Area Forecast Discussion
Issued by NWS Grand Junction, CO

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598
FXUS65 KGJT 232326
AFDGJT

Area Forecast Discussion
National Weather Service Grand Junction CO
526 PM MDT Mon Sep 23 2024

.KEY MESSAGES...

- Isolated storms may linger over southwest Colorado through
  sunset otherwise dry conditions are expected.

- Dry and warm conditions are expected during the remainder of
  the week as high pressure settles over the region. Near record
  highs are expected from Thursday through the weekend.

&&

.SHORT TERM /THROUGH TUESDAY NIGHT/...
Issued at 256 PM MDT Mon Sep 23 2024

Weak troughing aloft will be transitioning to an expansive and
strong ridge over the next 24 hours or so. There is some last
gasp convection forming over the southern terrain this afternoon
as a result...but after this a prolonged dry and warm period
will be setting up. Perfect fall weather...though it will still
feel like summer as temperatures warm well above normal. Highs
tomorrow look to start out 2 to 5 degrees above climatology
then pushing 10 to 15 above by the end of the week. Overnight
lows will continue to be cool in this dry pattern. With
lingering low level moisture isolated areas of morning fog
popped up in some of the valleys this morning. With a drying
profile this should become less likely but this remains a low
confidence forecast.

&&

.LONG TERM /WEDNESDAY THROUGH MONDAY/...
Issued at 256 PM MDT Mon Sep 23 2024

An omega "blockish" pattern sets up by Wednesday with low pressure
off the SoCal Coast and in the Mississippi Valley with ridging along
the Rocky Mountains. It`s only "blockish" in that the western half
of the pattern lacks jet support with the jet remaining well to the
north in a zonal flow that keeps the ridging knocked down,
especially later in the period when the ridging limited to Colorado
and New Mexico. Being in the shoulder season, leaning on the
ensemble mean forecasts in the long term gives similar solutions
through the extended forecast period. That being said, confidence
falls somewhat beyond Friday or Saturday with the deterministic GFS
and some ensemble members digging a deep trough into the Pacific
Northwest by Sunday bringing unsettled weather to the region. Though
this is a minority solution, it is feasible with lack of jet support
to the west. We`ll just have to wait and see how this plays out.

That being said, the extended forecast through next Monday for
eastern Utah and Western Colorado is for dry conditions under mostly
sunny skies and generally light, terrain driven breezes.
Temperatures will run eight to 13 degrees above the seasonal normal
temperatures for early Fall through the period with the lower
valleys on the higher end and the mountains on the lower end.

&&

.AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/...
Issued at 522 PM MDT Mon Sep 23 2024

A few, very isolated showers and a quick storm or two have
popped over the San Juans this afternoon but they won`t affect
any TAF sites. The remainder of the evening will see the cumulus
clouds over the higher terrain dissipating while high clouds
continue to stream overhead. VFR conditions will remain in place
with light winds expected. Did not put any fog in for KGUC in
the morning but this possibility will need to be watched.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

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

&&

$$

SHORT TERM...15
LONG TERM...DB
AVIATION...TGJT