Chadron, Nebraska 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

768
FXUS65 KCYS 211111
AFDCYS

Area Forecast Discussion
National Weather Service Cheyenne WY
511 AM MDT Wed Oct 21 2026

.KEY MESSAGES...

- Above average temperatures will continue through the end of
  the week, but a weekend system will drop temperatures towards
  near- to below-average temperatures.

- Precipitation possible Friday through Sunday, with the
  potential for frozen precipitation outside of the mountain on
  Sunday.

- Another system will try to take shape for mid-week, with the potential
  for additional precipitation and, possibly, high winds.

&&

.SHORT TERM /THROUGH THURSDAY NIGHT/...
Issued at 303 AM MDT Wed Oct 21 2026

Mostly clear skies ongoing tonight across southeast Wyoming and
western Nebraska. A few mid-level clouds are visible on satellite
drifting across Niobrara County with some lower clouds over Carbon,
Sioux, and Dawes counties. Winds are mostly light tonight outside of
Bordeaux with temperatures in the mid-40s and low-50s area-wide.
High-level clouds are starting to surge up from the southeast and are
moving into Wyoming from Utah and Colorado. These high clouds will
continue to push into western portions of the CWA before spreading
eastward throughout the morning and afternoon hours.

Upper-level flow today will remain benign as an upper-level ridge
continues to develop across the central CONUS. Southwesterly flow
will continue across the CWA in the upper-level with the building
ridge. An upper-level low will start to move inland into southern
California during the day, with a stout jet developing. A 500mb
shortwave look to develop and push across western portions of the
CWA this evening, leading to a brief 3 to 6 hour period of enhanced,
dynamic lift. Strong 500mb CVA will help eject this shortwave
through quickly, leading to minimal precipitation chances for most
areas. 700mb flow remains fairly weak from the southwest, though a
700mb shortwave develops with the 500mb shortwave moving through.
With southwesterly upper-level flow, moisture from the Pacific Ocean
will advect into the Intermountain West, leading to increased
moisture mostly west of the Laramie Range in southeast Wyoming. As a
result, with the 500mb and 700mb shortwave pushing through this
evening, a few showers may develop along the Sierra Madre Range this
evening, especially as surface flow turns southwesterly. 700mb
temperatures will remain quite warm this evening, in the 4 to 5C
range across Carbon County, which will prevent any frozen
precipitation from developing along the Sierra Madre Range.
Significant precipitation is not expected today, with total
accumulations remaining around a trace for a small portion of Carbon
County. Temperatures will be well above average once again today,
with highs in the mid-60s to mid-70s, with normal values for this
time of year around the mid-50s to mid-60s.

Thursday will start to become more active as the upper-level low
over western California moves east-northeastward inland towards the
Intermountain West, ending around northern Nevada by Friday morning.
The upper-level will be pushed off to the east as the low moves east-
northeastward, with upper-level flow remaining southwesterly and
increasing across southeast Wyoming and western Nebraska. Several
lobes of 500mb vorticity will eject northeastward from the base of
the upper-level trough, leading to increased synoptic ascent. The
best forcing looks to, once again, remain confined to Carbon County
and areas west of the Laramie Range for Thursday, but this will
change for Friday and the weekend. 700mb flow starts to become more
active as the shortwave ejects northeastward towards South Dakota
and the winds begin to increase with the approaching system. Strong,
southerly flow develops ahead of the approaching system by the
afternoon hours, with flow increasing through the overnight hours.
700mb temperatures will remain quite warm, in the 7 to 9C range, for
much of the area, therefore, any precipitation that falls will
continue to be rain. Precipitation chances across Carbon and Albany
counties will start to increase early Thursday morning and
continuing through the evening hours. Precipitation looks to remain
confined to west of the Laramie Range, where the best ascent and
moisture will be located due to the southwesterly flow advecting in
Pacific moisture and getting trapped along the Laramie Range. There
will be meager CAPE across this region, so a rumble or two or
thunder cannot be completely ruled out, though widespread storms are
not expected. Temperatures will be above average again Thursday with
highs in the low-60s to mid-70s, though overnight lows in the Sierra
Madres may favor some flurries developing with the increased ascent
and moisture in this region. Significant snowfall is not anticipated
at this time for Thursday and Friday morning.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
Issued at 303 AM MDT Wed Oct 21 2026

Active weather continues for Friday as the upper-level low across
northern Nevada continues to push eastwards towards western Wyoming.
A fairly strong, southerly, upper-level jet starts to move overhead
Friday morning as the upper-level low pushes into Utah. With much of
the region downstream of the upper-level trough axis and portions of
the CWA within the left exit region of the jet, synoptic forcing
will increase significantly from previous days. The trough starts to
elongate overnight Friday, per the GFS and ECMWF, with the upper-
level jet strengthening to around 100kts by Saturday morning.
Unfortunately, very strong 500mb cyclonic vorticity advection (CVA)
will develop across Montana, favoring the deepening of the northern
portion of the system. This will lead to split flow developing
across the Intermountain west, with the northern branch remaining
much stronger than the southern branch. The southern branch looks to
be the primary forcing mechanism for precipitation, so as this start
to weaken, precipitation will decrease across the region. Similarly,
the 700mb low will develop Friday morning before pushing
northeastward and starting to elongate with the upper-level system.
This will, once again, push the best forcing off the north with more
modest forcing expected across the CWA and very weak 700mb flow
developing for Saturday morning. Despite the less favorable
evolution of this system, precipitation chances are expected to
increase from southwest to northeast across the CWA Friday morning
through Friday evening. Precipitation will remain mostly rain as
700mb temperatures stay fairly warm in the 5 to 8C range Friday
evening. A strong cold front will accompany this system and will
drop 700mb temperatures into the 0 to 4C range by early Saturday
morning. With cooling temperatures at 700mb, rain across the Sierra
Madre and Snowy ranges should change over to mostly snow overnight
Friday into Saturday morning. Significant snow accumulation is not
anticipated at this time, due to the weakening southern branch of
the system. Temperatures will max out in the upper-50s to low-80s
Friday afternoon, with the warmest temperatures across the western
Nebraska Panhandle due to very strong southerly flow. Overnight lows
will be much cooler, thanks to the incoming cold front, dropping
into the mid-30s to low-50s everywhere.

Saturday turns much cooler as the cold front associated with the
upper-level system moves through the region by mid-day Saturday,
though daytime high temperatures will remain in the mid-40s to mid-
50s everywhere. Upper-level flow remains southerly across the CWA
Saturday as the upper-level low slowly pushes eastward. Some
synoptic ascent will be present Saturday as a few 500mb vorticity
lobes eject northeastward and the region remains downstream of the
trough axis, though this ascent will be weaker as the elongates
southward. Weak, southerly to southeasterly 700mb flow is expected
throughout the day Saturday as the 700mb flow get absorbed. 700mb
temperatures will hover in the 0 to 2C range, with a few areas
expected to see 700mb temperatures drop below 0C. Precipitation
chances will decrease throughout the day Saturday as the best
forcing weakens and moves away. Despite this, long range models are
starting to suggest that a surface low will develop over
southeastern Colorado Saturday evening into the early morning hours
Sunday. Precipitation associated with this potential system would
eject northeastward towards the CWA and collide with the backdoor
cold front expected to swing into the region Saturday evening into
the overnight hours. This collision could result in a favorable area
for precipitation to develop across much of the CWA, especially
western Nebraska.

On Sunday, the upper-level low is progged to get absorbed into the
upper-level flow and finally push the upper-level trough through the
Intermountain West by Monday morning. The backdoor, 700mb cold front
looks to push through the Sunday morning hours, dropping 700mb
temperatures to between -2 and 0C throughout the day Sunday. With
the cold front potentially still colliding with the moisture push
from the surface low across southeastern Colorado, precipitation
chances may remain in place across the region. However, with 700mb
temperatures currently progged to be between -2 and 0C,
precipitation could change over to snow for much of the area, but
especially southeast Wyoming along and east of the Laramie Range.
There is still some uncertainty in this, though long range models
remain in fairly good agreement on the propagation of this system.
If this hold together, snow flurries could be flying across much of
the CWA Sunday, though ground temperatures will likely remain too
warm for accumulating snowfall.

Long range models start to disagree at the beginning of the work
week, with the GFS suggesting a strong upper-level low diving
southward out of Canada into the northwestern CONUS. The GFS suggest
this low strengthening and moving west to east across Montana,
leading to a 250mb, westerly jet around 100kts across the CWA by
midweek. The ECMWF suggests a similar evolution though slower and a
touch weaker than the GFS solution, with a broader upper-level
trough compared to the amplified upper-level low in the GFS. The
700mb flow follows a similar pattern in the long range models,
suggesting a westerly, low-level jet across the CWA by mid-week.
This could result in a high wind event for some of the wind prone
regions by Wednesday, but confidence is low at this time.

&&

.AVIATION /12Z TAFS THROUGH 12Z THURSDAY/...
Issued at 510 AM MDT Wed Oct 21 2026

Mostly quiet conditions expected for the 12Z TAF period. High
clouds will move in this afternoon with winds remaining fairly
light, around 10kts. Isolated showers could move into KRWL and
KLAR as early as 00Z, with increasing chances after 00Z.

&&

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

&&

$$

SHORT TERM...AM
LONG TERM...AM
AVIATION...AM