403
FXUS65 KBYZ 041413
AFDBYZ

Area Forecast Discussion
National Weather Service Billings MT
813 AM MDT Wed Jun 4 2025

.KEY MESSAGES...

- Scattered showers and isolated weak thunderstorms today and
  Thursday.

- Warming trend through the remainder of the week, with above
  normal temps returning Friday into the weekend.

- Rivers and streams are running high and fast, but cooler
  temperatures will slow mountain snowmelt and result in
  decreasing flows through the middle of the week.

- Next chance for widespread significant rainfall will be Tuesday
  next week.

&&

.UPDATE...
There remains a few light showers over the east half of our
forecast area as of 14z. As this activity continues to drift
eastward, a period of dry wx will be followed by scattered showers
and isolated t-storms this afternoon and evening. Satellite
imagery shows a distinct shortwave over southeast BC that will
provide ascent by late afternoon. Have made a few pops/wx/wind
tweaks based on current trends, otherwise forecast is in good
shape. No chance of severe wx today. JKL

&&

.DISCUSSION...

Through Thursday night...

Area remains under the upper trof for the next few days. Several
weak disturbances tracking southeast under this trof will keep a
chance for showers and isolated thunderstorms in the forecast for
the next few days, especially in the afternoon and evening hours.
That said, precipitation amounts with this activity will be
generally light. Temperatures will stay in the 60s today with
light northerly winds, turning southerly Thursday which will help
to warm temperatures into the 70s.

Snow showers are ongoing over the Beartooth mountains, so will
keep the Winter Weather advisory in place until expiration time at
6am. Do not anticipate needing to extend the advisory at this
time.

Hydrology...River gages show downward trends across most of the
area this morning, with gages over SE Montana still rising a bit
waiting on the diminishing flows to arrive later today. Despite
the lower water levels rivers and streams are still running high,
fast, and cold so continue to use extra caution recreating near
waterways, and consider staying off rivers and streams for a week
or so longer, past peak runoff. Chambers

Friday through Wednesday...

The weather in the long-term forecast remains relatively benign
with the lack of any robust system. On Friday, shortwave ridging
in the progressive northwest flow aloft looks to bring drier and
warmer conditions back to the region ahead of a mostly dry cold
front passage on Saturday. Behind this cold front on Saturday,
breezy conditions look to persist with northwesterly gusts
generally around 15 to 30 mph. On Sunday, cyclonic northwest flow
over the region may lead to a stray shower or two, but the chance
of precipitation remains low with drier air over the region (5 to
20 percent chance). By early next week, weak upper ridging looks
to build into the region, but additional energy rounding the ridge
will keep at least a low chance of precipitation in the forecast
for Monday and Tuesday (15 to 50 percent chance). By the middle of
next week, ensemble forecasts suggest more active weather could
return to the region.

Temperatures Friday through early next week are expected to warm
back into the 70s and 80s across the lower elevations. With the
weak upper level ridging Monday and Tuesday, the National Blend of
Models (NBM) continues to give a low to moderate chance of seeing
90 degrees these days mainly along the river valleys of eastern
Montana (25 to 50 percent chance). Otherwise, these warmer
temperatures will allow snowmelt to resume over the mountains, so
expect diurnal rises on streams and rivers to pick back up during
this time. Arends

&&

.AVIATION...

Isolated showers will taper off through the morning hours today.
By this afternoon and evening, another round of scattered showers
and isolated thunderstorms is expected over the region. The chance
of a TS impacting a TAF site is low (<20%). While VFR conditions
will prevail, any moderate shower or thunderstorm could produce
brief MVFR conditions. This shower activity will also obscure the
mountains at times. JKL

&&

.PRELIMINARY POINT TEMP/POPS...

    Tdy Thu     Fri     Sat     Sun     Mon     Tue
-------------------------------------------------------
BIL 067 048/071 047/080 055/084 057/081 055/085 056/086
    2/T 22/T    11/U    00/U    10/U    01/U    13/T
LVM 063 039/068 041/077 049/081 051/081 051/084 053/084
    2/T 22/T    11/B    10/U    11/U    11/U    24/T
HDN 068 047/072 045/081 054/084 056/081 052/085 053/087
    2/T 22/T    11/U    10/U    10/B    01/U    23/T
MLS 070 048/072 047/081 056/084 057/080 051/084 055/087
    2/T 22/T    21/U    01/B    10/U    00/U    12/W
4BQ 066 047/068 047/077 055/081 056/076 051/080 053/086
    4/T 23/T    21/U    00/U    10/B    00/U    12/W
BHK 068 043/068 044/077 052/081 050/075 046/079 050/083
    3/T 22/T    21/U    01/B    10/N    00/U    11/U
SHR 063 043/066 042/074 049/079 050/076 048/080 049/083
    4/T 26/T    22/T    11/U    11/U    01/U    24/T

&&

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

&&

$$
weather.gov/billings