Chadron, Nebraska 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

145
FXUS65 KCYS 231147
AFDCYS

Area Forecast Discussion
National Weather Service Cheyenne WY
545 AM MDT Wed Sep 23 2026

.KEY MESSAGES...

- Cool but seasonable temperatures will continue through mid-
  week, with a warming trend expected for the weekend.

- Increasing coverage of showers and thunderstorms expected
  through Thursday as a subtropical disturbance lifts northward
  over the area, then a brief drying trend for the weekend.

&&

.SHORT TERM /THROUGH FRIDAY/...
Issued at 200 AM MDT Wed Sep 23 2026

Current KCYS radar loop shows several bands of rain showers and
embedded thunderstorms across the area, with the main cluster
moving northeast and weakening across the northern NE
panhandle, and a secondary band over the mountains and moving
into the high plains near I-25 early this morning. A bit higher
coverage than what was previously expected since the upper level
trough seems to be initializing further east than what models
were showing yesterday, but forecast generally remains on track
this morning with some minor tweaks to precip coverage through
sunrise. Did add some patchy fog to portions of the high plains
of southeast Wyoming and western Nebraska since a few places
did receive some decent rainfall amounts from the thunderstorm
activity yesterday evening. Expect showers to become more
isolated around sunrise as the upper level trough lifts
northeast into the Dakotas with some drier air temporarily
moving into southeast Wyoming for Wednesday afternoon.

Models are starting to come into better agreement for today and
Thursday with rainfall and thunderstorm chances, although
confidence is still limited. The northern Front Range will be
in-between systems today as we`ll be watching the next
subtropical disturbance lifting northward out of New Mexico.
This is the same system that is aiding in the development of
excessive rainfall and flooding across far western Texas and
southern New Mexico over the last 24 hours. This disturbance is
forecast to lift northward slowly today and gradually into
southern Colorado by tonight. For today, expect near average
temperatures in the 70s to near 80, warmest north of Interstate
80. Since we`re in-between weather systems, shortwave ridging
will temporarily limit convection today. Kept POP between 20 to
40 percent for most of western Nebraska, where the best moisture
profiles will be located, and across far southern Wyoming where
some moisture advection and instability is noted as we head
into the afternoon hours. High res models do show widely
scattered to scattered showers and thunderstorms moving eastward
across the high plains, generally along and east of the Laramie
Range. Some gusty winds and brief heavy rainfall possible, but
strong to severe thunderstorms are not expected.

Models have trended less aggressive on Thursday regarding the
subtropical upper level disturbance, mainly because models have
trended slower with the vort max/midlevel energy. The 00z GFS
still shows a southwest to northeast trajectory of the system
with limited impacts over the forecast area. The Canadian and
ECMWF show the disturbance lifting northward very slowly into
Wyoming Thursday night instead of Thursday afternoon. Generally,
there will be less instability and limited forcing to work with.
Although there is still a good chance for widespread rainfall,
lighter amounts are expected with moderate amounts in and near
thunderstorms. QPF amounts have been adjusted lower with the
highest amounts between a quarter inch to maybe a half inch from
the I-80 corridor towards the lower North Platte River Valley
through Thursday night. However, will continue to monitor the
timing of this disturbance, since NAEFS continue to show
PWATs/low to midlevel moisture above the 99th percentile if
climatology for late September and early October.

All models show drier air moving into the region on Friday as
low to midlevel winds shift into the west and dewpoints lower
into the 30s and low 40s across most of southeast Wyoming.
Surface moisture will remain over western Nebraska, but limited
forcing and instability should greatly inhibit convection this
time of the year. Kept POP below 25 percent with a lower
coverage of showers and thunderstorms expected, mainly over the
northern Panhandle of NE and the mountains of southeast Wyoming.
Temperatures will begin to rebound after a relatively cool
Thursday with high temperatures back into the 70s to near 80,
warmest below elevations of 4500 feet.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
Issued at 220 PM MDT Tue Sep 22 2026

Saturday...Pleasant early autumnal weather continues with dry
westerly flow aloft and relatively low precipitable water values,
PWAT. 700 mb temperatures near 13 Celsius suggest mild late
September maximum temperatures.

Sunday...Outdoor enthusiasts that like mild early Autumn like
weather will be pleasantly surprised under dry southwest flow aloft
and weak low level southeast winds. Continued mild with 700 mb
temperatures near 11 Celsius.

Monday...Another moisture plume develops from Arizona and New
Mexico, northeastward to southern Wyoming and western Colorado on
strengthening southwest flow aloft. With a low level surface trough
developing from western South Dakota to eastern New Mexico, and a
series of shortwave troughs aloft moving overhead, expect to see an
increase in areal afternoon and evening shower and thunderstorm
coverage, especially across our Snowy and Sierra Madre Ranges due to
orographic lift on moist southwest flow aloft.

Tuesday...Confidence in synoptic pattern is low to moderate as this
is, after all, day seven. However, it looks like some form of
troughiness aloft will reside across Wyoming and Colorado with the
moisture plume extending from western Colorado to western Nebraska,
and daytime heating and low level convergence is likely to set off
at least widely scattered to scattered showers and thunderstorms in
the afternoon and evening, and we may need to see POPS boosted if
model trends continue.

&&

.AVIATION /12Z TAFS THROUGH 12Z THURSDAY/...
Issued at 545 AM MDT Wed Sep 23 2026

Low stratus clouds and some patchy fog will continue until shortly
after sunrise across the eastern plains terminals. Mostly cloudy
skies for much of the day with another round of widely scattered
showers and thunderstorms possible this afternoon and into
this evening.

HAZARDS/WEATHER TRENDS: IFR to LIFR CIGS will continue until 15z or
16z with intermittent fog over KAIA and KBFF. Can`t rule out
redevelopment for KSNY and KCYS again early this morning but
confidence is relatively low (30%). Otherwise, BKN to OVC midlevel
cloudiness expected over the next 24 hours with another round of
showers and thunderstorms for mainly KCYS, KBFF, and KLAR after 20z
with brief MVFR VIS possible through 02z Thursday.

&&

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

&&

$$

SHORT TERM...TJT
LONG TERM...RUBIN
AVIATION...TJT