711
FXUS65 KCYS 221124
AFDCYS

Area Forecast Discussion
National Weather Service Cheyenne WY
524 AM MDT Wed Jul 22 2026

.KEY MESSAGES...

- Widespread showers and storms are expected over the next
  several days. Monsoon moisture will lead to heavy rain with
  the potential for flash flooding. Isolated severe storms will
  also be possible.

&&

.SHORT TERM /THROUGH THURSDAY NIGHT/...
Issued at 204 AM MDT Wed Jul 22 2026

Showers and storms continue early this morning, but radar trends
show decreasing coverage and intensity of storms. Any shower
activity will likely be done by sunrise so that the atmosphere can
once again prime itself for another round of showers and storms
Wednesday afternoon. Temperatures will quickly warm during the
morning hours, allowing instability to build across the area. Model
soundings look a bit more promising today for heavy rainfall and
even an isolated severe thunderstorm or two. PWATs will rise into
the 99th percentile for much of the CWA as south to southwest flow
continues to drive monsoon moisture into southeast Wyoming and
western Nebraska. Cloud layer winds are rather slow across Wyoming,
so heavy rain and flooding potential will remain the primary
threats in any storms on Wednesday. Storms will move faster
across Nebraska, however, with PWATs approaching almost 1.50
inches, flash flooding will still be the biggest concern. There
is some decent instability across the panhandle, so cannot rule
out an isolated severe storm with either strong gusty winds, or
brief large hail. Hi-Res guidance shows storms continuing
through about midnight, with some lingering showers possible
after that.

Thursday will basically be a repeat of Wednesday, albeit with
better parameters. PWATs will reach NAEFS climatological max
with cloud layer winds roughly the same as Wednesday. This
likely means an even greater potential for heavy rains and
flash flooding. Instability will also be about the same,
especially across the Nebraska panhandle, so an isolated severe
storm or two could be possible. Hi- Res guidance shows a little
less coverage of storms across the area, with precipitation
once again continuing into the evening hours.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
Issued at 202 PM MDT Tue Jul 21 2026

Friday...Will see an abrupt cutoff to the low and mid level moisture
supply as drier air at low and mid levels advects into our counties
as the dominant ridge over Colorado and southern Wyoming reasserts
itself. Thus dry and hotter.

Saturday through Tuesday...Isolated to scattered afternoon and
evening showers and thunderstorms expected, with areal coverage
increasing each day due to increased mid level moisture.
Fortunately, more beneficial rains expected concentrated over and
near our Snowy, Sierra Madre and Laramie Ranges, with the best
chances for convection on Monday and Tuesday. Typical weak northwest
flow aloft on the northeast periphery of the ridge aloft will aid in
occasional passing shortwave troughs aloft near peak heating
resulting in increasing convective potential each day

&&

.AVIATION /12Z TAFS THROUGH 12Z THURSDAY/...
Issued at 523 AM MDT Wed Jul 22 2026

The main aviation concern today will be scattered showers and
thunderstorms with heavy rain. Storms will likely develop during the
afternoon and evening for southeast Wyoming terminals. Slow moving
storms will drop heavy rain that could reduce visibility down to
MVFR or IFR criteria. Storms will move into the Nebraska panhandle
later in the evening, with heavy rain and reduced visibility still
expected to be the main impact. Strong wind gusts will also be
possible with storms. Low CIGs and patchy fog will be possible
Thursday morning from the increased moisture.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...None.
NE...None.

&&

$$

SHORT TERM...SF
LONG TERM...RUBIN
AVIATION...SF