San Luis, Colorado Weather Forecast Discussion

619
FXUS65 KPUB 182011
AFDPUB
Area Forecast Discussion
National Weather Service Pueblo CO
211 PM MDT Thu Sep 18 2025
.KEY MESSAGES...
- Warmer on Friday, with some convection returning to the
  southwest mountains by late afternoon and evening.
- Warmer over the weekend into Monday with only some very
  isolated afternoon thunderstorms over the mountains.
- A cold front will bring slightly cooler air and a small uptick
  in shower and thunderstorm chances starting Tuesday.
&&
.SHORT TERM /THROUGH FRIDAY/...
Issued at 207 PM MDT Thu Sep 18 2025
Currently...The state was situated between a departing upper low
across the upper Midwest, and an upper ridge over the Great Basin
and Desert Southwest, allowing for plenty of sun and dry conditions.
Temps as of 1 PM have warmed into the 60s for the high valleys, and
60s to mid 70s for the plains.
Tonight...Any stray shower that happens to develop across the higher
terrain later this afternoon is expected to be short-lived, and at
most produce gusty erratic winds to 40 mph. The upper ridge begins
to flatten out across Colorado through the overnight hours, allowing
some high clouds to push in across the higher terrain. Plan on
minimum temps tonight in the 30s to near 40F for the high valleys,
and 40s to around 50F for the plains.
Tomorrow...Westerly flow aloft will help boost afternoon high
temperatures on Friday, while a return of some moisture into the
Four Corners region will mean increasing convection chances to the
mts, and mainly the southwest mts, by late afternoon. SPC has
painted a General Thunder area across the southern half of the
forecast area for tomorrow, so main threats will be wind gusts to 45
mph, cloud to ground lightning and brief periods of moderate
rainfall. One thing to note is that the NAM is showing a small
window of enhanced CAPE and bulk shear over Baca County from roughly
noon until 3 PM. High temps tomorrow are forecast to climb back up
to the warm side of normal, with readings in the 70s to near 80F for
the high valleys, and mid 70s to mid 80s for the plains. Moore
&&
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
Issued at 301 AM MDT Thu Sep 18 2025
Flat upper ridge across Colorado Fri/Sat will allow a modest
influx of mainly mid/high level moisture into the state, leading
to an upturn in convection both days. Low levels look to remain
dry, with surface dewpoints in the 30s, and suspect most
activity stay high-based and weak, generating mostly wind and
lightning, but only a few sprinkles or brief light rain. Temps
both days will end up just slightly above average levels, and a
few spots on the plains could get close to 90f Sunday
afternoon.
Flow aloft become nwly Mon as strong upper wave drops into the
nrn plains by afternoon. Expect a continuation of warm temps and
just isolated convection, along with a increase in wind speeds
as lee surface trough deepens. Models seem to have converged on
a late Mon/Mon night cold frontal passage, with perhaps a brief
window for showers/thunderstorms along and behind the front into
Tues morning. Mostly dry and a little cooler Tue into mid-week,
with upper low wallowing around in the lower Mississippi Valley,
keeping weak nwly flow in place across Colorado.
&&
.AVIATION /18Z TAFS THROUGH 18Z FRIDAY/...
Issued at 1119 AM MDT Thu Sep 18 2025
VFR conditions anticipated across the forecast area over the next 24
hrs, including the three main TAF sites of KCOS, KPUB and KALS.
Surface winds are expected to be diurnal in direction and generally
under 12 kts.
&&
.PUB WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SHORT TERM...MOORE
LONG TERM...PETERSEN
AVIATION...MOORE

NWS PUB Office Area Forecast Discussion