331
FXUS65 KGJT 020526
AFDGJT

Area Forecast Discussion
National Weather Service Grand Junction CO
1126 PM MDT Fri Aug 1 2025

.KEY MESSAGES...

- Showers and thunderstorms continue over the high terrain today
  with the potential for gusty outflow winds up to 50 mph.

- Red Flag Warnings are in place for portions of eastern Utah
  and western Colorado tomorrow afternoon as widespread
  critical fire weather conditions are expected.

- Smoke and haze from regional wildfires will remain visible
  through the period.

&&

.UPDATE...
Issued at 803 PM MDT Fri Aug 1 2025

Updated to let the Red Flag Warning expire at 7 pm MDT for NW
Colorado Fire Zones as winds have dropped below critical
thresholds and relative humidity has increased. Red Flag Warning
conditions become more widespread on Saturday and appear on
track.

&&

.SHORT TERM /THROUGH SATURDAY/...
Issued at 316 PM MDT Fri Aug 1 2025

Dry air is beginning to slot into eastern Utah and western
Colorado behind a handful of active thunderstorms. We`ve seen
storms produce pea- to nickel-sized hail today, which may
continue throughout the mid-afternoon. This is mostly owed to a
moderately sized pocket of 35-45 kt shear centered near the
Gunnison Basin. Cells near and north of I-70 aren`t receiving as
strong of shear though and will likely be more prone to
stronger outflow gusts (35+ mph) than hail. With minimal
additional storm development in the encroaching drier
environment, the more potent storms are expected to come to an
end earlier in the day than seen over the past couple days.
CAM`s are hinting that convection will become weak and isolated
between 5 and 8 PM with a mostly quiet night ahead.

Showers and thunderstorms are still expected tomorrow, albeit
they should remain mostly anchored to the high terrain. We will
instead be shifting our concern more towards critical fire
weather conditions as sub-15% relative humidities will fill into
most areas along the Colorado-Utah border. Winds pick up too
with gusts exceeding critical fire weather criteria and localized
pockets of 30-35 mph gusts possible as well. Red Flag Warnings
have been issued for these areas from 1 to 7 PM tomorrow as a
result.

&&

.LONG TERM /SATURDAY NIGHT THROUGH FRIDAY/...
Issued at 350 AM MDT Fri Aug 1 2025

A broad area of high pressure will remain centered over southern
Arizona and New Mexico at the start of the long term period. A few
lingering showers may persist along the Divide Saturday night
because of the previous wave that moved through the region. Starting
Sunday and persisting through Tuesday, hot, dry, and windy
conditions will set up across the region. Speaking of, the hot, dry,
and windy index is showing values above the 95th percentile through
the same time period. PWATs will be well below normal while daytime
RH values will dip into the single digits. Thus, all of the
ingredients will be in place for critical fire weather conditions
for the upcoming days though location and coverage will differ day
by day. Looking ahead to Wednesday and Thursday, some ensembles are
indicating a quick surge in moisture as the high drifts to the east.
A wave may work on this moisture bringing a return to some showers
and thunderstorms. The GFS ensembles are more aggressive with this
scenario versus the EC ensembles though the EC also brings in this
precip. Plenty of time to work out the details. As one would expect,
temperatures will be running hot through the period...5 to 10
degrees above normal.

&&

.AVIATION /06Z TAFS THROUGH 06Z SUNDAY/...
Issued at 1118 PM MDT Fri Aug 1 2025

Drier conditions return tomorrow but residual moisture will
allow a few showers and storms to fire over the higher terrain.
KEGE and KASE may see some convection so included PROB30 groups
for those sites. KGUC and KHDN may also see some convection but
confidence not high enough to include now. Remaining TAF sites
are expected to remain dry. Gusty winds of 20 to 30kts will
also materialize in the afternoon affecting TAF sites. VFR
conditions will continue for the next 24 hours.

&&

.FIRE WEATHER...
Issued at 803 PM MDT Fri Aug 1 2025

Critical fire weather conditions are expected for the next
several days amid a drying pattern. Critical fire weather
conditions become more widespread tomorrow as humidities drop
and gusts increase to over 30 mph in some locations. Thus, most
zones along the CO-UT border have been placed in Red Flag
Warnings tomorrow. Scattered showers are anticipated again
tomorrow, which could bring wetting rain to some ongoing fires,
though frequent lightning will pose a threat of new ignitions.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

CO...Red Flag Warning from 1 PM to 7 PM MDT Saturday for COZ200-202-
     203-207-290.
UT...Red Flag Warning from 1 PM to 7 PM MDT Saturday for UTZ487-490-
     491.

&&

$$

UPDATE...MDA
SHORT TERM...BW
LONG TERM...TGR
AVIATION...TGJT
FIRE WEATHER...TGJT