warm temperatures and generally
dry conditions as upper level ridging builds over the region. With
that said, a few shortwave impulses in the southwesterly flow
aloft, combined with potentially some monsoonal moisture, will
bring at least a slight chance of precipitation mainly to the
mountains and foothills most days this weekend into early next
week. While uncertain at this time, some showers and/or
thunderstorms could also move out over the plains, but chances
remain spotty. With any activity that does form during this time,
the high-based nature will favor gusty winds, but precipitable
water values look to be high enough to support localized rainfall
as well.

As we move to the 2nd half of August it is prudent to keep an eye
on the western Pacific tropics, as typhoons can disrupt the
downstream longwave pattern. Models are hinting at 2 or 3 tropical
systems over the next 1-2 weeks. Stay tuned. JKL/Arends

&&

.AVIATION...

The scattered showers and thunderstorms over eastern Montana
early this morning will continue to move east into the Dakotas by
10 to 11Z. Underneath this activity, brief MVFR conditions are
possible with heavy rain. Otherwise, VFR conditions will prevail.
By this afternoon, breezy westerly winds will develop over the
foothills west of Billings with gusts of 20 to 30 knots forecast.
Isolated showers and thunderstorms are also possible this
afternoon and evening in southern Montana and northern Wyoming,
but confidence remains lower on TS impacts to TAF sites. Arends

&&

.PRELIMINARY POINT TEMP/POPS...

    Tdy Thu     Fri     Sat     Sun     Mon     Tue
-------------------------------------------------------
BIL 097 063/091 060/089 061/093 063/092 061/093 062/094
    2/T 20/U    10/U    01/U    11/U    11/U    10/U
LVM 094 054/091 050/089 052/090 054/089 053/091 054/092
    2/T 21/U    11/U    11/U    12/T    21/U    10/U
HDN 097 061/091 059/091 058/093 061/093 059/095 061/095
    1/U 20/U    10/U    10/U    11/U    11/U    10/U
MLS 095 064/089 061/089 064/092 064/089 064/093 065/094
    0/U 00/U    10/U    11/U    12/T    21/U    10/U
4BQ 094 065/090 062/090 065/089 064/088 064/092 064/093
    1/U 10/U    11/U    11/B    22/T    21/U    11/U
BHK 093 061/088 057/085 060/082 059/083 060/088 061/089
    2/T 00/U    21/U    22/T    22/T    21/U    10/U
SHR 092 059/090 056/089 058/089 059/089 058/092 059/093
    2/T 20/U    11/U    21/B    12/T    11/U    11/U

&&

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

&&

weather.gov/billings