Chadron, Nebraska 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

594
FXUS65 KCYS 281148
AFDCYS

Area Forecast Discussion
National Weather Service Cheyenne WY
545 AM MDT Fri Aug 28 2026

.KEY MESSAGES...

- There is a Marginal Risk (Level 1 of 5) for severe weather on
  Friday with damaging winds (60+ mph) and large hail (1+ inch)
  possible with the strongest storms.

- There is a Marginal Risk (Level 1 of 5) for severe weather on
  Saturday with strong, damaging winds (70+ mph) and large hail
  (1+ inch) as the primary hazards.

- Slightly above average temperatures, breezy conditions, and
  lower coverage of thunderstorms expected by the middle of next
  week.

&&

.SHORT TERM /THROUGH SATURDAY NIGHT/...
Issued at 137 AM MDT Fri Aug 28 2026

Upper-level ridging will amplify this afternoon into the early
evening hours before starting to tilt northeasterly through the
overnight hours into early Saturday morning. These changes are
caused by a stout, upper-level trough starting to move into the
Pacific Northwest, forcing the ridge eastward and tilting the apex
towards the northeast. Northwesterly flow aloft will turn westerly
then southwesterly between 15 and 03Z today with a fetch of
southwesterly flow from the Pacific Ocean developing. The 500mb high
that has been circulating around the Four Corners region will start
to be pushed easterly between 21 and 03Z as the upper-level flow
becomes dominated by the incoming upper-level trough. A few lobes of
500mb vorticity will advect into the CWA through the morning and
afternoon hours before becoming cutoff from the 500mb high early
Saturday morning. 700mb flow remains westerly across much of the
region with southwesterly flow expected over Carbon County. A
shortwave trough will traverse through the region from 21 to 03Z
this afternoon and evening, bringing with it increasing 700mb height
gradients and a stronger low-level jet. Modest 700mb warm air
advection will accompany the shortwave between 21 and 03Z. GFS omega
fields suggest some downward omega values along and east of the
Laramie Range, acting to dry out the surface with downslope warming
and drying. Not only will downslope warm and dry out the surface, it
will likely prevent significant showers and thunderstorms from
forming this afternoon. Currently there is around a 25 to 40% chance
of showers and storms forming this afternoon. While some of this
precipitation may reach the ground, there will be an increased
threat of gusty showers due to the dry surface with an Inverted-V
sounding in forecasts from the RAP. Most of the instability will
remain off to the east where moisture will be higher. With DCAPE
over 1300 J/kg, gusty showers will be likely this afternoon. The
Storm Prediction Center has just introduced a Marginal Risk (Level 1
of 5) for severe weather today with the primary hazards being
damaging winds (60+mph) and isolated, large hail across western
Nebraska (1+ inches). With the brief strengthening of the ridge
overhead, surface temperatures will be quite warm, in the mid-80s to
low-100s. With downslope drying, afternoon humidity values will be
in the 15 to 25 percent range, leading to elevated fire concerns.
Luckily, winds look to remain below critical thresholds, despite the
gusty conditions anticipated in western portions of the region.

Upper-level ridging will finally push east out of the region on
Saturday as the incoming, upper-level trough forces a more dynamic
pattern in the western CONUS. Strong, southwesterly flow will
develop in the upper-levels Saturday afternoon as the upper-level
trough approaches the region and height gradients increase as the
ridge is slower to move off. An 85 to 90kt jet streak is anticipated
to develop across north central Wyoming by 21Z, leading to portions
of the region placed in the right entrance region of this jet, a
favorable location for dynamically-induced lift. The upper-level jet
will continue to get stronger through Saturday night into early
Sunday morning as the trough digs into the Pacific Northwest and
Intermountain West. Southwesterly 500mb flow will keep the fetch of
moisture from the Pacific Ocean in place throughout the day, with
stronger and larger vorticity maxima traversing through from
southwest to northeast. Southwesterly flow will continue at 700mb
with the low-level jet strengthening around 21 to 03Z before
decreasing in magnitude overnight and increasing again for Sunday
morning. A diffuse 700mb shortwave will move overhead between 21 and
03Z, leading to low-level lift across the region. A surface low
pressure system will develop ahead of the main system across western
South Dakota, increasing surface pressure gradients and bringing a
weak cold front through the region, acting to initiate convection in
the afternoon hours. Convective parameters look better for Saturday,
especially with the increased forcing across the region. Forecast
soundings from the RAP suggesting SBCAPE around 1400 J/kg with
MLCAPE around 700 J/kg. DCAPE remains strong, due to drier
conditions at the surface, around 1000 J/kg. Bulk shear increasing
to around 30kts with favorable speed shear throughout the
atmosphere. Severe weather could be possible, though the primary
threat at this time looks to be damaging winds. The Storm Prediction
Center has placed portions of the region within a Marginal Risk
(Level 1 of 5) for severe weather Saturday afternoon with an
intensity level 1 for the wind threat. This means that storms that
do form in the afternoon could produce wind gusts over 70mph, though
coverage may be lower. Surface temperatures will be warm once again,
in the low-80s to mid-90s.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
Issued at 137 AM MDT Fri Aug 28 2026

Active weather pattern likely to continue Sunday into early
next week as Pacific jet energy and an associated upper level
disturbance moves northeast across Colorado and Wyoming later on
Monday. Models show an 100 knot jet max lifting north across
the Pacific NW region and mainly near the Wyoming and Montana
border Sunday afternoon. This jet is associated with a pretty
strong upper level trough moving eastward near the US and
Canadian border, which may bring some early season snowfall to
the mountains across Montana and the Yellowstone area. This jet
max is forecast to clip the area with models showing decent
upper level difluence. Convective parameters looks suitable for
widely scattered or scattered thunderstorms along the I-80
corridor, and more isolated north of I-80 as some drier air
enters Carbon, Converse, and Niobrara county. MLCAPE between 400
to 800 j/kg and straight hodographs with 30-40 knots of shear
favor linear segments and locally strong gusty winds. MLCAPE and
SBCAPE are closer to 1500 j/kg across portions of western
Nebraska, so the central and southern Panhandle have the higher
potential to see a few strong to severe thunderstorms Sunday
afternoon and evening. Sunday afternoon will also be pretty
windy with the upper level trough not far too our north...expect
wind gusts of 35 to 45 MPH, mainly north of I-80. For Monday,
severe weather is not expected with lower CAPE values and too
much midlevel shear (60+ knots). However, with an upper level
disturbance lifting northeast out of the desert SW, another
round of showers and thunderstorms are possible. This will
greatly depend on the speed and location of the disturbance. The
ECMWF is currently more progressive with the shortwave feature,
showing it moving into the area nearly 6 to 12 hours earlier
compared to the GFS and Canadian. Increased POP up to 50% for
the I-80 corridor with ensembles showing some pretty good total
QPF amounts, but kept POP lower further north towards the North
Platte River Valley. Temperatures will be seasonable with highs
in the upper 70s to upper 80s, but also noticeably cooler
compared Friday and Saturday.

For the rest of next week, all models show southwest flow aloft
developing over the Front Range as a series of late summer fall-
like cold fronts move into the Pacific NW coast and as far south
as northern California. Not expecting this cooler air to make
it into Wyoming this early, but breezy conditions are expected,
especially across southeast Wyoming, with temperatures a few
degrees above average for early September with highs in the mid
70s to mid 80s for southeast Wyoming, and around 90 for western
Nebraska. Precipitation is uncertain since models are struggling
to resolve a pair of shortwaves on the southeastern quadrant of
the main upper level trough near the Pacific coastline. With
timing highly uncertain, POP were kept between 10 to 20 percent.
Ensembles do not show PWATs lowering substantially next week,
so can`t rule out at least isolated convection across the area.

&&

.AVIATION /12Z TAFS THROUGH 12Z SATURDAY/...
Issued at 545 AM MDT Fri Aug 28 2026

Upper level ridge axis will drift east over the area today with
increasing westerly winds across southeast Wyoming. Rain showers and
widely scattered thunderstorms will develop across the mountains and
push east across the high plains later this afternoon.

HAZARDS/WEATHER TRENDS: VFR conditions will prevail over the next 24
hours for all terminals. Windy conditions at KRWL and KLAR after 17z
today with gusts up to 35 knots. Rain shower activity and some
embedded thunder possible, but coverage of thunderstorms is
uncertain at this time. Shower and thunderstorm activity may result
in brief strong wind gusts at times, but MVFR or lower conditions
appear unlikely at this time due to high cloud bases.

&&

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

&&

$$

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