628
FXUS65 KPUB 121548
AFDPUB

Area Forecast Discussion
National Weather Service Pueblo CO
948 AM MDT Mon Aug 12 2024

.KEY MESSAGES...

- Showers and thunderstorms expected across the region this
  afternoon and tonight. A few could become strong to severe
  across the Plains.

- A few degrees cooler this afternoon.

- Afternoon showers and storms expected Tuesday and Wednesday,
  with the greatest coverage along and around the mountains.

- Some storms may become strong to marginally severe Tuesday
  and Wednesday across the valleys and plains.

- Drier Thursday and Friday, with showers and storms increasing
  in coverage again for the weekend.

&&

.UPDATE...
Issued at 942 AM MDT Mon Aug 12 2024

A Flash Flood Watch has been issued for parts of the forecast
area. Collaboration between BOU along with HREF guidance
indicates the potential for heavy rain capable of producing
flash flooding will be possible over east central CO this
afternoon and evening. If you take guidance as is, the greatest
threat is Crowley and Kiowa counties, but given uncertainty with
these events, included nearby adjacent counties. (If outflow
pushes a bit south, then the US50 corridor over the plains will
be under the gun for flash flooding).

Plenty of moisture. along with the favorable jet dynamics will
allow for thunderstorms to produce heavy rain later today over
the region. /Hodanish

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 348 AM MDT Mon Aug 12 2024

Currently...satellite imagery early this morning shows multiple
waves embedded in westerly zonal flow across southern Colorado.  One
is current departing the Eastern Plains into Kansas, with any
lingering convection ending by 4 AM.  Weaker energy is moving out of
the Central Mountains along the Highway 50 corridor with light
precipitation dissipating as it moves east across Fremont County.
Satellite imagery also shows a wave over far southwest Colorado,
followed by another piece of energy across central Utah.  Both look
to impact our weather through the next 24 hours.  Temperatures are
quite mild, with mid 60s to lower 70s across the Plains.  Moisture
remains in place with elevated dewpoints in the mid 50s to mid 60s
across the Plains.  This should keep the Plains weakly unstable
through morning, with isolated showers possible, especially along
the Highway 50 corridor through daybreak.

Today...flat high pressure to the south will keep westerly zonal
flow across southern Colorado through this afternoon.  The embedded
waves mentioned above will transit east across the state by this
afternoon.  Southeasterly surface flow will keep moisture pooled
across the Plains, with widespread dewpoints in the upper 50s to mid
60s.  SBCAPE values around 1000 j/kg along the I-25 corridor, rising
to near 2000 j/kg near the Kansas border should allow for robust
convection by this afternoon.  Storms will initiate across the
higher terrain by mid morning, then spread eastward into the I-25
corridor this afternoon.  As storms move east, they will encounter
an environment that should allow for strengthening.  0-6 km shear of
30 kts should be sufficient for a few strong to severe storms,
especially as they migrate east of I-25.  Hail to 1.5 inches and
wind gusts in excess of 60 mph will be possible on the Plains with
stronger storms.  Given the high PWAT values near 1.5 inches, storms
will likely be efficient precipitation producers, with elevated
risks of flash flooding on area burn scars and flood prone areas.
Afternoon highs today will be slightly cooler, with mostly 80s
across the Plains, and 70s over the San Luis Valley.

Tonight...showers and thunderstorms will continue through this
evening, especially across the Plains.  Most high-res model guidance
has thunderstorms shifting east into Kansas around midnight tonight.
Expect any severe risk to diminish as well as storms track eastward
into Kansas.  Across the Mountains, showers will likely continue
through the overnight hours along the Continental Divide.  Locally
heavy rainfall will remain possible through the evening hours.
Overnight lows will fall off into the upper 50s to mid 60s by
Tuesday morning.  Mozley

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
Issued at 348 AM MDT Mon Aug 12 2024

Tuesday - Wednesday: Active weather is in store for south central
and southeastern Colorado for the first part of the midweek period.
Southwesterly flow and a shortwave will prevail Tuesday, with a
minor trough passage Wednesday. These features will bring heightened
broad forcing and orographic forcing. Along with the forcing,
moisture will remain in place across the region. With the rise in
forcing and the moisture in place, daily afternoon rain showers and
thunderstorms are expected for much of the area, with the greatest
coverage along and around the mountains. And while coverage of
storms will be less across the valleys and plains, some storms may
become strong to marginally severe during the mid afternoon to early
evening hours, with severe wind gusts and large hail the primary
hazards. With that all said though, as instability starts to wane
during the evening hours, any showers and storms present are
anticipated to dissipate. Looking at temperatures, a warm couple of
days is expected. Much of the region will warm to around seasonal
values for mid August, though storm outflows may help to keep some
areas cooler during peak heating hours.

Thursday - Sunday: The rest of the long term period will see a
pattern "reset" as the monsoon flow reestablishes itself. Thursday
and Friday, a ridge will slowly redevelop behind the aforementioned
trough from earlier in the week. Moisture will become scoured out by
that wave though, and given increased subsidence and no major
forcing, drier conditions are expected, with mostly just isolated
rain showers and thunderstorms along the mountains. Then during the
weekend, the ridge is expected to continue to reorganize and start
to pull better moisture northward again. This influx of moisture
will increase precipitation chances for the area, with showers and
storms rising in coverage, but especially around the Continental
Divide area. Like most Summer days though, showers and storms are
expected to dissipate during the evening hours as instability
lessens. As for temperatures, a slight bump up is anticipated. With
the ridge building, slightly above seasonal temperatures is expected
for much of the region.

&&

.AVIATION /06Z TAFS THROUGH 06Z TUESDAY/...
Issued at 348 AM MDT Mon Aug 12 2024

KALS...a few rain showers will remain possible across
the San Luis Valley through morning with CIGS running 4 to 6 kft.
Showers and thunderstorms will be possible through the afternoon,
especially in the 20-00z time frame.  Gusty outflow winds along with
reduced CIGS and VIS will accompany any convection that moves across
the terminal.  A return to VFR conditions is expected by this
evening.

KCOS and KPUB...VFR conditions this morning with CIGS running around
10 to 11 kft.  Showers and thunderstorms will be possible at both
terminals during the afternoon and evening.  Gusty outflow winds
along with reduced VIS and CIGS will accompany any storms that move
across the terminals.  Southeasterly flow overnight will likely lead
to low stratus across the area, with both terminals seeing reduced
CIGS into Tuesday morning.  Mozley

&&

.PUB WATCHES/WARNINGS/ADVISORIES...
Flood Watch from 3 PM MDT this afternoon through this evening
for COZ081-082-084>086-089-093-095>098.

&&

$$

UPDATE...HODANISH
SHORT TERM...MOZLEY
LONG TERM...SIMCOE
AVIATION...MOZLEY