962
FXUS65 KGJT 230000
AFDGJT

Area Forecast Discussion
National Weather Service Grand Junction CO
600 PM MDT Fri Aug 22 2025

.KEY MESSAGES...

- Unseasonably warm temperatures continue through tomorrow,
  before increased clouds and showers bring a significant cool-
  down for early next week.

- Scattered to widespread convection develops over the higher
  terrain tomorrow with gusty winds and lightning still the main
  threats. Moderate rainfall will be possible over the San
  Juans.

- Moisture continues to increase over the next several days,
  with widespread shower and storm activity expected. Potential
  for heavy rain and debris flows over burn scars will be
  heightened from Sunday into early next week.

&&

.SHORT TERM /THROUGH SATURDAY NIGHT/...
Issued at 258 PM MDT Fri Aug 22 2025

The 18z KGJT radiosonde flight showed that PWATs have increased
to 0.88" as moisture continues to drop south across western
Colorado and eastern Utah this afternoon. Scattered convection
will continue into the evening, mainly across the high terrain
but a few showers and storms may move off the terrain and into
adjacent valleys. Gusty outflow winds up to 35 mph and frequent
lightning are the main threats of storms today. There`s not much
CAPE for storms to work with, so strong storms are not
anticipated.

Similar conditions develop again tomorrow with scattered
afternoon convection over the higher terrain. Drier air moves
back in over the northern third of our forecast area (north of
the I-70 corridor) so precipitation chances are highest along
and south of I-70. Wetting rain chances continue to increase,
but isolated dry thunderstorms cannot be ruled out with drier
air in place across northwest Colorado.

Temperatures remain unseasonably warm for one more day, but
will be a few degrees cooler than the record-setting heat we`ve
experienced the past few days.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
Issued at 258 PM MDT Fri Aug 22 2025

The wet pattern is expected to persist well into next week with
most of the week on track to produce widespread precipitation
and QPF up to 0.45 inches. This is owed mostly to the high
pressure centered near the Four Corners beginning to move
eastwards again, pulling the plume of anomalous moisture over
the western CONUS back over our CWA. PWAT anomalies upwards of
175% of normal are thus likely over portions of the region
through Wednesday. It may be a little too early to begin
expecting relief for our extreme drought conditions though as it
remains to be seen how this precipitation may present itself,
be it through a stratiform or convective storm mode. And it is
entirely possible that the storm mode will vary heavily from
day- to-day. Lingering morning cloud cover will play the largest
role in determining daily storm mode. Should cloud cover
struggle to clear past sunrise, lacking surface heating may
result in steadier and more widespread stratiform rain, which
would provide us more in the way of potential drought relief
than a more convective setup. What complicates the setup though
are various shortwaves which will travel through the overhead
ridge. Stronger dynamics during these periods may yield an
environment more favorable for stronger convective storms, which
would limit the overall coverage, yet produce heavier rainfall
in localized areas. With higher resolution guidance from CAM`s
still unavailable, it is still too difficult to determine the
details of this active period. While rain in any capacity would
be a welcome relief for our drought concerns, it is also
important to note that flash flooding should still be considered
a notable risk throughout this wet pattern, particularly over
burn scars, regardless of storm mode.

&&

.AVIATION /00Z TAFS THROUGH 00Z SUNDAY/...
Issued at 557 PM MDT Fri Aug 22 2025

Shower and thunderstorm activity will continue to impact several
TAF sites with either gusty outflow winds or lightning and
precipitation near the airfield through the late evening hours.
Smoke from nearby wildfires could also impact operations at KEGE
and KASE but for now observations show the visibility is
unlimited. Expect another round of storms and similar impacts
tomorrow afternoon.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

CO...None.
UT...None.

&&

$$

SHORT TERM...KAA
LONG TERM...BW
AVIATION...TGJT