791
FXUS65 KCYS 011743
AFDCYS

Area Forecast Discussion
National Weather Service Cheyenne WY
1143 AM MDT Sat Nov 1 2025

.KEY MESSAGES...

- Locally strong gusty winds return to the wind prone areas of
  southeast Wyoming Saturday night into Sunday.

- Warmer and continued dry conditions are expected through the
  weekend. A short-lived cool-down is on track for Monday.

&&

.SHORT TERM /THROUGH SUNDAY NIGHT/...
Issued at 136 AM MDT Sat Nov 1 2025

Mid level water vapor is showing a river of dry air on the backside
of the trough over the Northern Plains/Midwest. THe dry air is
advecting in from Canada and filtering through as Northerly flow
prevails. This river of dry air will be helping to keep the skies
clear throughout the day. Over the course of the day an upper level
ridge will be pushing into the Intermountain west from the West
coast. 700mb temperatures look to increase from tonight`s -8 degrees
to +10C by Sunday afternoon increasing the high temperatures into
the 60 and 70`s this weekend with the warmer temperatures occurring
Sunday afternoon.

A surface high is expected to set up in Northwest Colorado and
strengthen over the course of the day Saturday. This surface high
will increase/tighten the MLSP gradient this afternoon. Aloft, 700-
mb winds have increased slightly from the previous model runs
hitting between 50- 56 knots as the MLSP gradient tightens on the
surface. Looking at the GFS, the 700mb jet isn`t progged to maintain
the 50-56knot intensity for very long creating some doubt if we will
hit high wind criteria Saturday evening into Sunday morning.
However, our in house wind algorithm increases the probabilities from
40 to 60 percent of reaching our high wind criteria from 06z to 18z
Sunday in our wind prone areas. Confidence is high in gusty winds
occurring overnight but due to the short window of those stronger
winds in the 700mb jet, the watch won`t be upgraded this shift.
Winds are expected to die back down Sunday evening.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
Issued at 330 PM MDT Fri Oct 31 2025

Precipitation chances will remain fairly limited through the week
ahead. On Monday, a weak shortwave riding over top of the ridge
aloft will drop a surface cold front through the area. Monday`s
highs will be 10-20F cooler than Sunday east of the Laramie Range,
while those west will be similar or just slightly cooler as the
surface high pressure moves through the area. The ridge is expected
to recover and support a return to above average temperatures on
Tuesday, but yet another shortwave passing to the north will knock
temperatures down again for Wednesday. Westerly flow returns for
Tuesday also, but the probabilities for high winds are fairly low
(25%) at this time.

A more potent trough is expected to traverse across the Rockies
around the Thursday time period. Guidance has begin to come into
better agreement showing this feature tracking just to our north
now, with most ensembles showing us in the drier, windier sector.
Precipitation chances will return for the mountains and areas along
and west of the Laramie range, but the probability for snow impacts
to the High Plains remains low. There is only about a 10% chance for
measurable precipitation east of I-25 (a little higher near
Douglas). However, nearly half of ensemble members are already
showing 700-mb winds exceeding 50 knots sometime in the
Thursday/Friday period, lending support for another period of high
wind potential. However, at 6-7 days out, confidence remains low.
Winds were nudged towards the NBM 75th percentile during this period
to account for the possibility, but did not get too aggressive with
it yet.

&&

.AVIATION /18Z TAFS THROUGH 18Z SUNDAY/...
Issued at 1140 AM MDT Sat Nov 1 2025

VFR conditions expected over the next 24 hours. High clouds
should begin breaking up this afternoon, but expect them to
linger until this evening. Winds will be mostly breezy today and
again tomorrow morning into the afternoon with gusts generally
in the 20-35 knot range. A strong jet overhead will bring
enhanced low level wind shear to all sites except for KRWL, with
speeds around 40 knots or so in difference at around 2K feet.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...High Wind Watch from late tonight through Sunday afternoon for
     WYZ106-116-117.
     High Wind Watch from 9 PM MDT this evening through Sunday
     afternoon for WYZ110.
NE...None.

&&

$$

SHORT TERM...MM
LONG TERM...MN
AVIATION...CG