679
FXUS65 KPUB 080525
AFDPUB

Area Forecast Discussion
National Weather Service Pueblo CO
1125 PM MDT Sat Sep 7 2024

.KEY MESSAGES...

- Isolated thunderstorms mountains/valleys and I-25 corridor
  this evening, mainly south of Highway 50.

- Slightly warmer Sunday, with isolated afternoon showers and
  thunderstorms once again.

- Isolated to scattered showers and thunderstorms across the
  higher terrain each afternoon and evening through the extended
  period.

- Enhanced fire danger possible on Thursday for portions of the
  plains.

&&

.SHORT TERM /THROUGH SUNDAY/...
Issued at 227 PM MDT Sat Sep 7 2024

Currently...Isolated thunderstorms have returned to srn CO this
afternoon, as increased low/mid level moisture and weak upward
motion from wave sliding se over the 4 corners upper ridge have
combined to generate some weak storms over the ern San Juans/srn
Sangres as of 2 pm. Temperatures have reached the 80s to low 90s at
most lower elevations and across the plains, while mountains and
high valley readings are in the 60s/70s.

For the remainder of the afternoon into this evening, expect
isolated to scattered storms to continue to form over the mountains,
eventually drifting across interior valleys and the I-25 corridor,
especially early this evening. CAMs continue to keep best coverage
of storms south of Highway 50, and HRRR has been consistent in
showing some windy storms developing near Canon City 5-6 pm, which
then move across Pueblo County 6-8 pm. Given rather modest CAPE
(values under 1000 J/KG) and LCLs above 10k feet, expect gusty
outflow winds to dominate most activity, though a brief burst of
moderate rainfall and some small hail will be possible under any
heavier storms. Most convection doesn`t push too far east of I-25
before dissipating 8-10 pm, so won`t extend pops onto the sern
plains at this point. Clouds then clear overnight with seasonably
cool min temps expected.

On Sunday, upper level ridge builds slightly, which will give a 1-3
degf boost to max temps at most locations. Recycled moisture from
Saturday`s storms will likely be sufficient for another round of
afternoon convection over the mountains, though lack of any
significant forcing suggests rather weak/sparse activity. Models
favor the ern San Juans for highest pops, and did add some very low
pops to Kiowa and Baca Counties on the plains where stronger surface
sly flow and weak low convergence could generate a storm or two, as
hinted at by the HRRR. Again, more wind than rain with the majority
of activity, though a brief downpour and some small hail will be
possible with strongest storms.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
Issued at 227 PM MDT Sat Sep 7 2024

Sunday night and Monday...A somewhat flat ridge will be in place
across the region through Monday evening, while an upper disturbance
crosses the Rocky Mt region to the north. Ongoing showers and
thunderstorms Sunday evening are expected to dissipate quickly once
the sun sets. Also, available moisture is limited, so this upper
shortwave, coupled with daytime heating, will likely only help
initiate isolated convection across the mts and high valleys Mon
afternoon and early evening, with activity once again dropping off
quickly with sunset. Minimum Temps Sun night are expected to cool
into the upper 30s to mid 40s for the high valleys, and 50s for the
plains. Highs on Monday will climb to above normal levels with
readings in the 70s to around 80F for the high valleys, and mid 80s
to mid 90s for the plains.

Tuesday and Wednesday...A change in the upper pattern begins to take
place starting Tuesday as the upper ridge over the region pushes off
to the east, and a trough of low pressure off the Pacific NW coast
deepens Tue, then moves onshore across WA and OR on Wed. West to
southwest flow aloft begins to increase both days, and especially on
Wed, drawing some Pacific moisture across the Desert Sw and Four
Corners regions into the western half of CO. A weak shortwave in the
upper flow will serve as the spark for a slight increase in
convection chances across the higher terrain both days, with
scattered pcpn chances forecast for the Continental Divide and the
central mts, and isolated convection for the remaining high terrain.
Plan on highs in the 70s for the high valleys, and mid 80s to lower
90s for the plains.

Thursday and Friday...Upper low located over the Pacific NW by mid-
week will push across ID on Thu, then MT on Fri. This pattern with a
fairly strong trough over the western third of the country will
produce stronger southwest flow aloft across CO, leading to enhanced
downslope flow, continued warm temps and drier conditions. Long
range models are leaning towards a more dry solution across the
higher terrain both days with just isolated showers and storms over
the higher terrain, with the best chances over the central mts.
However, across the eastern plains there is a growing area on Thu
where critical fire weather conditions may develop. Moore

&&

.AVIATION /06Z TAFS THROUGH 06Z MONDAY/...
Issued at 1125 PM MDT Sat Sep 7 2024

VFR conditions are expected at KALS, KCOS, and KPUB through 24
hours. VCSH will be possible at KALS tomorrow afternoon, and if
showers do drift close to the terminal, brief MVFR conditions will
be possible. Otherwise, any passing showers could push out some
gusty outflow, but at this time chances are relatively low.

&&

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

&&

$$

SHORT TERM...PETERSEN
LONG TERM...MOORE
AVIATION...GARBEROGLIO