878
FXUS65 KGJT 130600
AFDGJT

Area Forecast Discussion
National Weather Service Grand Junction CO
1200 AM MDT Mon Oct 13 2025

.KEY MESSAGES...

- Another round of highly anomalous moisture from TD Raymond
  moves up from the south Monday into Tuesday.

- A Flood Watch remains in effect for the southern San Juans and
  adjacent valleys. Total rainfall amounts in that area are 1-2
  inches with locally higher amounts upwards of 3-4 inches
  possible.

- Unsettled weather continues for much of the week as another
  system moves in from the west bringing more showers and storms
  to eastern Utah and western Colorado.

&&

.SHORT TERM /THROUGH MONDAY NIGHT/...
Issued at 303 PM MDT Sun Oct 12 2025

The cold front has exited the region allowing for drier air to
filter in from the west. As a result temperatures are expected to
run cooler today compared to yesterday. This break from precip will
be shorted lived as another low pressure drops southward along the
West Coast causing flow to shift back to the south. The moisture
that was pushed south by the cold front will advect back northward
as a result of the flow shift. This moisture has roots back to
tropical storm Raymond, so PWAT values are over 200% of normal once
again. Values approaching 350% of normal will filter into the
southern San Juans starting late tonight and continuing through
Tuesday, and possibly Wednesday. This is where a Flood Watch is in
effect until noon Tuesday. Tomorrow morning expect showers and
storms to move in from the south spreading to the northern CWA by
the afternoon. Moderate to heavy rainfall rates are possible, so any
locations that received several inches of rain from this last event
could experience localized flash flooding. Tomorrow night the main
low continues tracking over the West Coast keeping the southwest
moist flow in our region so training and multiple rounds of showers
is expected into Tuesday morning. Snow levels for this event are
expected to start around 10-13 kft so there could be minor
accumulation at pass level Monday morning. Through out the day
warm advection should cause those snow levels to rise generally
above 12 kft.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
Issued at 303 PM MDT Sun Oct 12 2025

Moisture from the remnants of TS Raymond will be in place
through Tuesday morning with showers continuing through noon
with showers lessening in intensity and QPF amounts dropping off
quite a bit by Tuesday afternoon, although scattered showers
will still remain over the high terrain. Storm total QPF at this
time is indicating potential for 1 to 2 inches for the southern
valleys included in the watch and upwards of 3 to 4 inches of
precipitation over the San Juan mountains possible starting
tonight through Tuesday morning, so Monday is going to be
another soaker for the San Juans especially after being already
saturated from previous rainfall from TS Priscilla. The Flood
Watch remains in effect from Monday morning through noon Tuesday
including the southwest San Juan Mountains, San Juan River
Basin and Animas River Basin.

Our CWA will be positioned between a deep low pressure trough
over California and high pressure over Texas. This low pressure
trough will swing further east and track over the Great Basin
during the day on Tuesday and enter Utah by Wednesday. This will
help push the direct moisture plume from TS Raymond eastward,
but not completely vacate the moisture as we will still see some
remnant pockets of 100 to 200 percent of normal PWAT anomalies
across the area through Wednesday before the trough sweeps
across the area Wednesday night into Thursday. The pressure
gradient will tighten though ahead of this trough Tuesday
afternoon through Wednesday with H7 winds of 30 to 40 kts. So
Tuesday and Wednesday afternoon could be breezy to windy across
the area with gusts potentially 30 to 40 mph in some locations.
So, we will see scattered afternoon convection favoring the high
terrain each day with the best chances arriving Wednesday
evening into Thursday with the passage of the trough.
Temperatures warm to 5 degrees above normal before dropping to
10 degrees below normal with the trough passage by Thursday.
Snow levels also drop to around 7kft to 8kft so snow is possible
in the high country but amounts appear light at this time. We
will have to keep an eye on potential for freezing temperatures
across some valley locations Thursday night into Friday morning,
especially the northern valleys and the southern valleys as
lows look to drop into the upper 20s. Freezing temperatures
could be seen in some higher valleys in central portions as well
so something to look at as we get closer. Precipitation comes
to an end by Thursday afternoon as much drier air moves in
behind this trough and high pressure builds back into the region
Friday into the weekend, finally cutting off any potential
tropical moisture tap.

&&

.AVIATION /06Z TAFS THROUGH 06Z TUESDAY/...
Issued at 1149 PM MDT Sun Oct 12 2025

Clouds will start increasing from north to south this morning as
moisture returns thanks to TD Raymond. Showers are possible
after 12Z for KDRO and KTEX though chances significantly
increase after 18Z. Remaining TAF sites will also see chances
for showers and rain but this will occur as the morning
progresses. Widespread VFR conditions will continue overnight
but through the day tomorrow periods of MVFR to IFR will be
possible under the heavier rain and showers. KDRO and KTEX will
see the best chances for these lower flight categories. ILS
breakpoints may be reached from time to time for many TAF sites
as indicated in PROB30 groups.

&&

.HYDROLOGY...
Issued at 303 PM MDT Sun Oct 12 2025

The amount of precipitation some areas have received over the
past few days has been exceedingly impressive to say the least.
Looking at 72 hour totals (unofficially), most areas across the
San Juans received between 2 to 4 inches of rainfall with a few
spots reaching just over 5 inches. 1 to 2 inches was common
across central portions of Colorado with anywhere from a half to
1 inch for the northern valleys. Most of eastern Utah received
the same, a half to 1 inch of rain.

The Flood Watch continues for portions of the San Juans and
southern valleys as TD Raymond brings another surge of moisture
from the south Monday into Tuesday. Soil moisture in the watch
area is very high due to all of the rain therefore runoff will
be more efficient for this round. The estimated rainfall totals
did increase with this latest forecast package, so there is a
chance would could see similar impacts.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

CO...Flood Watch from 6 AM MDT Monday through Tuesday morning for
     COZ019-022-023.
UT...None.

&&

$$

SHORT TERM...KJS
LONG TERM...MDA
AVIATION...TGJT
HYDROLOGY...TGJT