446
FXUS65 KPUB 242057
AFDPUB

Area Forecast Discussion
National Weather Service Pueblo CO
257 PM MDT Sat May 24 2025

.KEY MESSAGES...

- Strong to severe thunderstorms possible through this evening
  for the Pikes Peak region, and potentially again tomorrow
  confined to the southeast mountains and adjacent
  valleys/portions of the I-25 corridor.

- Scattered to numerous showers and thunderstorms again on
  Monday, though severe threat looks lower.

- Active weather continues Tuesday through Saturday with daily
  chances for afternoon and evening showers and thunderstorms.

- Temperatures will begin to warm from mid to late week, back
  into the 80s by Friday and Saturday.

&&

.SHORT TERM /THROUGH SUNDAY/...
Issued at 218 PM MDT Sat May 24 2025

Easterly upslope flow has advected 50 dew points westward into
the eastern slopes of the southeast mountains and plains, with
breaks in the clouds and sufficient heating yielding mixed layer
CAPE up to 1500 J/kg across the Pikes Peak region as of 19z.
CAMs and SSCRAM have been progressively showing higher
probabilities for one or two strong to severe storms over Teller
and El Paso counties where deep layer shears are running 40-50
kts. Severe thunderstorms look likely, though majority of the
models play the highest probabilities along the northern Teller
and Northern El Paso county line. Given strong southeast upslope
flow gusting to 25 kts and surface temperatures in the 70s,
think lift is conceptually sufficient to break through the
remainder of the cap across El Paso and eastern Teller counties.
Straight line hodographs suggest splitting supercell storm
modes, however, any deviant southeasterly storm motions, which
could tap richer theta-e air feeding into this region could
enhance low level hodograph curvatures. So isolated tornadoes
are very much plausible. Otherwise, hail up to 2 inches in
diameter (or a slightly larger) and wind gusts up to 65 mph will
be the more dominant risks into the evening. Severe
thunderstorm watch 318 has already been issued and continues
through 8 PM.

Will also need to watch locations to the south, including eastern
Fremont and Pueblo counties closely, though these areas look to stay
more capped.

Farther east across the plains, the airmass gets progressively more
capped with a lower 80 degree convective temperature required to
break through. With lack of a strong shortwave, strong to severe
thunderstorms look even less likely to occur east of the I-25
corridor counties, unless we can get sufficient forcing from a low
level jet later tonight. For now, this looks more like a broad
overrunning case as the upper trough approaches tonight.  Stratus
will redevelop and spread westward across the plains into the lower
eastern slopes of the mountains with widespread showers and drizzle
developing after midnight. Farther east, there could be sufficient
overrunning to release some elevated CAPE and produce some embedded
convective elements/thunder.  Will allow pops to increase overnight
across the plains as NBM suggest but will cap most areas in the
scattered category.

Tomorrow looks cooler with clouds more likely to persist across the
southeast mountains and plains through Sunday.  Where they do clear
along the eastern mountains and adjacent valleys, CAPE of up to 1500
J/kg and deep layer shears of 50+ kts may support one or two strong
to severe storms.  Think the risk area will be in a narrow ribbon
over the southeast mountains and adjacent lower elevations with
locations like the Wet Mountain Valley and Fremont county having the
greatest severe thunderstorm potential. Large hail and damaging
winds look like the primary risks for now. Once storms move eastward
into the plains, storm strengths should decrease as they encounter
cooler, more stable air.  High temperatures on Sunday will stay in
the low to mid 60s across the plains.

For the western areas it will continue dry and breezy for the
western mountains and interior valleys through the 24 hour period.
There may be a better chance for showers and thunderstorms across
northern portions of the San Luis Valley and Chaffee and Lake
counties on Sunday as some low level moisture penetrates westward.
Temperatures will cool off a couple degrees as the upper trough
approaches out west.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
Issued at 218 PM MDT Sat May 24 2025

Upslope on the plains deepens again Sunday night, reinforced by
outflows from nrn Colorado evening convection. Expect widespread
low clouds/drizzle/showers along and east of the mountains
through the night as a result, with perhaps an isolated
thunderstorm possible on the plains where some weak elevated
instability develops. Overall, best forcing for precip looks
mostly north of the area, with grids showing a rather high
pop/low qpf set-up across the eastern mountains and plains.

Upper trough drifts eastward through Colorado on Monday,
leading to moderate instability(CAPE 500-1000 J/KG)/steep lapse
rates with cold pool aloft, but less in the way of shear (0-6km
shear around 30 kts) as stronger low/mid level flow is pushed
south and east of the area. As a result, storm coverage Monday
afternoon/evening will increase across the region, especially
mountains and I-25 corridor where instability will be greatest,
lesser chances over the far sern plains where persistent low
clouds and cool temps will limit storm strength/coverage.
Sounding profile hints at storms on Monday potentially producing
large amounts of small hail, with lack of shear/modest instability
tending to limit hail size.

Upper forcing weakens Tue with brief short wave ridge developing
across Colorado behind departing trough. Still plenty of
moisture and instability left-over across the area in the
afternoon however, and expect scattered showers/thunderstorms
initially developing over the mountains, then drifting across
lower elevations by late day. Severe storms not expected, but
some small hail and local downpours likely. Unsettled weather
persists through the rest of the week into the next weekend, as
weak western U.S. upper trough drifts toward the region and
moisture remains in place, and expect afternoon/evening
thunderstorms each day. Temps will eventually warm back toward
seasonal levels as mid level temps warm slightly, though any
significant early summer heat looks to hold off at least another
weak.

&&

.AVIATION /18Z TAFS THROUGH 18Z SUNDAY/...
Issued at 1130 AM MDT Sat May 24 2025

Cigs have lifted back into VFR category over KCOS and KPUB and
will stay in the VFR category through the afternoon. KCOS could
see a strong to severe thunderstorm this afternoon and although
impacts could stay north of the terminal, the probability is
great enough for inclusion in a Prob30 group for TSRA from
22z-02z. If enough instability develops, large hail could occur
at the terminal. KPUB will likely stay too cool and stable for
thunderstorms this afternoon. Both terminals will see IFR to
LIFR cigs and vis with -SHRA, -DZ and BR spread in after 06z
with much slower improvement on Sunday.

KALS will stay VFR with breezy dry southwest winds gusting to
around 25 kts spreading into the terminal in the afternoon.
Winds will decrease this evening with a similar trend for
Sunday. -KT

&&

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

&&

$$

SHORT TERM...GARBEROGLIO
LONG TERM...PETERSEN
AVIATION...KT