752
FXUS65 KGJT 060220
AFDGJT

Area Forecast Discussion
National Weather Service Grand Junction CO
820 PM MDT Tue Aug 5 2025

.KEY MESSAGES...

- Widespread critical fire weather conditions will continue
  Wednesday, Thursday and Friday with Red Flag Warnings in
  place.

- High temperatures will remain above normal through the week.

- There is a slight chance for dry thunderstorms tomorrow,
  exacerbating the threat of new fire starts.

&&

.UPDATE...
Issued at 820 PM MDT Tue Aug 5 2025

Even though relative humidities are slow to recover and still
remain below critical fire weather thresholds of 15 percent,
winds have decreased below critical fire weather thresholds.
Therefore, as critical fire weather conditions appear more
localized, updated to let the current Red Flag Warning today
expire at 8 pm MDT this evening. Red Flag Warnings remain in
effect Wednesday, Thursday and Friday.

&&

.SHORT TERM /THROUGH WEDNESDAY NIGHT/...
Issued at 239 PM MDT Tue Aug 5 2025

High pressure located to our southeast is keeping us warmer than
normal and that along with dry air has resulted in critical fire
weather for a good portion of the area. Wind gusts of 20-40 mph will
be common with relative humidity in the teens and single digits each
afternoon. A stream of moisture moves in from the southwest
overnight and tomorrow, coupled with the entrance region of a jet.
This moisture and jet may be enough for high based showers and
storms south of I-70 and focused on the higher terrain. These
showers will produce more lighting and wind than rainfall, which is
a concern for new wildfire starts. Humidity goes up a couple of
degrees across the southeast, where the moisture is, therefore held
off on issuing a red flag for those locations.

&&

.LONG TERM /THURSDAY THROUGH TUESDAY/...
Issued at 239 PM MDT Tue Aug 5 2025

High pressure continues to bake the Southwest Thursday. A strong
pressure gradient remains in place along the northwest quadrant of
this high thanks to low pressure working into the PACNW Thursday
afternoon. These strong winds aloft will, once again, mix down to
the surface across eastern Utah and western Colorado, producing
critical fire weather conditions around the region. Low relative
humidities and wind gusts 30 to 40 mph are expected Thursday and
Friday. Red Flag Warnings are in place both days. Temperatures
will remain well above average around the CWA into Saturday due
to strong southwesterly flow and the subsident air mass above
us. The passing low to our north is expected to drive height
falls and provide some relief to temperatures and winds Saturday
and Sunday. Little relief in relative humidities will likely
keep some level of critical fire weather in place over the
weekend. Models are hinting at some monsoonal flow returning
into the Four Corners late Saturday night, but confidence
remains low in this solution as models are coalescing around
ambivalent flow patterns across the southern CONUS with a
progressive wavy pattern for the northern tier of the CONUS.
This puts us in a potential conundrum with a dry boundary layer
and weak shower development unable to provide any wetting rains.
Gusty outflows and dry lightning on wildfires remain a concern.
Numerical temperature guidance suggests a cooling on Sunday,
Monday, and Tuesday thanks to cloud cover and potential
northwesterly flow moderating the hot and dry air mass. Again,
these are low confidence solutions given the early nature of
this regime change and inconsistent model output. Persistence
has also shown little in the way of meaningful monsoon flow each
time the high has shifted this season.

&&

.AVIATION /00Z TAFS THROUGH 00Z THURSDAY/...
Issued at 557 PM MDT Tue Aug 5 2025

Winds will continue to gust 25 to 35 mph at times this evening
with terrain driven winds, breezy at times, overnight. SCT to
BKN mid and high clouds will continue streaming over the area
with areas of smoke from surrounding wildfires. Some isolated
dry thunderstorms are possible over the high terrain Wednesday
afternoon but are not expected to impact TAF sites with another
afternoon of gusts to 35 mph. VFR conditions remain in place.

&&

.FIRE WEATHER...
Issued at 239 PM MDT Tue Aug 5 2025

Dry and windy conditions are forecast through the upcoming week. The
monsoon is effectively cut off and thus the chance of wetting
rainfall will be minimal to zero over most areas. Pockets of
elevated moisture work through with some storms possible over the
higher southern and central mountains. In lower elevations gusty
outflow winds and new fire starts from lightning are a big
concern.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

CO...Red Flag Warning from 11 AM to 8 PM MDT Wednesday for
     COZ200>203-290.
     Red Flag Warning from 11 AM to 8 PM MDT Thursday for
     COZ200>203-205-207-290-292>294.
     Red Flag Warning from 11 AM to 8 PM MDT Friday for COZ200>203-
     205-207-290-292>294.
UT...Red Flag Warning from 11 AM to 8 PM MDT Wednesday for
     UTZ485>487-490.
     Red Flag Warning from 11 AM to 8 PM MDT Thursday for
     UTZ485>487-490-491.
     Red Flag Warning from 11 AM to 8 PM MDT Friday for UTZ485>487-
     490-491.

&&

$$

UPDATE...MDA
SHORT TERM...KJS
LONG TERM...LTB
AVIATION...TGJT
FIRE WEATHER...KJS