941
FXUS65 KCYS 052342
AFDCYS

Area Forecast Discussion
National Weather Service Cheyenne WY
542 PM MDT Fri Jun 5 2026

.KEY MESSAGES...

- Near record high temperatures and elevated to critical fire
  weather conditions are anticipated this weekend.

- Expect a quick cool down on Monday before heat builds back into
  the area towards the middle of next week.

- There is potential for widespread critical fire weather conditions
  on Tuesday and Wednesday.

&&

.SHORT TERM /THROUGH SUNDAY NIGHT/...
Issued at 216 PM MDT Fri Jun 5 2026

Currently a beautiful afternoon across the forecast area after
multiple days of severe weather. Visible satellite imagery shows a
mostly sunny day with some fair weather cumulus along and and east
of the Laramie Range. Precipitation is not expected today as dry air
settles into the region. Temperatures range from the 70s to the 80s
and will continue to get warmer as the afternoon progresses.
Although it is a bit on the warmer side, a light breeze will help
keep the air from feeling stagnant. Quiet conditions will continue
into the overnight hours with mild low temperatures expected.

Upper-level ridging will begin to amplify over the center of the
country on Saturday, placing the CWA in southwest flow aloft.
Southwest flow will usher in hot and dry desert air, leading to near-
record high temperatures over the weekend. 700 mb temperatures will
climb to +16C, which is around the 97.5th percentile for NAEFS
climatology. The anomalously warm temperatures aloft will lead
to surface temperatures potentially reaching the triple digits
on both Saturday and Sunday. Hottest temperatures are expected
in the Nebraska panhandle and the North Platte River Valley.
Cheyenne and areas west of the Laramie Range can expect
temperatures in the upper 80s. On top of the heat, it will be
very dry with mid-level relative humidity around 25 to 35
percent. Surface relative humidity will be even lower, with some
locations falling into the single digits. Windy conditions at
the surface Saturday and Sunday will add to the dryness. The CWA
will sit at the eastern periphery of a 250 mb jet, leading to
wind gusts of 30 to 40 MPH each afternoon. All these conditions
will combine to create critical fire weather conditions. A Fire
Weather Watch is in effect Saturday for the Nebraska panhandle
and far southeast Wyoming where fuels are deemed critical. Fuels
across the rest of southeast Wyoming are still in green-up and
thus not ready to burn. Despite this, critical fire weather
conditions are still forecast for the weekend.

Saturday will also feature a weak disturbance aloft that moves
across the Rockies. Even though the low and mid-level will be
extremely dry, this disturbance will spark some convective
development across the area. At this point, the HRRR shows
nothing more than some gusty showers across the area. With model
soundings showing over 1500 J/kg of DCAPE, severe winds gusts
are possible in these showers. Soundings also show a lot of
elevated convection across the Nebraska panhandle during the
afternoon on Saturday. This could lead to a few isolated
thunderstorms. These thunderstorms could produce dry lightning
across the area given how dry the lower part of the atmosphere
is. The area will once again face potential storm chances on
Sunday. A trough that will pass the CWA to the north will send a
cold front through the area Sunday evening. Some models hint
that the eastern portion of the CWA could see some
precipitation from this, albeit not that much. There are a few
CAMs that hint at thunderstorms developing in the panhandle with
1500 J/kg of CAPE, while soundings from the GFS around the same
time are less than impressive, not even hinting at any
convective potential. Regardless, there is still time to iron
out the Sunday afternoon and evening forecast as Hi-Res guidance
has the chance to catch on to this system.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
Issued at 216 PM MDT Fri Jun 5 2026

A brief reprieve from the summertime heat is on order Monday as a
strong shortwave brushes and a surface cool front drags through the
forecast area. Temperatures will remain seasonable to warm however,
with most locations east of I-25 still reaching the lower to mid
80s. Despite the increased forcing with the wave and front, moisture
will be hard to come by. Can`t rule out a few pop-up storms, mainly
near the ranges and in the panhandle, but most spots will stay dry.
The large upper ridge centered over the Great Lakes reamplifies
heading into midweek, setting the stage for another round of near
record heat for eastern Wyo and western Neb on Tuesday. The middle
of the NBM envelope suggests highs around 90F at CYS and upper 90s
for BFF/CDR. The next upper low spins into the northern Rockies
Wednesday and beyond, switching southwesterly flow aloft to
northwesterly. Temperatures should gradually back off to more
seasonable levels by late next week. In the meantime, fire weather
conditions will definitely need to be monitored. The pattern is the
epitome of "dry heat" as humidity levels drop into the lower teens
Tue-Thu. Coupled with rounds of gustier winds (30+ kts), limited
precipitation potential, and continued D2-D4 drought across the
region, additional Red Flag conditions may be realized. The
strongest winds appear to be Wednesday with a tight surface pressure
gradient in place, and Thursday as the core of the upper jet lines
up with the forecast area.

&&

.AVIATION /00Z TAFS THROUGH 00Z SUNDAY/...
Issued at 524 PM MDT Fri Jun 5 2026

Mostly clear skies over most terminals this evening, with
scattered cumulus at 10 to 8 kft lingering near the Nebraska
Panhandle terminals. Overnight a low level jet develops over the
high plains bringing in a shallow moisture rich airmass and
gusty southeastern winds. Wind gusts to 30 knots are possible.
As this jet subsides, some low lying terminals in the Panhandle
may cool enough for fog. The greatest likelihood of this
occurring is at KSNY, however coverage may extend to KBFF and
KAIA. Otherwise, ceilings to 1000 feet or below are possible
which may send terminals in the Panhandle to IFR or LIFR. Most
of the fog and low stratus deck lifts and burns off by 15z
giving way to mostly clear skies.

During the afternoon elevated convection is anticipated to
develop. Dry microburst and erratic winds are possible at all
terminals. Winds to 45 kts or greater are a slight possibility,
however given the very scattered nature of this activity, only
vicinity showers were included in some terminal TAFs. Lightning
risk seems low but not zero. A more substantial isolated
thunderstorm or two may develop in the Nebraska Panhandle at the
end of the forecast period, but again probabilities are too low
to include in this forecast.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...Fire Weather Watch from Saturday afternoon through Saturday
     evening for WYZ430>433.
NE...Fire Weather Watch from Saturday afternoon through Saturday
     evening for NEZ434>437.

&&

$$

SHORT TERM...SF
LONG TERM...DS
AVIATION...RV