040
FXUS65 KBYZ 300710
AFDBYZ

Area Forecast Discussion
National Weather Service Billings MT
110 AM MDT Tue Jun 30 2026

.KEY MESSAGES...
- Breezy west winds continue today; isolated late day showers and
  weak thunderstorms west.

- Seasonable temperatures through the week.

- Increasing thunderstorm potential Wednesday through Friday;
  strong to severe storms possible.

- For the 4th of July (Saturday), temps in the upper 70s to lower
  80s, and a slight chance of thunderstorms east.

&&

.DISCUSSION...
Through next Monday...

Satellite imagery shows an upper low over far northeast MT lifting
to the northeast. Precipitation has for the most part ended, but
a few light showers may linger early this morning over the western
mountains and in our north. Downslope gradients remain and breezy
west winds will continue, with a trend toward lightening winds in
the west by afternoon as pressure falls are induced to our west,
courtesy of a shortwave over WA/OR. By the end of the day the
dynamic low to our northeast should be over southern Manitoba. As
temps warm to the 70s to near 80F today (still a bit cooler than
normal), there should be enough instability for isolated weak
thunderstorms over the west by late afternoon. There also is weak
energy lifting out of WY that may produce a few showers over our
S/SE tonight. All of this activity should stay benign.

Though it`s been a cool/wet couple of days, NW flow on the back
side of the departing low is spreading Canadian wildfire smoke
into northern MT. This should be short-lived, but northern
portions of our cwa could see hazy skies today.

A climate tidbit: If Billings airport fails to reach 80F today
(forecast high is 78F), it will have gone the last 2 weeks of June
with high temps of 79F or less. This has only happened one other
time, in 1951.

General troffing with below normal heights remains over the
northern Rockies through the remainder of the week. Embedded
shortwaves and an increase in moisture (plus seasonable temps)
look to bring a daily chance of thunderstorms Wednesday through
Friday. There isn`t a single period that stands out, but overall
there is a risk of strong to severe storms on these days, per
ensembles and AI convective outlooks, which are consistent with a
conceptual model. Greatest potential for severe wx seems to be
Thu/Fri and in the east. Something to watch. With pwats jumping up
to near an inch, heavy rain will be something to ponder as well.

Final shortwave moves east by Saturday. This looks to be a mostly
quiet weather day but cannot rule out a few thunderstorms over the
east, depending on the timing of this wave. As of now, weather is
looking favorable for 4th of July festivities, with temps in the
upper 70s to mid 80s and mostly light winds.

Sunday is also looking dry, and a strengthening ridge should push
temps further into the 80s to lower 90s. Model consensus is for
another warm day Monday. At some point early next week there may
be a shortwave that flattens the ridge and brings the next chance
of thunderstorms...but a lot of uncertainty here. Generally
speaking, the weather pattern is looking "mid-summery" into next
week.

JKL

.AVIATION...

A disturbance will drop into the area in the early morning hours
producing light shower activity over the western half of the
forecast area. Do not expect reduced flight categories from this
activity, with ceilings dropping to around 4kft AGL for KLVM/KBIL.
That said mountain obscuration for the western mountains will
continue through mid morning(16z). This activity will diminish
11-14z as it slides southward. During this time westerly winds
will re-develop, with gusts 20 to 30kts expected to be widespread
by 16-18z across the area. Isolated shower and thunderstorm
activity will develop over the western mountains around 19z and
spread east to around the Billings area through 02z this evening.
Impactful coverage with this activity should be confined to the
western foothills (KLVM/K6S0/K3HT) with local MVFR conditions and
gusts to 40kts possible (prob30)with stronger the stronger cells.
By 02-04z surface inversion development will reduce wind gusts and
diminish convective activity. Chambers

&&

.PRELIMINARY POINT TEMP/POPS...

    Tdy Wed     Thu     Fri     Sat     Sun     Mon
-------------------------------------------------------
BIL 078 053/082 055/084 057/084 056/084 059/091 063/092
    0/U 13/T    33/T    23/T    41/U    00/U    00/U
LVM 072 044/076 046/079 049/079 047/081 050/089 055/089
    3/T 36/T    53/T    25/T    61/U    00/U    01/U
HDN 080 051/085 055/087 056/086 054/085 056/092 061/094
    0/U 12/T    23/T    23/T    41/U    00/U    00/U
MLS 079 053/084 057/088 058/088 057/085 058/092 064/094
    0/N 00/U    22/T    24/T    42/W    10/U    10/U
4BQ 079 054/084 057/088 058/089 058/083 057/091 064/094
    0/U 21/U    12/T    24/T    33/T    10/U    11/U
BHK 077 051/082 055/087 055/087 055/082 054/088 060/091
    0/N 01/U    14/T    26/T    73/T    21/U    11/U
SHR 078 048/081 051/084 053/085 052/082 052/090 058/092
    1/U 12/T    23/T    23/T    43/T    00/U    01/U

&&

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

&&

$$
weather.gov/billings