Cotopaxi, Colorado Weather Forecast Discussion

709
FXUS65 KPUB 082336
AFDPUB
Area Forecast Discussion
National Weather Service Pueblo CO
Issued by National Weather Service Denver CO
535 PM MDT Mon Sep 8 2025
Key Messages:
- Slight uptick in storm activity tomorrow with potential for
stronger storms across the far southeast plains.
- Temperatures at to slightly above seasonal levels with daily
chances  of afternoon showers and storms over and near the higher
terrain through mid week.
- Cooler late week with greatest coverage of showers and storms
Friday (highest chances still over the mountains), then drier again
into the weekend.
&&
Short Term through Tuesday:
Current water vapor imagery has modest westerly flow aloft across
the region, as a broad upper trough across the West Coast is
ejecting short waves through upper level ridging in place across the
Intermountain West and Rockies at this time. Temperatures, as of 1
pm,  have warmed into the 80s across the plains, with readings
mainly in the 60s and 70s across the higher terrain.  Regional
radars are indicating a few showers and an isolated storm across the
higher terrain, with SPC meso-analysis indicating CAPE of less than
500 j/kg over and near the higher terrain, though does have CAPE up
to 2000 j/kg across the far southeast plains at this time. DCAPE of
800-1300 j/kg is also in place.
Rest of Today and Tonight...
Latest model data continues to support fairly isolated high based
showers and storms over and the higher terrain through the early
evening, with drier air mixing down across the far southeast plains
through the late afternoon limiting instability into the evening.
Showers and storms that do develop will be mainly high based, with
gusty outflow winds up to 50 mph the main threat through the
evening, with slowly clearing skies through the overnight hours and
near seasonal overnight lows once again. Will need to monitor any
convection across western Kansas, though, as a some data supports
increasing instability through the overnight hours, and the
potential for convection early Tuesday morning across the far
southeast plains.
Tuesday...
Flow aloft becomes slightly more southwest through the day, with
model data supporting increasing available moisture with PWATS of
100 to 125 percent of normal into the afternoon. This will support
better coverage of showers and storms over and near the higher
terrain tomorrow afternoon, with better chances of seeing measurable
rain. Further east across the plains, lee troughing will develop
southerly flow with progged CAPE of up to 2000 j/kg in place in the
afternoon, along with bulk shear of 30-40kts. Latest SPC guidance
indicates a marginal risk of severe storms across the far southeast
plains, with strong winds and large hail being the main risks if
storms can develop. Temperatures tomorrow will remain at to slightly
above normal with highs in the 80s to lower 90s once again across
the plains, and mainly in the 60s and 70s across the higher terrain.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
Issued at 245 pM MDT Mon Sep 8 2025
Wednesday and Thursday pretty much have the same weather impacts
each day as a closed low stalls over the US West. Each day there
will be weak waves that pass over Colorado. The current thinking is
that each of the waves will spark thunderstorms over the mountains
and mountain valleys during the mid afternoon and then develop
further to the east before dissipating before shortly after sunset.
The main hazards from the storms appear to be locally heavy rain and
gusty outflow winds. The instability really isnt there each of
these days, so the severe hail risk is low. However, the DCAPE
values each day are above 1000 J/kg, so perhaps isolated 60 MPH wind
gust will develop. High temperatures will be persistent with values
in the 80s to 90s over the plains and the 60s to 70s over the
mountain valleys.
Friday through Sunday...The closed low finally breaks free of
being stalled over the US west and ejects over northwest
Colorado. The wave will be the strongest wave of the week, which
will spark more widespread showers and thunderstorms over the
mountains, mountain valleys, and the adjacent plains. MUCAPE
values are less than 1000 J/kg, so the severe risk for hail is
low. The thermodynamic profile over the San Luis Valley is a bit
concerning because of how saturated the profile is  I think
there may be a sneaky heavy rain and flash flood risk over the
mountains and the mountain valleys as the wave passes overhead
on Friday. The profile over the plains have a large T  Td
spread, so the gusty outflow winds are expected. Saturday and
Sunday look drier as the heights rise after the trough passes
overhead with perhaps an isolated thunderstorm over the
mountains.
&&
.AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/...
Issued at 535 PM MDT Mon Sep 8 2025
VFR conditions are likely during the next 24 hours at all 3 taf
sites, KPUB, KALS and KCOS. There may be some quick moving
convective showers this at the beginning of this taf period which
may cause some brief gusty winds, otherwise winds will become light
and diurnally driven.
Diurnal flow is anticipated tomorrow at each taf site. Chances of
convective showers are low tomorrow and decided to leave any mention
of convection out of tomorrow afternoons TAFs.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SHORT TERM...WFO PUB
LONG TERM...WFO PUB
AVIATION...WFO PUB

NWS PUB Office Area Forecast Discussion