302
FXUS65 KGJT 012317
AFDGJT

Area Forecast Discussion
National Weather Service Grand Junction CO
417 PM MST Sun Nov 1 2026

.KEY MESSAGES...

- The Flood Watch continues for southeast Utah and southwest
  Colorado as an atmospheric river brings rain, rainshowers, and
  snowfall to the area.

- Several rivers across southwest Colorado are forecast to reach
  minor flooding stage.

- The San Juan River at Pagosa Springs is forecast to reach
  major flood stage which has prompted a Particularly Dangerous
  Situation Flood Warning for that area.

- Winter weather highlights have been issued for the San Juans
  and central Colorado mountains for accumulating snow Sunday
  morning through Monday evening.

&&

.DISCUSSION...
Issued at 1148 AM MST Sun Nov 1 2026

A substantial stream of atmospheric river moisture continues to
spread across the region this afternoon. Widespread rainfall
persists below 11000 feet. This has already produced a
streamflow response on rivers in southwest CO. Well over an
inch of rain has fallen across southwest CO in the past 24 hours
and more is on the way. Flood warnings are in place for the La
Plata, Mancos, San Juan and Navajo rivers due to the forecasted
volume of water that`s expected to pass through these basins.
Widespread rain showers, including some embedded thunderstorms,
will bring valley rainfall to near an inch for the central
valleys, and 2 to 2.5 inches for the Four Corners valleys
eastward, with less up north. 1.5 to 2.5 inches is likely for
the Book Cliffs/Tavaputs and central mountains while the San
Juans may see 3 to 4 inches of liquid precipitation. The Flood
Watch remains in effect for southeast Utah and southwest
Colorado accounting for saturated soils and excessive rainfall
producing additional localized flooding and debris flows near
susceptible washes, arroyos and burn scars.

Winter Weather Conditions:

Snow levels will remain above 10K feet, before dropping late
this afternoon onwards. Amounts remain in the 12 to 18 inch
range with locally higher amounts possible keeping Winter Storm
Warnings in effect. The Advisories also remain in place for the
central mountains, Grand Mesa, and Flat Tops where 5 to 10
inches of snow are expected. As snow levels lower late Sunday
night into Monday morning, some of this snow will reach pass
level. Be prepared for winter driving conditions during the
Monday morning commute along US-550, US-50, and along I-70 over
Vail Pass, with lighter impacts north on highway 40 west of
Rabbit Ears Pass.

NEXT WEEK:

Behind this system, conditions dry out for a few days as high
amplitude ridging moves overhead. We`ll see a slight warm up through
the mid-week period, although highs remain 5-10 degrees below
normal for early November. Looking further out, a quick moving
clipper system has the potential to bring some light showers to the
region mid-to-late next week, although model agreement is poor.

&&

.AVIATION /00Z TAFS THROUGH 00Z MONDAY/...
Issued at 414 PM MST Sun Nov 1 2026

MVFR/IFR conditions are expected at most TAF sites for the rest
of today, with periodic conditions below ILS breakpoints
through the TAF period. Gusty winds will be around this evening
and through the overnight hours at some TAF sites. Winds will
begin to settle down after ~03Z, but showers will continue
through ~12Z with rain changing over to snow at higher elevation
TAF sites overnight. Therefore, lowered ceilings and persistent
precipitation will continue to impact terminals through the TAF
period.

&&

.HYDROLOGY...
Issued at 1148 AM MST Sun Nov 1 2026

An atmospheric river will produce widespread rainfall with
stronger rain rates across southeast Utah and southwest Colorado
this afternoon through Monday, mostly below 10,000 feet. A
growing concern lies in the potential for runoff around steep
terrain in the region. This could produce rock, mud, and debris
flows onto roadways, as well as flash flood prone burn scars,
washes, slot canyons, and arroyos. Current guidance supports 1
to 3 inches of rainfall for far southeast Utah and portions of
southwest Colorado, with locally higher amounts close to 4
inches possible. As a result, a Flood Watch remains in effect 5
AM Sunday through 11 AM Monday. Latest forecast guidance has a
number of rivers in southwest Colorado climbing above minor
flood stage, with the gage at Pagosa Springs now expected to hit
Major flood stage. As a result, targeted River Flood Warnings
along the La Plata, Mancos, Navajo, and San Juan rivers are in
effect.

Of note, the River Flood Warning for Pagosa Springs is a
Particularly Dangerous Situation due to the significant and
possibly historic flooding along the San Juan River. Excessive
runoff in these basins will exacerbate historic rainfall
totals. That region should prepare for a dangerous and impactful
flood event.

Outdoor enthusiasts, motorists, and residents of areas recently
impacted by flooding are encouraged to remain tuned to the
forecast in the coming days.

&&

.GJT WATCHES/WARNINGS/ADVISORIES...

CO...Winter Weather Advisory until 6 PM MST Monday for COZ009-010-
     012-013.
     Winter Storm Warning until noon MST Monday for COZ018-019.
     Flood Watch through Monday morning for COZ019-021>023.
UT...Flood Watch through Monday morning for UTZ022-028-029.

&&

$$

DISCUSSION...TGJT
AVIATION...TGJT
HYDROLOGY...TGJT