447
FXUS65 KCYS 252338
AFDCYS

Area Forecast Discussion
National Weather Service Cheyenne WY
538 PM MDT Fri Jul 25 2025

.KEY MESSAGES...

- Warm and dry weather each day through the weekend.

- Critical fire weather conditions in southeast Wyoming possible
  on both Saturday and Sunday.

- Weak storm chances return by the middle of next week.

&&

.SHORT TERM /THROUGH SUNDAY/...
Issued at 1255 PM MDT Fri Jul 25 2025

A diffuse ridge of high pressure continues to build over the
central and southern Rockies this Friday afternoon. This
advancing ridge has shunted surface and mid-level moisture
farther east into the high plains, reducing PWAT values over
both southeast Wyoming and western Nebraska today. While surface
dewpoints in the low-50s still remain in far southeast Wyoming
and near 60 dewpoints in southwest Nebraska, forecast soundings
indicate a significantly drier moisture profile today. Thus, any
convection that does manage to develop should be extremely high
based, and limited to only areas in eastern Laramie County
Wyoming and the far southwest Nebraska Panhandle today. A gusty
shower and perhaps a rumble of thunder can not be completely
ruled out as around 20% of HREF ensemble guidance members do
fire off a few high-based storms. Expect high temperatures
overall to run around 5 degrees warmer than Thursday with a bit
more clearing expected overnight.

The diffuse ridge of high pressure will move east into the high
plains on Saturday as a weak wave passes through the Great Basin
and Front Range. This wave of energy will bring an increase to
mid-level winds, however moisture profiles will not improve
much. Thus, the expectation is for another warm and dry day on
Saturday, with increased downslope flow offsetting slightly
lower heights aloft as our wave of energy moves through. With
deep mixing expected, increased flow will likely make it to the
surface especially over Carbon and Albany counties in southeast
Wyoming. RH below 15% combined with surface gusts expected to
exceed 25 mph has resulted in the issuance of a Fire Weather
Watch. A Red Flag Warning will likely be needed if the forecast
remains on track. Expect afternoon high temperatures to increase
again by around 3-6 degrees on Saturday compared to Friday. High
temperatures in the mid to upper-90s are likely for much of the
Nebraska panhandle with Chadron likely rising over the 100
degree mark. Low to mid-90s are likely for southeast Wyoming as
well, with only a very limited shower threat along the Cheyenne
Ridge during the afternoon hours. Forecast confidence remains
very high in the short-term with only minor adjustments made to
PoP and QPF grids in this forecast package.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
Issued at 1255 PM MDT Fri Jul 25 2025

An upper level ridge will pull in warm but dry air
into the Intermountain west Sunday to keep us dry but brings along
some Fire weather concerns. NAEFS has PWAT values in the 10th and
lower percentile for SUnday and Monday to reinforce the fire
weather concerns. Winds look also to be a little breezy to put some
areas into the critical fire weather category so a Red flag may be
warranted especially for area west of the Laramie range. While the
RH values look to be under 15 percent across the forecast area the
fuels may not be cured enough to warrant a red flag warning.
Tuesday, a cold front looks to push through and provide us with our
next precipitation chances in the long term. Looking at the 700mb RH
field there looks to be a little bit of moisture associated with
this front to be utilized in afternoon convection. Wednesday, an
upper level trough moves across the Canadian Providences flattening
our upper level ridge even more than Tuesday. The synoptic ascent
combined with the continued moisture advection should continue our
precipitation chances into Wednesday night. This should also result
in cooler temperatures for the rest of the week.

&&

.AVIATION /00Z TAFS THROUGH 00Z SUNDAY/...
Issued at 538 PM MDT Fri Jul 25 2025

Storms are slowly dissipating for our Wyoming terminals but VFR
conditions should remain throughout this evening and tomorrow
morning. Tomorrow afternoon does have an isolated chance for
thunderstorms but mainly affecting KCYS and KCDR.

&&

.CYS WATCHES/WARNINGS/ADVISORIES...
WY...Fire Weather Watch from Saturday afternoon through Saturday
     evening for WYZ421>423.
NE...None.

&&

$$

SHORT TERM...MAC
LONG TERM...MM
AVIATION...MM