Chadron, Nebraska 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

679
FXUS65 KCYS 240817
AFDCYS

Area Forecast Discussion
National Weather Service Cheyenne WY
217 AM MDT Mon Aug 24 2026

.KEY MESSAGES...

- Daily shower and thunderstorm chances continue Monday through
  the end of the week with slightly above average temperature
  expected until Thursday.

- Showers and Thunderstorms Monday afternoon may produce strong
  gusty winds over southeast Wyoming and western Nebraska
  through this evening.

- Near average temperatures through Wednesday, with a slight
  warming trend late this week and into the weekend.

&&

.SHORT TERM /THROUGH TUESDAY NIGHT/...
Issued at 210 AM MDT Mon Aug 24 2026

Current KCYS radar loop shows some lingering showers and
embedded thunder across central and south central Wyoming early
this morning. Not much forcing in the area, so activity is
likely due to remnant outflow boundaries and convection west of
the area from Sunday afternoon. Expect this activity to
dissipate over the next few hours with relatively quiet
conditions expected early Monday morning.

Similar convective environment this afternoon in comparison to
Sunday, but with more midlevel forcing and a bit more low level
convergence along the Laramie Range and the southeast Wyoming
eastern plains as a cool front dips south into the region later
this afternoon. A poorly defined dry-line will also drift east
today as westerly winds increase slightly ahead of the front.
These factors should be enough to initiate high based convection
for much of the area, especially southeast Wyoming and far
western Nebraska. Models show inverted V soundings across most
of the region into the afternoon, but a few locations in and
around Sidney, Alliance, and Chadron continue to show 800 to
1600 j/kg of MLCAPE with marginal shear values around 25 to 30
knots. Initially, expect most of the convection to produce
strong gusty winds...even without any thunderstorms due to the
dry boundary layer up to 500mb. Once we head into the late
afternoon and evening hours, the surface cool front will push
south towards the I-80 corridor and North Platte River Valley.
Expect a better chance of rain showers and thunderstorms during
this time period, so kept POP between 25 to 40 percent into the
late evening hours. The Marginal Risk for severe thunderstorms
remains over the whole forecast area, mainly for strong gusty
winds between 55 to 70 MPH. Further east, SPC has introduced a
Slight Risk where the more favorable convective environment is
located. Portions of western Nebraska may also see some
marginally large hail and strong winds over 65 MPH this
afternoon through later this evening. Some of this convection
may linger past midnight as moisture advection and some jet
energy aloft remains over the area through Monday night.

Weather becomes more active starting on Tuesday as models show
another potent shortwave, embedded in northwest flow aloft,
digging southeast across the I-25 corridor and the eastern
plains. Thankfully, 0-6km shear relaxes a bit behind the front
with shear values mainly below 25 knots. Heavy rainfall looks to
be more of a concern due to slow storm motion/weak winds
aloft...with a Marginal Risk for Excessive rain, especially
near the Colorado border. Cooler temperatures are also expected
with high temperatures around 80 to maybe 85 degrees east of the
I-25 corridor. Increased POP up to 50 percent for high-end
scattered thunderstorms near the I-80 corridor. May need to
extent the highest coverage of thunderstorms further east into
the southern and central Nebraska Panhandle depending on low
level stability and the amount of CIN. However, the opposite may
present a problem as well, and may need to lower POP across the
area if low clouds and CIN are too strong along and east of the
Laramie Range. For now, will continue to monitor and update as
needed.

&&

.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
Issued at 252 PM MDT Sun Aug 23 2026

No major changes to the overall long term forecast as we see
conditions slightly warmer than average to start the period and
then by the end of the week into next weekend we warm back up to
several degrees above average with monsoonal moisture providing
a daily chance of thunderstorms with a low end severe risk
generally expected each day. At the upper levels, a strong ridge
of high pressure will control the Western US, and should
continue to hold control until the end of the week when a deep
low will approach the western Canadian coastline. This feature
may begin to move inland and could interrupt our pattern by late
next weekend, but until then expect largely similar conditions
each day. Moisture at the surface may begin to slowly dwindle,
and by the late week into the weekend elevated fire weather
concerns may begin to arise as minimum daytime RH values drop
back into the teens. Still, daily PWAT values will sit around
120-130% of normal, and between daytime instability and weak
disturbances riding the periphery of the ridge, we should still
see thunderstorm chances each afternoon with a low end severe
threat possible. At the surface meanwhile, a cold front will
stall out on Tuesday and then begin advancing back eastwards as
a warm front but should become very slow moving to even
stationary, helping to fuel storm initiation through the end of
the week. Overall it will be more of the same as we remain in a
fairly stagnant pattern through the period.

&&

.AVIATION /06Z TAFS THROUGH 06Z TUESDAY/...
Issued at 1122 PM MDT Sun Aug 23 2026

VFR conditions will prevail across all terminals for the duration of
this TAF period. An exception may be where a shower and/or
thunderstorm comes near or over a site, reducing CIGs and VIS
briefly to possibly MVFR or lower if a storm becomes intense. So,
confidence isn`t high in timing and coverage, so PROB30 groups have
been introduced for the Nebraska Panhandle terminals and VCSH for
the southeast Wyoming sites. Ample time to fine tune the forecast
before Monday afternoon`s activity. Relatively weak winds overnight
with them ramping back up after about 18Z Monday ever so slightly.
Expect gusty and erratic winds in and near any shower and/or
thunderstorm activity that occurs Monday afternoon.

&&

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

&&

$$

SHORT TERM...TJT
LONG TERM...CG
AVIATION...RZ