737
FXUS65 KCYS 072052
AFDCYS

Area Forecast Discussion
National Weather Service Cheyenne WY
252 PM MDT Fri Aug 7 2026

.KEY MESSAGES...

- Red Flag Warning continues for parts of southeast Wyoming west
  of I-25 until 8 PM this evening.

- Another Red Flag Warning is in effect from 11 AM to 8 PM
  Saturday for all of southeast Wyoming for very low humidities
  and significant gusty winds.

- Hot temperatures will continue through Monday before the heat
  is lessened for Tuesday onward with isolated to scattered
  showers and thunderstorms expected for Tuesday through next
  Friday.

&&

.SHORT TERM /THROUGH SATURDAY NIGHT/...
Issued at 250 PM MDT Fri Aug 7 2026

Tonight... Thank you very much to our neighboring NWS office
team at Riverton, Wyoming for providing service backup today to
our NWS Cheyenne team. Inherited Red Flag Warning is in decent
shape looking at bone dry relative humidities and expected winds
currently through this evening. Thus will continue the Red Flag
Warning for our fire weather zones across much of Carbon and
portions of Albany Counties until 8 PM. Another quiet and
comfortable overnight with excellent radiational cooling due to
low dewpoints. Boundary layer winds and humidities suggest
scattered to widespread low clouds developing across the
Nebraska Panhandle after midnight and until early morning after
daybreak, with a decent low level jet also bumping up the winds,
especially at typically windy Chadron and Alliance under low
level jet conditions.

Saturday...Main challenge will be Fire Weather concerns.
Northwest flow aloft continues and with a decent bump in the mid
level winds around 700 mb, near 10,000 feet MSL, looking at
decent mix down winds exceeding Red Flag Warning criteria for
all of southeast Wyoming looking at NAM MET and MAV data,
especially with a decent 700 mb jet moving overhead in the
afternoon. Minimum humidities will definitely be low enough for
criteria, and thus we will issue another Red Flag Warning for
all of our southeast Wyoming fire weather zones. Winds across
the Nebraska Panhandle will be lighter and thus we will hold off
on a Red Flag Warning there. Soaring temperatures once again
based on projected 700 mb temperatures, full sun and downslope
warming projecting maximum temperatures from 90 to 102 degrees.
Fortunately, apparent temperatures and heat index values will be
reasonable due to low relative humidities.

Saturday night... Minimum temperatures will be moderated again
by the above normal airmass, though still quite comfortable for
sleeping with the windows open due to excellent radiational
cooling. Continued dry with scarcity of available moisture.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
Issued at 250 PM MDT Fri Aug 7 2026

A suppressed ridge pattern will continue throughout the majority
of the long-term forecast period. Monsoonal ridging throughout
the weekend will gradually subside, with the 500mb jet generally
positioned from the Washington/Oregon cascades and stretching
across the northern Rockies into the high plains of Montana and
northern Wyoming. South of this feature, gradually deepening
moisture will spread across the central and southern Rockies
from the Four Corners eastward through the high plains. PWAT
values at selected sites across southeast Wyoming and western
Nebraska all show a steady rise each day from Sunday through the
end of the week. This will lead to increasing coverage of
showers and thunderstorms each day. By the Wednesday-Friday
timeframe PWAT normalized anomalies in ensemble guidance will
run around 2 to 2.5 standard deviations above the mean. This
will result in high confidence of afternoon thunderstorms, some
of which may contain heavy drenching downpours. Despite better
thunderstorm chances, severe weather remains generally unlikely
in southeast Wyoming with mostly light westerly flow in the mid
and upper-levels present. Farther east into the Nebraska
Panhandle, some faster flow aloft will begin to impinge on the
area from the north by Wednesday as the aforementioned ridge of
high pressure continues to become more suppressed to the south.
Low-end wind shear values on the order of 30-40 knots may assist
with multicell storm modes that could produce organized outflow
wind events during the afternoon hours from Wednesday through
Friday. High confidence exists in above-normal temperatures
continuing through the entire long-term period. However,
increasing coverage of afternoon thunderstorms from mid-week
onward will likely limit temperatures somewhat, generally
running around 10 degrees above normal instead of the near-
record daily heat we will experience this weekend. Overall,
generally high confidence exists in the long-term period with
excellent agreement in ensemble guidance with regard to synoptic
forecast features.

&&

.AVIATION /18Z TAFS THROUGH 18Z SATURDAY/...
Issued at 1121 AM MDT Fri Aug 7 2026

VFR conditions continue through the next 24 hours with minimal
to no cloud cover expected. Winds have been increasing this
morning, and gusts of 20 to 25kts are expected at all sites
through this evening. Wind gusts will relax after sunset for
Wyoming sites, but gusts 15 to 20kts will continue across
Nebraska through most of the overnight hours. Smoke will also be
notable into Saturday. Visibilities should remain above 6sm, but
some glide path visibility may be reduced briefly around sunset
tonight.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...Air Quality Alert until noon MDT Monday for WYZ101>119.
     Red Flag Warning from 11 AM Saturday to 9 PM MDT Sunday for
     WYZ417>433.
     Red Flag Warning until 8 PM MDT this evening for WYZ420>422-
     425>427.
NE...None.

&&

$$

SHORT TERM...RUBIN
LONG TERM...MAC
AVIATION...WFO-RIW