413
FXUS65 KPUB 171712
AFDPUB

Area Forecast Discussion
National Weather Service Pueblo CO
1112 AM MDT Mon Aug 17 2026

.KEY MESSAGES...

- Drier today and Tuesday with warming temperatures. A few
  thunderstorms are possible on today mainly along the Raton
  Mesa.

- A cold front arrives by Wednesday morning with a round of
  strong to possibly severe thunderstorms along with elevated
  flash flood potential.

- An upper high strengthens overhead for late in the week and
  through the weekend with daily thunderstorm chances across the
  higher terrain and adjacent Plains, and hot temperatures.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 1231 AM MDT Mon Aug 17 2026

Currently...radar shows scattered showers and thunderstorms
spread across the Plains early this morning. Most are stretched
from a Cripple Creek to Kim line, and slowly tracking east. A
few stronger cells could produce small hail and very heavy
rainfall along with lightning. Most CAM guidance has this
activity slowly shifting eastward and dissipating by daybreak.
Temperatures are mild, with upper 50s to mid 60s across the
Plains. Elevated dewpoints should help keep temperatures from
falling by more than a degree or two through morning.

Today and tonight...the upper level high that has been sitting
over the southeast U.S. will build westward into Texas, and
expand northward over the next 24 hours. This will bring
slightly drier air to the region, and help limit shower and
thunderstorm development this afternoon and evening. PWAT values
will fall to less than 1 inch, and CAPE values will only be
around 800 j/kg with higher values out near the Kansas border.
Flow remains southerly in the low levels, which will help keep
dewpoints in the upper 50s to near 60 this afternoon. As the
upper level ridge builds northward, it should help suppress most
convection today. The exception looks like the southern Sangre
de Cristo Range, east along the Raton Mesa. CAM guidance
develops a cluster of thunderstorms over this area, and tracks
it east along the New Mexico border this afternoon and early
evening. Given the instability and moisture parameters, a couple
could become strong, with hail to 3/4 of an inch and 55 mph
winds along with heavy rainfall. Further north along the Eastern
Mountains, shower and thunderstorm activity looks very isolated.
At this time, did not issue a Flash Flood Watch for the Aspen
Acres burn scar given the scarcity of expected thunderstorm
coverage. But given recent heavy rains and flooding issues, if
an isolated cell happens to move over the scar, flash flooding
could occur. Confidence at this time is less than 20 percent
that this would happen. Expect shower and thunderstorm activity
to shift south and east into New Mexico by early evening,
leaving southern Colorado dry through the overnight hours.

Temperatures will warm slightly this afternoon, with mid 80s to
near 90 degrees for the Plains, and 80s for the San Luis Valley.
Overnight lows will remain the 50s and 60s.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
Issued at 1231 AM MDT Mon Aug 17 2026

Models continue to be in good agreement through the extended
period, with NBM guidance starting to catch on to warmer
conditions by late in the week into the weekend.

Tuesday...upper level ridging continues ot build across southern
Colorado with warming temperatures and generally dry conditions
across the region. Temperatures will warm back through the 90s
with a few lower 100s possible near the Kansas border. PWAT
values continue to dry out, and will help limit shower and
thunderstorm activity. A couple of thunderstorms may be possible
during the afternoon and evening from the Central Mountains,
southeast into teh Palmer Divide region as a weak wave tracks
across the area.

Wednesday...a cold front arrives by Wednesday morning turning
low level flow easterly by mid to late morning. Moisture returns
as well with dewpoints reaching back into the upper 50s to
lower 60s across the Plains. Shear also increases, with 0-6km
shear values in excess of 30 kts by the afternoon. Expect
showers and thunderstorms to develop by early afternoon,
initially over the higher terrain, then spreading east into the
Plains. As storms move into the Plains, a few could become
strong to severe with large hail and damaging winds possible. In
addition, heavy rainfall will be possible, along with Flash
Flooding on area burn scars. Temperatures will be cooler, with
80s and lower 90s across the Plains.

Thursday through Sunday..models all in agreement with the upper
high strengthening over the Great Basin, shifting east across
Colorado late in the week and over the weekend. Multiple waves
embedded under the ridge will lift northward during this period,
with daily showers and thunderstorms possible. Most thunderstorm
activity will remain tied to the terrain, with a few slipping
east into the I-25 corridor during the evening before
dissipating. Extended NBM guidance is starting to catch up with
deterministic guidance on high temperatures Friday through
Sunday. Given the strength of the upper high, upper 90s to lower
100s are not out of the question, especially for the weekend.

&&

.AVIATION /18Z TAFS THROUGH 18Z TUESDAY/...
Issued at 1111 AM MDT Mon Aug 17 2026

VFR conditions are mostly expected at KALS, KCOS, and KPUB through
24 hours.

Generally, expecting fewer storms across the region today, with best
chance mid-late afternoon at KCOS for a few hours. KPUB has a very
low chance for any precip, though we will have to monitor for any
outflow this afternoon.

Flow weakens across the terminals this evening, becoming more
variable by early Tuesday morning.

&&

.PUB WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

SHORT TERM...MOZLEY
LONG TERM...MOZLEY
AVIATION...GARBEROGLIO