425
FXUS65 KPUB 180534
AFDPUB

Area Forecast Discussion
National Weather Service Pueblo CO
1134 PM MDT Wed Jul 17 2024

.KEY MESSAGES...

- Scattered afternoon and evening showers and thunderstorms, a
  few strong to severe, especially along and east of the I-25
  corridor.

- Cooler weather is expected to persist into early next week
  with daily chances for showers and thunderstorms capable of
  producing locally heavy rainfall continuing in and near the
  mountains.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 240 PM MDT Wed Jul 17 2024

Current water vapor imagery and upper air analysis indicates weak
west to northwest flow aloft across the region, with the centroid of
the upper high indicated across west central New Mexico at this
time. Water vapor imagery also indicating weak embedded waves with
the flow across the northern and central Rockies, with regional
radars indicating cells already developing over the higher terrain
as of 11 am. GOES blended total precipitable water vapor imagery
indicting PWATS running 100 to 125 percent of normal, with some
drying noted further northwest across the Eastern Great Basin at
this time.  SPC meso-analysis and model data continue to indicate
modest CAPE and shear profiles over and near the higher terrain,
with better instability and shear profiles indicated further east
across the southeast Plains.

With that said, will see scattered to numerous showers and storms to
develop over the higher terrain through the late afternoon and early
evening, with storms pushing east to southeast into a better storm
environment across the I-25 Corridor into the southeast Plains. With
the ample moisture in place and relatively slow steering flow of 15
to 25 mph, heavy rainfall and localized flash flooding will be
possible with all storms today. With CAPE of 500-1500 (along with
DCAPE of 1000-1500) and effective shear increasing to 25 to 35 kts
across the plains, could see strong outflow winds of 60-70 mph and
large hail possible with the strongest storms across the plains this
afternoon and evening.  Latest CAMS are suggesting clouds slow to
clear with some storms continuing across the southeast Plains
through the late evening and overnight hours, as the northern
Rockies embedded waves translate across the eastern Plains. With
moisture in place and slowly clearing skies, overnight lows to be
near to slightly above seasonal levels in the mid 50s to mid 60s
across the plains, and mainly in the 40s across the higher terrain.

For tomorrow, the upper high remains progged to slowly retrograde
north and west into the Four Corners Region. This will bring in
slightly drier air into the region within more northerly flow aloft.
Models do indicate a slower timing of convective initiation,
especially across the southeast plains with some subsidence behind
the passing wave, as another wave across the Northern Rockies
translates across the Central Rockies through the afternoon.
There remains enough moisture to work with the next passing wave
to support scattered to numerous showers and storms across the
region, with the greatest coverage over and near the higher terrain,
with the more northerly flow aloft. Again, can`t rule out heavy
rainers with storms and localized flash flooding, along with the
potential for a few strong wind gusts and hail across the southeast
plains, where the best instability and shear profiles will remain.
Temperatures tomorrow will be at to slightly warmer than today,
especially across the plains with the slower timing of
convection.

&&

.LONG TERM /THURSDAY THROUGH WEDNESDAY/...
Issued at 240 PM MDT Wed Jul 17 2024

Temperatures warm for Friday with the upper ridge axis still
anchored over the western U.S.  This puts CO under continued
northerly to northwesterly flow aloft.  Energy dropping southward
through the northern plains will set up a surface boundary which
shifts south and eastward across the plains Friday afternoon.
Thunderstorms will initiate over the mountains and reinforce the
wind shift across the plains as they move eastward. This will be the
focus for another round of fairly widespread showers and
thunderstorms across the region. Surface dew points dry out along
the I-25 corridor behind the boundary during the late afternoon, and
shear looks weaker as well, though could still be around 30 kts in
the afternoon. With up to 1000 to up to 1500 J/kg of CAPE near the
eastern border, will need to watch for the potential for strong to
severe storms across the far eastern plains, but for now think gusty
outflow winds up to 65 mph will be the primary risk give more
inverted V soundings and higher LCLs.  Some small hail near the KS
border will also be possible where higher CAPE will reside.  We are
not outlooked yet for severe yet, which looks okay given the
marginal nature of the event, but wouldn`t be surprised to see a
marginal risk added if the potential for a gusty outflow wind risk
holds.

A cold front drops through the southeast plains as an upper trough
moves southward from Canada towards the Upper Midwest.  This will
bring cooler temperatures for the weekend with a continued risk of
showers and thunderstorms as recycled monsoon moisture continues to
circulate around the upper high to the west.  Northerly steering
currents should keep storms largely over the mountains, though
outflows pushing off the higher terrain could spread a few storms
into the southeast plains in the afternoon. Deep layer shear is even
weaker on Saturday, so risk of severe looks low at this point though
some elevated CAPE and PWAT ranging from 0.6 to 1.2 will be
sufficient for locally heavy rainfall, maintaining a risk for flash
flooding on burn scars.

Not much change is expected through the extended with the ridge to
the west keeping cooler northerly flow across the region and
sufficient moisture for daily afternoon and evening showers and
thunderstorms, most of which stay over and near the mountains. The
main risk with thunderstorms will continue to be locally heavy
rainfall capable of producing a localized flash flood potential for
burn scars in the mountains. Gusty outflow winds up to 50 to 60 mph
will also be possible along with some brief small hail over the
higher terrain. Temperatures will remain below normal, especially
across the plains and deep layer shears look relatively weak which
should keep storm strengths largely below severe limits.  -KT

&&

.AVIATION /06Z TAFS THROUGH 06Z FRIDAY/...
Issued at 1134 PM MDT Wed Jul 17 2024

For KCOS..MVFR ceilings are possible at KCOS later tonight and into
the early morning hours of tomorrow, due to southeasterly winds and
lingering moisture from today`s showers and storms. Ceilings are
expected to clear by around 15 to 16Z at the latest, with VFR
conditions prevailing until afternoon showers and thunderstorms
develop once again after 22Z. Main risks with storms tomorrow will
be winds up to 60 mph, small hail, lightning, and heavy rain.

For KPUB and KALS..VFR conditions are expected to persist through
the rest of tonight and into the early morning hours of tomorrow,
before our next round of showers and thunderstorms looks to develop
after 22Z over or near both stations. Main risks with storms
tomorrow will be winds up to 60 mph, small hail, lightning, and
heavy rain.

&&

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

&&

$$

SHORT TERM...MW
LONG TERM...KT
AVIATION...EHR