080
FXUS65 KBYZ 030223
AFDBYZ

Area Forecast Discussion
National Weather Service Billings MT
823 PM MDT Wed Jul 2 2025

.KEY MESSAGES...

- Warm Thursday with high temperatures in the high 80s to mid 90s.

- Scattered showers and thunderstorms Thursday. There is a risk
  level 1 of 5 for severe storms near the Dakotas border.

- Near-normal temperatures return Friday with a daily chance of
  showers and thunderstorms through the holiday weekend.

&&

.UPDATE...
Miles City and Brandenberg each topped out at 101F today, the
first 100-degree day of the season. Temps are cooling as we
approach sunset and have cancelled the Heat Advisory.

Convection across the west half of our cwa in the afternoon and
early evening did not become strong but did produce some erratic
wind gusts to near 40 mph along with only spotty light rain. As
of 02z activity is isolated, but just recently some weak t-storms
developed near Busby and Colstrip, and some stronger cells are
lifting thru northeast WY toward southeast MT. Despite the warm
mid levels (700mb temps analyzed to be near +15C), will need to
keep an eye on convection over our east over the next few hours as
it may be aided by a developing southeasterly low level jet.
Mesoanalysis shows 850mb dewpts exceeding 12C from the north side
of the Black Hills advecting into far southeast MT. The HRRR
indeed shows come convection spreading thru southeast MT between
now and 08Z tonight. Pwats are analyzed to be over an inch, so
some heavy rain is possible, along with gusty winds and small
hail. To the west, there is weak activity along the foothills but
it seems to be fading, and expect the west half of our cwa to be
pretty much dry by sunset...as there is a lack of forcing with the
upper level ridge in place. Look for more showers & t-storms
tomorrow.

Forecast is in good shape, but have adjusted pops/wx per current
trends, expanding t-storm coverage a bit over our east over the
next several hours.

JKL

&&

.DISCUSSION...
Through Thursday night...

Showers and thunderstorms will decrease overnight tonight coming
to an end around 06Z. The main threat with these storms will be
strong winds and heavy rain. Low temperatures tonight will range
from the mid 50s F in the west to mid 60s F in the east.

500 mb troughing over the southwestern US will create monsoonal
conditions over the short term. Thermal low pressure over the
western US will create southerly winds over the plains bringing
widespread PWAT values over 1 inch. Soundings indicate that 0-3 km
lapse rates will be near 10 C/km. This efficient surface heating
and an upper level wave moving through southeast Montana will
combine to create forcing for showers and thunderstorms.

The monsoonal nature of these thunderstorms with inverted v
soundings, high LCLs, and DCAPE values around 1,500 J/kg will lead
to pulse convection with a few embedded strong thunderstorms
Thursday evening. The greatest risk for strong thunderstorms will
be locations along the Dakotas border where the Storm Prediction
Center has issued a risk level 1 of 5 for severe thunderstorms.
The main threats with these storms are expected to be strong winds
in excess of 60 mph and heavy rainfall.

Tempeatures decrease for most of southeast Montana Thursday as a
weak cold front moves through. Locations west of Billings will see
temperatures in the high 80s F with low to mid 90s F to the east.
Probabilities for a high temperature over 100 F will be limited to
locations near Miles City along the Yellowstone River where
chances top out around 50%. Torgerson

Friday through Tuesday...

Active weather will continue through the weekend. A shortwave
trough is depicted by models moving through the region Friday into
Saturday. Along with this shortwave, moisture will increase
throughout all levels of the atmosphere, bringing PWATs of
0.8-1.5" (highest values in central-eastern areas). With this
much moisture available, the chance for heavy rainfall will
increase across the area. Based on current model guidance, strong
storms do not look to be widespread, with only 250-700 J/kg) of
MUCAPE. Most of this CAPE looks to be confined to the mountains.
The chance for showers and thunderstorms is moderate to high
(greater than 50%) on Friday with the best chance in the mountains
and foothills.

The chance for precipitation will linger through Saturday with a
low to moderate chance (25-70%) of showers and thunderstorms.
There is uncertainty on the potential for strong storms on
Saturday, with the latest ECMWF depicting MUCAPE values of
1000-2000 J/kg but the GFS showing 300-800 J/kg. This will be
worth monitoring for anyone with outdoor plans.

Late Saturday into next week, ensembles depict the more zonal,
westerly flow aloft. This may cut off moisture availability and
lead to drier conditions. Temperatures will cool a bit Friday and
Saturday, with highs back around normals in the 70s and low 80s.
Despite more zonal flow building into the new week, ensembles
currently agree that highs will climb back into the mid 80s and
90s.

Matos

&&

.AVIATION...

Thunderstorm activity is trending down over southern MT, with
about a 30% chance of KMLS seeing a thunderstorm through around
04Z this evening. Showers and isolated thunderstorms will begin
developing around 15Z Thursday morning and track northeast
through the afternoon. The main threat with these storms will be
gusts of 35-45 kts. Brief heavy rainfall could also create MVFR
conditions under any thunderstorm. TS

&&

.PRELIMINARY POINT TEMP/POPS...

    Thu     Fri     Sat     Sun     Mon     Tue     Wed
-----------------------------------------------------------
BIL 065/092 064/086 059/080 054/080 057/088 060/090 061/093
    23/T    44/T    55/T    21/U    11/U    10/U    11/U
LVM 056/089 053/081 050/076 046/080 050/087 052/089 054/091
    25/T    48/T    76/T    21/U    11/U    10/U    11/U
HDN 062/093 062/088 058/082 052/081 055/090 058/091 058/093
    22/T    53/T    55/T    21/U    21/U    10/U    11/U
MLS 067/096 067/088 062/082 056/080 058/089 061/089 061/093
    21/B    32/T    55/T    41/B    21/U    21/U    10/U
4BQ 065/095 066/084 061/083 056/080 058/087 061/089 061/090
    22/T    52/T    43/T    31/U    21/U    20/U    11/U
BHK 065/096 064/086 058/081 052/077 054/083 056/085 057/087
    21/B    43/T    45/T    51/B    22/T    21/U    11/U
SHR 059/092 059/084 053/082 049/078 051/088 055/087 055/090
    23/T    55/T    44/T    21/U    11/U    11/U    11/U

&&

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

&&

$$
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