Chadron, Nebraska 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

127
FXUS65 KCYS 270834
AFDCYS

Area Forecast Discussion
National Weather Service Cheyenne WY
234 AM MDT Thu Aug 27 2026

.KEY MESSAGES...

- There is a Marginal Risk (Level 1 of 5) for severe weather
  for portions of southeast Wyoming and western Nebraska on
  Thursday. Large hail and damaging wind are the primary
  hazards.

- Friday will act as a transition day between active weather to
  more organized active weather Saturday onwards.

- Daily shower and thunderstorm chances expected Saturday
  through at least Thursday, with the potential for strong
  thunderstorms Sunday afternoon.

&&

.SHORT TERM /THROUGH FRIDAY NIGHT/...
Issued at 233 AM MDT Thu Aug 27 2026

Upper-level ridging continues today as an upper-level trough starts
to dig into the Pacific Northwest. Models are starting to trend
downward in the upper-level flow across the region. However, the
500mb high remains over the Four Corners regions, funneling moisture
and 500mb vorticity maxima into the CWA throughout the day today.
The 700mb ridge remains in place across the region during the day,
but a shortwave will try to nose through Thursday night into early
Friday morning, flipping flow to the southwest rather than west to
northwest. Modest 700mb warm air advection will be present this
afternoon and into the evening hours, enabling low-level forcing for
ascent to increase this afternoon. A surface low pressure system
attempts to form around 21Z this afternoon, increasing surface
pressure gradients east of the Laramie Range. Temperatures this
afternoon will increase into the low-80s to low-90s across the
region with cloud cover increasing this afternoon. Surface dewpoints
will remain in the 50s this afternoon across western Nebraska with
much of southeast Wyoming in the 30s and 40s. The lower moisture
looks to weaken some of the instability this afternoon, with
forecast RAP and HRRR soundings suggesting only around 500 to 1000
J/kg of MLCAPE and SBCAPE. This has decreased significantly from
yesterday when forecast models were suggesting 2000 to 2500 J/kg of
MLCAPE and SBCAPE. DCAPE values have increased to around 1300 to
1600 J/kg this afternoon, suggesting an increasing threat for
downbursts across much of the region. Bulk shear values are coming
in a touch lower as well, only around 30kts rather than the 35 to
40kts modeled yesterday. Overall, the severe threat may be more
limited in spacial extent. A storm could find a pocket of higher
CAPE this afternoon, causing them to strengthen and drop some large
hail. The Storm Prediction Center keeps the region in a Marginal
Risk (Level 1 of 5) for severe weather with damaging winds and large
hail (2+ inches) as the primary hazards. Today looks more likely to
see one or two severe storms, but those storms could produce very
large hail. Precipitable Water values remain around an inch today,
so localized flooding is possible.

A brief reprieve from scattered thunderstorms is anticipated Friday
as the upper-level start to transitioning to another active pattern.
The upper-level ridge remains in place Friday, strengthening just a
touch, before starting to move off to the east and tilt towards the
northeast. The 500mb high over the Four Corners continues to spin
through the afternoon hours Friday, but gets pushed off to the south
and east and starts to become less organized Friday night into early
Saturday morning. 700mb flow turns westerly Friday with a brief
period of elevated height gradients possible between 21 and 06Z. GFS
downward omega values remain modest at best, but could be enough to
mix some of the stronger winds down towards the surface. High winds
remain unlikely at this time, but stronger flow is anticipated
across Carbon County where southwesterly surface flow develops and
surface pressure gradients increase as a high develops over western
Colorado. 700mb temperatures also increase into the 15 to 19C range
for Friday as the apex of the trough briefly moves directly
overhead. Surface temperatures look to max out in the low- to upper-
90s in all locations east of the Laramie Range. These very warm
temperatures combined with gusty downsloping winds along and east of
the Laramie Range, as well as minimal precipitation chances, will
lead to elevated fire weather conditions. Afternoon minimum humidity
values will drop into the 15 to 20 percent range across much of the
area, but Red Flag conditions are not anticipated at this time.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
Issued at 233 AM MDT Thu Aug 27 2026

The upper-level ridge gets pushed off to the east Saturday as an
upper-level trough digs into the Pacific Northwest. Strong,
southwesterly flow aloft develops as height gradients increase
between the departing ridge and the incoming trough. The 500mb high
will be pushed well off to the east over eastern Texas and Oklahoma,
but a large fetch of southwesterly flow is anticipated from the
Pacific Ocean, just off the coast of southern California, all the
way through the Northern Plains. The 250mb jet streak over western
Wyoming looks to develop around 21Z, placing much of the region
within the right entrance region of the upper-level jet, favoring
dynamically induced lift. 700mb flow will be quite elevated across
western portions of the CWA Saturday morning before weakening
through the mid-morning and early-afternoon hours. Strong 700mb WAA
will be present once more east of the Laramie Range before cooler
temperatures arrive ahead of the incoming upper-level trough.
Westerly flow is anticipated to return by Sunday morning across the
region, favoring slightly drier conditions. Another round of showers
and thunderstorms will be possible Saturday, but the best lift
arrives on Sunday with the upper-level trough. Forecast sounding
from the RAP suggest a stout Inverted-V signature across much of the
region, with around 1000 to 1500 J/kg of DCAPE. Therefore, showers
and storms on Saturday may be quite gusty with increasing potential
for microbursts. Temperatures Saturday will be warm again, in the
low-80s to upper-90s across the region. Hottest conditions are
anticipated in western Nebraska, where some locations could be
pushing 100F.

Sunday onwards looks to remain quite active across the region as
upper-level flow become more influenced by the incoming trough.
Sunday may be particularly interesting day, weather wise, as the
upper-level trough deepens and takes on a more negative tilt as it
digs into northern portions of the Intermountain West. Strong 500mb
vorticity maxima look to eject across the region, though 700mb WAA
remains very low across the region. Dewpoints remain in the 40s and
50s, so another active day looks possible Sunday, especially with
the enhanced dynamics from the strong upper-level trough. Once the
trough moves through, an open wave develops with southwesterly flow
continuing across the CWA. Multiple shortwaves look to push through
the flow, so daily precipitation chances are expected to continue
through much of the week. Temperatures look to remain seasonable to
slightly warm across the CWA.

&&

.AVIATION /06Z TAFS THROUGH 06Z FRIDAY/...
Issued at 1133 PM MDT Wed Aug 26 2026

VFR conditions will prevail across all terminals for the duration of
this TAF period. Winds will pose no aviation concern as they
become/remain variable to generally less than 6 knots for all sites
through the overnight hours. There will be a slight uptick in winds
by 00Z Friday, but even though winds should remain less than 15
knots.

&&

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

&&

$$

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