Sheridan, Wyoming 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

958
FXUS65 KBYZ 191955
AFDBYZ

Area Forecast Discussion
National Weather Service Billings MT
155 PM MDT Sat Jul 19 2025

.KEY MESSAGES...

- Late this afternoon and evening, scattered strong to severe
  thunderstorms are possible east of Rosebud County. Main threats
  are large hail, strong winds, and heavy rain.

- Isolated to scattered thunderstorms expected Sunday, with strong
  to severe storms possible again east of Rosebud County.

- Early next week looks cooler (70s and 80s) with daily chances of
  showers and thunderstorms.

&&

.DISCUSSION...
Through Sunday Night...

There remains a slight risk of severe storms east of Rosebud
County between 3-9pm today. Risks include large hail, strong
winds, heavy rain and even a small chance of a tornado. Current
obs/mesoanalysis show easterly surface winds and high dew points
(into the lower 60s) as far west as Rosebud County as of 1pm.
Instability is capped but growing, with MLCapes to 1500 j/kg along
an axis from northeast Rosebud to southern Carter. Bulk shear is
more than enough for severe storms. There is a 500mb speed max
moving from central ID to south central MT, so ascent is
increasing. All ingredients are there for severe t-storms in our
east...the question is how far west is the threat? For reasons
already mentioned it appears the risk is from Forsyth to Broadus
eastward, a bit further west than the day1 outlook, but will need
to monitor the location of the surface trof over the next couple
hours. Latest HRRR has strong t-storms developing just west of
Forsyth by 21Z and this timing seems reasonable. To the west of
the surface trof, low levels are much drier w/ mixed west winds. A
few weak t-storms are possible over the next few hours in this
area, which includes Billings.

The severe window is fairly short-lived as convection should shift
into the Dakotas by around sunset. The remainder of the night will
be mostly dry, though some showers may continue to develop in our
northeast after 06z, courtesy of the upstream shortwave lifting
thru northeast MT.

The chance of afternoon and evening t-storms continues Sunday as
we remain under broad troffing and slowly lowering heights, with
another weak shortwave skirting thru central MT. Best chance of
storms should be over our west/north/east. In the east, low level
easterly winds continue to support elevated moisture/instability,
and there seems to be an increasing risk of more severe t-storms
east of Rosebud County (recent Neural Network runs show rising
probabilities in this area), though the air mass could be affected
by today`s convection. Either way, active weather continues with
greatest potential impacts in our east.

Given the east winds and high dew points, there is a reasonable
expectation of patchy late night fog/stratus close to thew Dakotas
border tonight and again Sunday night.

Regarding temps, most locations will see upper 80s to mid 90s
today, but highs should drop to the mid 80s to lower 90s on
Sunday as we enter a gradual cooling trend.

JKL

Monday through Friday...

Southwest flow in place now will remain in place for most of the
week. Low to moderate chances of showers and thunderstorms are in
the forecast Monday through Wednesday. Instability will be
sufficient for strong to severe thunderstorms with PWATS in the 1
inch to nearly 1.5 inch range. For Monday a low level jet will
likely provide forcing with an approaching 500 jet passing through
Wednesday bringing the forcing necessary. With increased
atmospheric moisture, heavy rain will be an added threat during
this timeframe. Late week, ensembles bring back a westerly flow,
allowing for drier and warmer conditions. There is a slight hint
at a transition into a southwesterly flow which would continue
afternoon shower and thunderstorm chances.

High temperatures will be in the upper 70s and 80s Monday through
Wednesday, warming into the 80s to mid 90s by Friday.

&&

.AVIATION...

Late this afternoon and evening, expect isolated showers &
t-storms west of Rosebud County, and scattered t-storms to the
east. Eastern storms have the potential to produce large hail,
strong winds, heavy rain and brief reductions to IFR (most likely
to impact KMLS-KBHK-K97M). Prime time for t-storms at KMLS is
22-02Z. Late tonight, cannot rule out patchy fog and low clouds
near the Dakotas border once again...though this is uncertain at
this time (30% chance). There is a chance of t-storms again Sunday
afternoon/evening, with strong to severe storms possible in the
east.

Outside of convection and localized eastern fog/stratus, VFR will
prevail regionwide over the next 24 hours. Slant range visibility
will be reduced at times due to wildfire smoke from the west.

JKL

&&

.PRELIMINARY POINT TEMP/POPS...

    Sun     Mon     Tue     Wed     Thu     Fri     Sat
-----------------------------------------------------------
BIL 061/090 060/087 060/082 059/080 058/090 062/094 061/093
    22/T    21/B    43/T    52/T    21/U    11/U    11/U
LVM 051/087 052/086 052/082 049/083 050/089 053/090 052/092
    12/T    13/T    44/T    33/T    11/U    11/U    11/B
HDN 059/090 059/090 060/083 057/082 056/090 059/094 058/094
    22/T    21/B    42/T    52/T    21/U    11/U    10/U
MLS 062/088 063/089 063/083 059/080 058/091 063/095 063/094
    33/T    41/B    51/B    52/T    21/U    11/U    11/U
4BQ 062/089 062/091 064/084 061/080 059/088 064/092 063/093
    22/T    21/B    41/B    52/T    41/U    21/U    10/U
BHK 057/084 058/083 060/082 056/078 054/085 059/090 059/090
    53/T    41/B    51/B    52/T    31/U    11/U    11/B
SHR 054/091 054/090 055/083 054/081 053/089 056/092 056/092
    22/T    11/B    22/T    43/T    21/U    11/U    11/U

&&

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

&&

$$
weather.gov/billings