164
FXUS65 KBYZ 091050
AFDBYZ

Area Forecast Discussion...Updated
National Weather Service Billings MT
450 AM MDT Sun Aug 9 2026

.KEY MESSAGES...

- Hot, dry and occasionally breezy with elevated fire weather
  conditions today.

- Wildfire smoke keeps skies hazy for the next several days, and
  will occasionally reduce air quality. For the latest air
  quality, visit airnow.gov.

- Increasing chance of thunderstorms in southeast Montana Tuesday
  through Wednesday.

- Cooler with a greater chance (25-60%) of showers and
  thunderstorms across the area to end the week.

&&

.UPDATE...

A weak shortwave is bringing enough instability for isolated
light showers and an occasional rumble of thunder over southeast
Montana and northern Wyoming early this morning. Archer

&&

.DISCUSSION...
Next 7 days (Through next Saturday)...

Low amplitude upper ridge centered over Utah continues to dominate
the western CONUS. Water-vapor imagery shows monsoon moisture
suppressed to our south, keeping us dry while significant wildfire
smoke advects into our region from the Pacific NW. Generally
speaking, the westerly flow aloft will continue to push
considerable smoke into our region from the numerous wildfires
over the Pacific NW.

There is a weak shortwave moving across Montana overnight which
may produce some increase in mid/high clouds from west to east
into this morning. Forecast soundings show some very elevated
moisture and instability (near 500mb) and this should yield areas
of high-based ACCAS and perhaps virga. Very dry boundary layer
remains so will not mention any risk of showers. Otherwise, Sunday
will be not be quite as warm, dry, nor windy as yesterday. While
we do not have any fire weather highlights posted for our CWA, Fire
weather conditions will remain elevated today. By tomorrow
evening, as southeasterly low level jet develops out of western
SD, we could see a few weak t-storms pop up in far southeast MT.
Monday & Tuesday will remain warm (upper 80s to mid 90s), but
model progs indicate PWATs will gradually increase, mainly due to
advection of moisture from the Great Plains. Any chance of
convection on these days will be low (10-20%) and confined to
areas near the Dakota borders while the western section of our CWA
remains much drier with RH readings in the low-mid teens.

By Wednesday, easterly low level flow will have PWAT levels
back up to around an inch as far west as Billings, and this is
backed up by majority of ensemble members. Upper to mid level flow
backs to the southwest as an upper trough drops into the Pacific
NW. This could allow some weak impulses to cross our area
providing a trigger for convection fed by the increasing moisture.
Thus, look for an increasing chance of thunderstorms by midweek
with high temps trending down into the 80s.

Expect a greater potential for showers and t-storms along with
cooler temps Thursday through Saturday as that aforementioned
trough tracks across the Canada/Montana border. Highs will be a
little below normal in the 70s to lower 80s. While forcing may be
limited directly over our area, we should still see at least a
chance of scattered showers/thunderstorms (20-60% coverage) with
the best chance on Thursday. Humidities will be seasonably high to
end the week (mins above 40%) but the increasing risk of
lightning could be problematic given the hot & dry weather
occurring now. Most of our cwa has not seen measurable precip yet
this month, and won`t over the next few days. BT


.AVIATION...

Wildfire smoke continues to impact the region, reducing slant
range visibility and occasionally reducing surface visibility to
MVFR. Winds will turn out of the northwest this afternoon, with
gusts around 15 to 20 kts through the evening. Archer

&&

.PRELIMINARY POINT TEMP/POPS...

    Tdy Mon     Tue     Wed     Thu     Fri     Sat
-------------------------------------------------------
BIL 093 062/093 064/092 064/085 060/078 057/074 054/077
    0/K 00/U    00/U    01/B    34/T    74/W    43/T
LVM 091 053/093 054/091 054/085 050/077 047/075 045/077
    0/K 00/U    00/U    01/U    34/T    64/T    44/T
HDN 094 057/094 059/093 060/087 056/080 053/075 050/078
    2/T 00/U    00/U    01/B    35/T    74/W    43/W
MLS 094 059/092 062/092 061/085 057/079 055/075 052/077
    0/K 00/U    00/U    13/T    56/T    85/T    32/W
4BQ 094 062/094 063/092 063/084 059/077 057/074 054/076
    2/T 00/U    00/U    15/T    67/T    76/T    53/T
BHK 090 056/089 057/090 055/082 052/075 050/073 048/075
    1/K 11/B    11/U    25/T    65/T    76/T    52/W
SHR 093 057/095 058/092 058/086 055/077 051/073 048/075
    2/T 00/U    00/U    02/T    57/T    77/T    56/T

&&

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

&&

$$
weather.gov/billings