Chadron, Nebraska 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

427
FXUS65 KCYS 210824
AFDCYS

Area Forecast Discussion
National Weather Service Cheyenne WY
224 AM MDT Tue Jul 21 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 WEDNESDAY NIGHT/...
Issued at 220 AM MDT Tue Jul 21 2026

Lift from a cold front that moved across the area earlier has lead
to continued shower and thunderstorm activity early this morning.
Storms are not moving particularly fast, allowing some decent
rainfall accumulations. Hi-Res guidance does suggest showers and
storms dissipating around sunrise, with a small lull in activity
before storms once again develop early in the afternoon. Moist south
to southwest flow will drive ample monsoon moisture into the CWA
throughout the day. PWATs will rise into the 90th percentile as a
result. Vorticity maxes aloft will aid in sparking convection across
the area. Hi-Res guidance has storms developing early in the
afternoon off the high terrain, gradually pushing eastward through
the afternoon and into the evening hours. Model soundings do show
cloud layer winds to be on the slower side, meaning storms today
will be slow moving. The combination of high PWATs and slow storms
will lead to heavy rain and the potential for flash flooding.
Cannot rule out an isolated severe thunderstorm or two as there
are pockets of elevated instability across both southeast
Wyoming and western Nebraska. Storms will become more numerous
and widespread by the evening hours, but will start to weaken
and decrease in coverage by midnight.

Wednesday will basically be a repeat of Tuesday, albeit with
better parameters. PWATs will reach the 99th percentile with
even slower cloud layer winds meaning an even greater potential
for heavy rains and flash flooding. Instability will be higher,
especially across the Nebraska panhandle meaning a better
likelihood for severe thunderstorms. Hi-Res guidance shows
greater coverage of storms across the area, with precipitation
once again continuing well into Wednesday night.

&&

.LONG TERM /THURSDAY THROUGH MONDAY/...
Issued at 1229 PM MDT Mon Jul 20 2026

Thursday...More beneficial rains are anticipated as a decent
positively tilted shortwave trough aloft passes overhead near peak
heating, and with beaucoup...plenty of low and mid level moisture
and decent upslope southeast winds advecting low level moisture
northwestward, expect to see numerous to widespread showers with
scattered thunderstorms in the afternoon and evening, focused once
again along the I-25 corridor and near the mountains where
orographics will coincide with the best 850/700 mb theta-e ridge
axis.

Friday...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 Monday...Isolated to scattered afternoon and
evening thunderstorms expected, with areal coverage increasing each
day due to increased mid level moisture. Fortunately, more
beneficial rains expected concentrated south of a Rawlins to
Scottsbluff line and over and near the Snowy, Sierra Madre and
Laramie Ranges. Typical weak northwest flow aloft on the northeast
periphery of the ridge aloft will aid in occasional passing
shortwave troughs aloft near peak heating.

&&

.AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/...
Issued at 1115 PM MDT Mon Jul 20 2026

Continued scattered shower activity is evident on regional
radars. This activity is not widespread enough to warrant
including as a group in TAFs and is expected to diminish as the
night progresses. Winds are variable and light at most
terminals, but KLAR and KSNY are gusting to 25 knots out of the
east. No MVFR CIGs are expected through tomorrow afternoon. In
the early afternoon hours showers and thunderstorms are expected
to start near KRWL and spread in coverage eastward through the
afternoon and evening. Based on current trends and confidence in
coverage in model guidance, prob30 group were added/kept to
southeast Wyoming terminals. These cover tomorrow afternoon
through the end of the forecast period. Some of these storms
could produce strong winds to 45 knots or greater, lightning,
and heavy rain at terminals. Outside convection the prevailing
winds are out of the southeast between 10 to 20 knots.

&&

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

&&

$$

SHORT TERM...DS
LONG TERM...RUBIN
AVIATION...RV