217
FXUS65 KGJT 040013
AFDGJT

Area Forecast Discussion
National Weather Service Grand Junction CO
613 PM MDT Fri Oct 3 2025

.KEY MESSAGES...

- Breezy southwesterly winds with gusts of 30-40 mph are
  occurring today and expected tomorrow.

- Showers and storms associated with the approaching low
  pressure have begun over the higher terrain today, and will
  become widespread by tomorrow morning. Light snow is possible
  above 9k feet.

- Temperatures drop below normal tomorrow and Sunday, then
  rebound to near normal values Monday as warmer and more
  seasonable conditions return.

&&

.SHORT TERM /THROUGH SATURDAY NIGHT/...
Issued at 246 PM MDT Fri Oct 3 2025

Showers and some thunderstorms have begun, primarily in the
southern half of the CWA, where moisture is beginning to advect
into the region ahead of the incoming low pressure system. Water
vapor satellite imagery shows that the low pressure system is
currently centered over California. As the low moves across the
Intermountain West overnight, bringing increasing amounts of
upper level support to the region, PoPs will increase across
most of the CWA. The moisture transport associated with this
system will elevate PWAT values to above 200% of normal in some
areas. Given the abundance of moisture and sufficient forcing,
widespread rain is expected overnight tonight and tomorrow
morning. Snow is possible above 9kft, but really only an inch or
two is expected at most. Perhaps a few very localized areas may
see a bit more. Once the system moves east of the Rockies
tomorrow night dry air moves in from the southwest. So, PoPs
will decrease from southwest to northeast through the day
Saturday as both upper level support and moisture decrease.

Gusty winds are ongoing this afternoon, partially from mixing
with stronger winds aloft, but also from strong wind gusts
associated with showers and thunderstorms. Tomorrow
synoptically driven wind gusts of up to 30 to 40 mph are
possible, potentially even greater in some areas, especially
southwest Colorado where Wind Advisories are in effect from 10
AM to 5 PM MDT tomorrow.

A cold front moves across the region during the day tomorrow,
dropping high temperatures significantly. Today high
temperatures will be about 10 degrees above normal, but highs
will drop down to around 5 degrees below normal tomorrow, a
decrease of nearly 15 degrees for many locations. Overnight low
temperatures tonight into tomorrow will be much warmer than
Saturday night into Sunday. This is a result of drier air
clearing cloud cover Saturday night for all but the northern
border of our CWA.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
Issued at 246 PM MDT Fri Oct 3 2025

The long term period will start out with a long wave trough draped
across much of the Intermountain West. The best support will remain
over Wyoming, Idaho and Montana so while there will be a slim chance
for a few isolated showers over the northern mountains, quiet
conditions will be the rule. Upper level support will then shift to
the Plains which will cause the trough to remain in place.
Eventually, a closed low will form in the base of the trough, Monday
into Tuesday. By Wednesday, the system will start tracking eastward
causing flow to become more southwesterly. While available moisture
to the south will be entrained by this flow and bring increasing
chances for precipitation, especially over the San Juans up into the
central mountains. Finally, Wednesday into Thursday the now open
wave to our west will move through the area bringing some isolated
chances for precip across the CWA. PWATs will remain at or below
normal, thus those isolated chances. High temps will be a few
degrees above normal for the most part.

&&

.AVIATION /00Z TAFS THROUGH 00Z SUNDAY/...
Issued at 557 PM MDT Fri Oct 3 2025

Isolated to scattered showers and thunderstorms are moving to
the northeast across the region. Look for these storms to
increase in coverage through the overnight becoming widespread
across the higher terrain in the region by 12Z. Gusty south to
southwest winds will increase through the evening and overnight
hours generally gusting 20-30 kts, but with convective activity,
expect gusts over 45 kts possible near passing storms. Most TAF
sites will see Low-Level Wind Shear from about 03Z through about
17Z. Mountain TAF sites will see periods below ILS breakpoints
mostly due to low ceilings with these storms. These showers and
thunderstorms will diminish southwest to northeast after 15Z
moving out of the region to the northeast by about 00Z Sunday.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

CO...Wind Advisory from 10 AM to 5 PM MDT Saturday for COZ020-021.
UT...None.

&&

$$

SHORT TERM...GF
LONG TERM...TGR
AVIATION...DB