973
FXUS65 KPUB 012352
AFDPUB

Area Forecast Discussion
National Weather Service Pueblo CO
452 PM MST Sun Nov 1 2026

.KEY MESSAGES...

- Heavy rainfall will continue across the ern San Juans into the
  evening, with significant and dangerous flooding expected from
  the mountains downstream into the western edge of the San Luis
  Valley.

- Snow level finally drops late tonight, with several inches of
  snow above 9000 feet in the San Juans before precip ends
  Monday.

- Runoff from heavy rain today and tonight will likely cause
  flooding along the Rio Grande from Mon-Wed, especially from
  South Fork downstream to Alamosa. Flooding is also likely
  along the Conejos River.

- Dry and warmer on Tue, then a weak weather system will bring a
  chance of showers to much of the region Wed into early Thu.

&&

.SHORT TERM /THROUGH MONDAY NIGHT/...
Issued at 212 PM MST Sun Nov 1 2026

After a bit of a lull in precip rates around midday, early
afternoon observations and radar data suggest rainfall is
increasing in coverage and intensity this afternoon over the
San Juans and adjacent areas, with snow level climbing toward
11k feet across the area. Most CAMs suggest period from now (2pm
MST) until around 10 pm will see the heaviest rainfall, with
additional QPF of over 2 inches possible by midnight, then
rain changes to snow above 9000 feet and rates decrease by
sunrise on Mon. Combo of snow and wind could make for difficult
travel over Wolf Creek and Cumbres Passes Mon morning, with
Winter Storm Warning in effect until midday Mon. Overall,
current set of flood highlights for the area look in good shape,
but expect we`ll see multiple areal/river flood warnings later
today and tonight, as run-off hits area waterways and heads
downstream. Elsewhere, scattered showers expected to continue
over the higher terrain this afternoon and evening, with perhaps
a few quick moving showers/thunderstorms on the plains this
evening, before downslope drying ends most activity along/east
of the mountains and across the plains after midnight.

On Monday, upper low moves through Colorado, with strong surface
cold front sweeping southward through the plains during the late
morning hours. Over the mountains, switch to more west and
eventually northwest upper flow should decrease precip
intensity/coverage over the San Juans through the morning, while
snow picks up in the central mountains as snow levels fall and
upward motion increases. Higher elevations from Monarch Pass
northward could see a few inches of snow and some
blowing/drifting by afternoon, though accumulations look low
enough to preclude issuance of an advisory at this point. Over
the eastern mountains and plains, strong north winds will
develop by afternoon behind the cold front, with enough upward
motion for fairly widespread showers/isolated thunderstorms from
early afternoon into early evening, though focus for precip
will shift toward the NM border/srn I-25 corridor fairly quickly
as precip hole develops over COS/PUB (though 18z HRRR has a
bullseye of heavier precip over COS/PUB around noon before
activity shifts south). Could get cold enough for some snow
showers along the Palmer Divide Mon evening before lift exits
the area into the plains by midnight.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
Issued at 212 PM MST Sun Nov 1 2026

After a drier/warmer day on Tue, most model solutions have
latched onto some weak energy sliding through the Rockies
Wed/Thu, generating low elevation rain/mtn snow showers across
the region especially Wed/Wed night. Still not expecting heavy
precip as system continues to look moisture-starved, though
some light snow accumulations over the higher mountains look
possible. End of the week/weekend upper trough position
continues to shift east, suggesting most impacts and precip
will be east of the area, though associated cold front may
bring some brief light sprinkles and cooler temperatures to the
region on Fri.

&&

.AVIATION /00Z TAFS THROUGH 00Z TUESDAY/...
Issued at 452 PM MST Sun Nov 1 2026

Upper low pressure system crossing the Great Basin and Rocky Mt
region over the next 24 hrs will bring widespread rain, low clouds
and deteriorating conditions across much of the forecast area,
affecting the three main terminal sites of KCOS, KPUB and KALS.

KCOS: MVFR to IFR conditions now through 18z due to RA and low cigs.
Mentioned wind shear starting at 06z and lasting through 11z. Front
pushes through by midday with N gusts to 32 kts and -SHRA.

KPUB: MVFR to IFR conditions through 06z due to RA and low cigs.
Mentioned wind shear starting at 12z and lasting through 19z. W-SW
winds gusting gusting to around 20 kts through the early morning,
then front pushes through by midday with N gusts to 32 kts and -SHRA.

KALS: Strong S winds gusting 30-40 kts. MVFR conditions, with
intermittent IFR due to reduced visibility from RA.

&&

.HYDROLOGY...
Issued at 112 PM MST Sun Nov 1 2026

Forecast of significant flooding remains on track for the San
Juans and wrn San Luis Valley, with many locations in the
mountains already seeing rainfall amounts as of late morning in
the 1-2 inch range, with another 2 inches possible by late
evening. Snow level did dip down to around 10000 feet this
morning, but has risen toward 11000 feet at midday, with
observations and webcams showing mostly rain around Wolf Creek
Pass with temps in the 30s, and a few locations farther south
above Platoro Reservoir have warmed into the 40s. Even a few 50s
up to 9000 feet toward the NM border. Snotels have begun to show
drops in SWE (Snow Water Equivalent), suggesting melting snow
will begin adding to river flows for the next 12 hrs or so.
Switch to snow this evening still looks slow initially, before
snow level drops quickly below 9000 feet by sunrise Mon. Total
precipitation amounts of 3-4 inches look on track by late
morning Mon, with a large portion of this falling as rain today
and tonight below about 12000 feet. Rainfall amounts in the
Valley itself should be between .5 and 1.5 inches, heaviest near
the mountains on the western in edge.

Runoff peak should be this evening in the mountains, before
snow level falls and run-off starts to decrease early Mon
morning. River stage forecasts continue to indicate significant
flooding, with the South Fork of the Rio Grande at South Fork
and the Conejos River at Mogote rising well above flood stage
this evening, cresting overnight into early Monday morning.
These high flows will then move downstream Mon/Tue/Wed with
flooding likely on the mainstem Rio Grande at Del Norte/Monte
Vista and Alamosa and along the Conejos River east of Mogote
through the period. A river flood warning has been issued for
the Rio Grande at Del Norte, and a flood watch is now in effect
for the Rio Grande at Alamosa. A areal flood watch also remains
in effect for all of the San Luis Valley from tonight into Tue
morning, mainly for mountain runoff.

Overall, most streams and rivers will likely crest at or
slightly above levels seen during the flood event last week,
with moderate to major flooding likely once again.

&&

.PUB WATCHES/WARNINGS/ADVISORIES...
Flood Watch through Monday morning for COZ067-068.
Winter Storm Warning until 11 AM MST Monday for COZ068.
Flood Watch through late Tuesday night for COZ069>071.

&&

$$

SHORT TERM...PETERSEN
LONG TERM...PETERSEN
AVIATION...MOORE
HYDROLOGY...PETERSEN