009
FXUS65 KGJT 102125
AFDGJT

Area Forecast Discussion
National Weather Service Grand Junction CO
325 PM MDT Wed Jul 10 2024

.KEY MESSAGES...

- Temperatures will continue to climb into the weekend. Near
  record highs are expected Friday and Saturday. Heat Advisories
  remain in place for portions of eastern Utah and the Grand
  Valley.

- Afternoon showers and thunderstorms will develop over higher
  terrain each day throughout the next 7 days with an increase
  in coverage expected early next week.

- Temperatures remain elevated beyond the weekend, but some
  relief is expected from cloud cover and shower activity, as
  monsoonal moisture is forecast to return early next week.

&&

.SHORT TERM /THROUGH THURSDAY NIGHT/...
Issued at 221 PM MDT Wed Jul 10 2024

High pressure over the Great Basin and Desert Southwest showed
little indication of moving over the next 48 hours according
to model consensus. On the eastern edge of the high, mid-level
water vapor imagery indicated a stream of moisture moving
southward over the Continental Divide, which has been the case
over the past few days. Daytime heating has resulted in
scattered showers/thunderstorms over the mountains along and
west of the Divide. In the absence of dynamic lift, expect
diurnal cooling will put storms to bed early this evening with
skies clearing overnight. Given the quasi-stationary pattern,
expect the same scenario to play out on Thursday with storms
developing early in the afternoon, mainly over the mountains of
the Divide, then dying early in the evening. Lows tonight and
Thursday night will be near, or just a little above normal
while highs rise a degree or two Thursday afternoon.
Temperatures not quite at the level to warrant adding to the
Heat Advisories in effect this Friday and Saturday.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
Issued at 221 PM MDT Wed Jul 10 2024

By Friday, the high pressure will be centered over Utah slowly
tracking east to be in position over the Colorado Rockies Saturday.
A dry airmass caught up in the flow around the high moves in over
the northern areas to limit convection over the northern mountains
Friday afternoon, but moisture from the Front Range moves into the
San Juans to feed scattered showers and thunderstorms in the south
with isolated convection to the north in the central Colorado
mountains. The high tends to remain parked over the region through
Monday with a tap to deeper moisture off the Gulf of California to
move up into the Great Basin. From Monday onwards, the models
diverge on solutions as to what happens to the high with some
keeping it in place or even shifting east of the Divide while others
push it back to the west/southwest with the shortwave dropping down
over the Northern Plains. With the high wobbling over the mountains,
models sneak in some of the moisture out of the Great Basin into
eastern Utah and Western Colorado Sunday onward. Expect a slight
uptick in showers and thunderstorms spreading to the northwest to
about the I-70 corridor Sunday afternoon and becoming widely
scattered across all the higher terrain Sunday evening. They
continue to somehow increase the moisture across the region Monday
and Tuesday though the high stays mostly in place with showers and
thunderstorms becoming more widespread across the higher terrain by
Tuesday. There is little confidence in the forecast beyond Sunday,
so we`ll have to wait and see.

Under the high pressure, temperatures continue to warm going into
the weekend with Saturday being the warmest day five to ten degrees
above normal for July. Models are consistent increasing the cloud
cover with the influx of moisture to limit diurnal heating and cool
the region with increased showers resulting in evaporative cooling.
Temperatures fall a few degrees each day Sunday through Tuesday,
but again, confidence is low beyond Sunday.

&&

.AVIATION /18Z TAFS THROUGH 18Z THURSDAY/...
Issued at 1143 AM MDT Wed Jul 10 2024

Expect VFR conditions across the region outside any showers or
thunderstorms through the TAF period. Scattered cloud are
building on the terrain today, along with some scattered showers
and thunderstorms. The primary threats from these storms will
be 40-50 mph outflows winds and small hail. Included vicinity
showers and thunderstorms at the mountain terminals. Winds will
be generally light and terrain influenced outside of shower
activity. Showers will quickly diminish towards sunset.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

CO...Heat Advisory from 10 AM Friday to 9 PM MDT Saturday for
     COZ006.
UT...Heat Advisory from 10 AM Friday to 9 PM MDT Saturday for
     UTZ024-027-029.

&&

$$

SHORT TERM...NL
LONG TERM...DB
AVIATION...TGJT