Cheyenne, Wyoming 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

265
FXUS65 KCYS 222338
AFDCYS

Area Forecast Discussion
National Weather Service Cheyenne WY
438 PM MST Mon Dec 22 2025

.KEY MESSAGES...

- High Wind Warnings are in effect for the wind prone zones of
  southeast Wyoming through 5pm this afternoon.

- Red Flag Warnings are in effect for central and eastern
  Laramie County due to low RH values and gusty winds through
  5pm this afternoon.

- Record breaking warmth is expected to continue through at
  least Thursday.

- Strong gusts alongside more record warmth expected on
  Christmas Day, followed by temperatures cooling slightly by
  next weekend.

&&

.SHORT TERM /THROUGH TUESDAY NIGHT/...
Issued at 242 PM MST Mon Dec 22 2025

Trust me, the winds will eventually die down this evening. But
first, there are a couple other things we are monitoring,
temperatures and fire weather concerns. So, lets start off
talking about the near record or record temperatures we are
seeing across the CWA this afternoon. Yep, it doesn`t really
feel like the latter part of December. An indicator of how warm
surface temperatures will get, we look at the 700mb temps, and
guidance is indicating very anomalous warmth aloft. This coupled
with downsloping winds make the perfect combination for the
potential of record warmth across the CWA, especially east of
I-25. So, what are the temperatures we can see in this short
term period? Expect highs today to soar into the 60s to low 70s
primarily east of I-25 and only in the 50s to the west. Lows
tonight will only dip into the low to mid 30s. Tuesday will be a
rinse repeat type of day for temperatures. A lot of this is
also due to an upper level ridge that slides across the CWA
today and will be a major factor our weather here locally, with
the temperatures mentioned above and the continuation of dry
conditions. So, don`t expect that white Christmas we all, or
most, want as we wake up Christmas morning.

With the temperature and precipitation talk out of the way, lets
talk about winds. A strong surface gradient with appropriate
subsidence continues to bring us gusty winds to our known wind
prone areas, those along I-25 and I-80, and into Cheyenne. So,
High Wind Warnings remain in effect until 5pm this afternoon for
Bordeaux, Rawlins, and the Laramie Summit/Foothills through 5pm
this evening. As it was mentioned at the start of this
discussion, these winds will weaken through this
afternoon/evening as the surface gradient laxes along with the
700mb jet weakening.

Another major thing we continue to monitor, one could argue the
most import thing, is the fire weather concerns. With dry
grasses and dry conditions along with gusty winds, fire weather
concerns are high. With minimum RH values in the 15-20% range
and winds gusting upwards of 50-55 mph, Red Flag Warnings are
out for Central and Eastern Laramie County through 5pm this
afternoon. This coincides with the SPC and their critical
declaration for the Fire Weather Outlook, some collaboration was
done as well. For Tuesday, fire weather concerns are still
present; however, RH values will be ever so slightly higher and
winds will be much weaker then today. So, as of this discussion,
we don`t have any Red Flag Warnings out for Tuesday, but this
will be closely monitored in subsequent shifts.

&&

.LONG TERM /WEDNESDAY THROUGH MONDAY/...
Issued at 242 PM MST Mon Dec 22 2025

Mild, record-breaking temperatures will continue through mid-week as
strong upper-level ridging continues to sit over most of CONUS.
Christmas Eve and Christmas will feel more like Memorial Day with
high temperatures in the 50s and 60s and potentially even low 70s
for lower elevation areas. Southwest winds aloft will advect warm
air into the CWA, allowing 700 mb temperatures to warm up to +6C.
For much of Christmas Eve and Christmas, 700 mb temperatures will be
above the 90th percentile of NAEFS climatology. Downsloping winds
will also contribute to the warmth. As a result, climate sites
across the forecast area are likely to either tie or break their
record highs on both Christmas Eve and Christmas. While Christmas
Eve will be quiet weather-wise, a shortwave moving in early
Christmas morning could bring some light snow to the mountains and
some light rain to some of the adjacent valleys. Cannot rule out a
rumble of thunder out west as model soundings do show a bit of
surface instability! Little snow accumulation is expected. This
shortwave will likely also briefly bring high winds to the usual
southeast Wyoming wind prones Christmas morning as MSLP gradients
tighten.

A pattern change arrives Friday as a cold front ushers in cooler,
but less windy conditions. A weak Pacific trough will move into the
CWA, pushing a cold front through the area during the day Friday.
There will be some precipitation with the front, however it will
mainly stick to the mountains and areas out west. Mountain snow
accumulation is likely with a dusting possible in the adjacent high
valleys. Saturday and Sunday, lingering snow showers could be
possible, however drier conditions overall are expected.
Temperatures over the weekend will fall to average for the end of
December, with highs in the 30s and 40s.

&&

.AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/...
Issued at 427 PM MST Mon Dec 22 2025

VFR conditions are expected for the forecast period. Gusty winds
will ease over the next few hours (except at KRWL) and should be
light for the most part overnight. However, LLWS will linger
after midnight in Wyoming. Wind gusts return mid Tuesday
morning, but they should be lighter than today. Expect gusts 30
to 40 knots at KRWL, 20 to 30 knots at KLAR, and 15 to 25 knots
elsewhere.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...High Wind Warning until 5 PM MST this afternoon for WYZ106-109-
     110-115>118.
     Red Flag Warning until 5 PM MST this afternoon for WYZ430-431.
NE...None.

&&

$$

SHORT TERM...RZ
LONG TERM...SF
AVIATION...MN