513
FXUS65 KCYS 060531
AFDCYS

Area Forecast Discussion
National Weather Service Cheyenne WY
1130 PM MDT Sun Oct 5 2025

.KEY MESSAGES...

- Stratiform precipitation expected across portions of southeast
  Wyoming and western Nebraska tonight. High terrain locations
  will see snow while lower elevations can expect rain.

- Freeze Watch issued for portions of Carbon and Converse
  Counties Tuesday morning. Take precautions to protect
  sensitive vegetation.

&&

.SHORT TERM /THROUGH MONDAY NIGHT/...
Issued at 319 PM MDT Sun Oct 5 2025

Clouds continue to increase this afternoon as a shortwave approaches
from the west. Radar currently shows a few light showers across
portions of southeast Wyoming ahead of the shortwave. As the
shortwave moves into the CWA this evening, surface winds will turn
more easterly. Easterly winds will promote upslope flow along the
Laramie Range, leading to stratiform precipitation developing over
the Laramie Range and Interstate 25 corridor. Temperatures this
evening and overnight will be cold enough in the Laramie Range for
snow. The South Laramie Range will likely see a dusting while the
North Laramie Range could pick up a few inches of snow above 8000
feet. The Interstate 25 corridor is expected to stay rain. As the
overnight progresses and the shortwave continues to trek eastward,
stratiform precipitation will move into the Nebraska panhandle and
northern zones of the CWA. Once again, temperatures will likely be
warm enough for precipitation to stay as rain. Locations west of the
Laramie Range will likely face cooler temperatures, with
isolated locations coming close to freezing. Opted to keep
freeze products out of the forecast tonight/Monday morning as
ample cloud cover out west may keep temperatures from actually
touching freezing.

A few lingering showers will still be possible throughout the day
Monday as the shortwave is sluggish to make its way out of the area.
Coverage of showers will be limited, with only a few isolated
locations likely to see light precipitation. Temperatures behind the
shortwave will continue to be chilly, with below average
temperatures expected. 700 mb temperatures will hover at or below
0C, leading to highs in the 40s and 50s on Monday. Ample cloud
cover will also contribute to the limited warming expected
throughout the day. However, clouds will begin to clear out
overnight from northwest to southeast. Combined with calm
conditions, certain areas across southeast Wyoming will
effectively cool off from radiational cooling. As a result,
locations west of the Laramie Range and Converse County will
likely cool below freezing early Tuesday morning. Due to this,
went ahead and issued a Freeze Watch for Converse County and
portions of Carbon County that have not yet hit freezing this
season.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
Issued at 319 PM MDT Sun Oct 5 2025

A ridge starts to build into the Intermountain West
Tuesday into Wednesday. This ridge will increase 700mb temperatures
into the 5 to 7C range which will translate our high temperatures
raising into the 60`s and 70`s. There is a weak shortwave that
pushes through the Intermountain West however it looks like the
stronger vorticity stream will just be to north of the Southeast
Wyoming area. So our region looks to stay dry Wednesday. The ridge
strengthens behind the weak shortwave so Thursday and Friday will
remain in the 60`s and 70`s. Overnight temperatures look to remain
in the 30`s and 40`s for the long term period a clear signal that
winter will be here soon. Another trough pushes into the
Intermountain West from the Pacific Northwest this weekend. This
looks to increase the rain chances starting Saturday afternoon and
lasting through the weekend. 700mb temperatures range from 3 to 10c
giving us warmer temperatures into the overnight period (40`s/50`s)
and potentially some 80 degree days into the Nebraska Panhandle.

&&

.AVIATION /06Z TAFS THROUGH 06Z TUESDAY/...
Issued at 1130 PM MDT Sun Oct 5 2025

Upper level trough axis will slowly push through the area Monday,
with much cooler than normal conditions and light to occasionally
moderate rainfall early this morning. Low stratus is expected to
linger across the area through Monday afternoon with some clearing
expected after 00z Tuesday.

HAZARDS/WEATHER TRENDS: Generally MVFR CIGS and VIS in light to
occasionally moderate rainfall across southeast Wyoming and western
Nebraska. KLAR and KCYS will see periods of IFR conditions and low
CIGS with maybe some fog developing after 09z until 15z. Conditions
won`t improve much after sunrise, with low CIGS expected through
Monday afternoon. KRWL will be the first to clear out by 21z, with
KCYS likely lingering through 03z Tuesday.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...Freeze Watch from late Monday night through Tuesday morning
     for WYZ101-104-110-111.
NE...None.

&&

$$

SHORT TERM...SF
LONG TERM...MM
AVIATION...MM