-- Discussion containing changed information from previous version are highlighted. --
818
FXUS65 KGJT 191109
AFDGJT

Area Forecast Discussion
National Weather Service Grand Junction CO
509 AM MDT Thu Sep 19 2024

.KEY MESSAGES...

- Conditions will remain dry with near average temperatures today
  and tomorrow.

- The next system arrives on Saturday bringing scattered showers
  and a reinforcing shot of cooler air.

- The central mountains look to be favored for a majority of the
  precipitation with some in the form of snow.

&&

.SHORT TERM /THROUGH FRIDAY/...
Issued at 145 AM MDT Thu Sep 19 2024

A closed low pressure is currently tracking southward along the
coast of California causing southwest flow aloft over our
region. This will allow temperatures to warm up slightly closer
to normal. High clouds work in later today across the southern
half of the area. Tomorrow the low pressure moves inland over
the Desert Southwest keeping us in southwest flow. It will begin
to tap into some moisture in New Mexico and result more clouds
over the southern and central mountains later in the day.
Conditions will remain dry and temperatures warm a few degrees.

&&

.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
Issued at 145 AM MDT Thu Sep 19 2024

By Friday night the system will have made it to the lowest
latitude it is going to and begin to lift back northward toward
the 4 Corners by sunrise on Saturday. The models have come into
better alignment as expected in the middle part of the forecast
period through Sunday evening as this system crosses our CWA and
moves into High Plains. The moisture advection remains modest
with PWAT showing no excessive anomaly as this system works
through. This storm will be wrapped up enough that the warm
conveyor belt will pull Gulf of Mex moisture back westward
toward northeast CWA early Sunday before the drier northwesterly
flow sets up later in the day. The prolonged tap of moisture
and fairly robust large scale ascent accentuated by the
cyclonically curved jet max rounding the base of the system
Saturday night signals a wet forecast over our eastern CWA but
especially the central mountains. Now...time of year comes into
play...but the snow levels look to lower near pass level and we
could see some wet snow falling over the higher passes by
sunrise on Sunday. Confidence is extremely low there will be any
impacts with warm road conditions and the wet nature of the
snow but the peaks above timberline are likely to get a fresh
coat of white before this is over later on Sunday. As previously
mentioned downstream blocking in the pattern remains a factor
and the models are now merging toward consensus in digging the
next high latitude energy down the lee of the Rockies on Monday
leaving deep northerly flow in place into Tuesday. This trough
is coming through with minimal moisture and even the overly
excessive blended model PoPs remain on the lower side early next
week. Midweek and beyond is a coin toss as the EURO closes a
low over the Southern Plains while the latest GFS builds a large
in across much of the West into High Plains. Temperatures will
be coolest over the weekend under the passing system then look
to gradually warm beyond this...unless the EURO wins the coin
toss.

&&

.AVIATION /12Z TAFS THROUGH 12Z FRIDAY/...
-- Changed Discussion --
Issued at 509 AM MDT Thu Sep 19 2024

VFR conditions and light terrain-driven winds are expected
through the taf period.
-- End Changed Discussion --

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

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

&&

$$

SHORT TERM...KJS
LONG TERM...15
AVIATION...TGJT