956
FXUS65 KPUB 151017
AFDPUB

Area Forecast Discussion
National Weather Service Pueblo CO
417 AM MDT Wed May 15 2024

.KEY MESSAGES...

 - Increased chances for scattered strong to severe storms, capable
   of producing large hail and wind gusts to 60 mph, this
   afternoon into the early evening, for areas along and east of
   I-25.

 - Locally heavy rainfall is appearing likely today, with a low
   risk of flash flooding at this time.

 - Uptick in showers throughout Thursday, with greatest
   coverage during the afternoon, with showers dissipating
   during the evening.

 - Relatively quieter weather for the end of the week and through
   the weekend, though isolated to widely scattered showers
   will be possible.

 - Active weather returns for early next week, with showers for
   some, and critical fire weather conditions possible for the
   plains.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 412 AM MDT Wed May 15 2024

Upper trough in place across the region this morning with once
again, the stronger vorticity maxima staying just to the north.
However, shortwave energy noted on latest satellite imagery
continues to stream overhead, and with a fair amount of cloud cover
and some isolated showery development in place. Do think precip
chances will remain low this morning given the deep westerly flow,
along with some drier conditions in place. With the arrival of a
cold front and with at least scattered mid and high clouds in place
this morning, most of southern Colorado will observe cooler
temperatures today. Didn`t really make too many changes to today`s
high temps, with 60s expected across the mountain valleys and 60s to
70s expected over the plains. Similar precip trends expected for
much of the morning with most locations staying dry, however, will
see isolated showers begin to develop across the higher terrain by
late morning into the midday time frame.

Trends early this morning have been indicating increasing chances
for strong to severe storms across the plains this afternoon into
the evening. Previously mentioned upper trough will dig later this
afternoon, with additional shortwave energy pushing overhead along
with an additional upper trough axis moving into Colorado.
Meanwhile, above mentioned front will continue to spill south across
the plains, with northeast to east winds ushering in higher dewpoint
air. Most guidance in fair agreement with this trend, and even
showing the mid to upper 40 degree dew points pushing right into the
higher terrain and mid Ark Valley. While we may see daytime mixing
assist with lowering these dew points some, I don`t think the dew
points will fall too much. Forecast soundings are showing this trend
and can`t argue given higher dew points upstream and steady
easterlies in place, along with the mid/upper clouds overhead. As
this is occurring, will likely see two separate surface trough axes
develop this afternoon, one across the Pikes Peak region and
another one by the Raton Mesa. Lastly, 700mb winds veer easterly
while increasing, all setting the stay for a fair amount of large
scale ascent and focus for thunderstorm development this afternoon
into the evening. Initial development looks to be focused in these
areas by early afternoon, with coverage and intensity of this
development increasing during the afternoon hours, while also
pushing east into the remainder of the plains.

Building instability in this higher dewpoint air looks to support
areawide CAPE values of 500-1000 j/kg across much of southern
Colorado this afternoon. The higher dew point air will help support
pockets of CAPE values in the 1000-1500 j/kg range across the
plains. One pocket looks to be right up against the higher terrain
and into the I-25 corridor, and another pocket over the far southeast
plains, along and east of a Kim to Lamar line. With this
instability, the above mentioned forcing, along with bulk shear
values of 35-45kt, think the increased chances for strong to severe
storms is warranted over most of the plains. Once again, model
trends this morning are supportive of this, along with HREF output
showing probabilities greater than 50-60% for CAPE greater than 750
j/kg, CIN greater than -25 j/kg, and 0-6km bulk shear greater than
30kt within both of the areas mentioned above. Expected hazards in
this setup today are large hail to the size of half dollars and wind
gusts to 60 mph. Additionally, given the higher moisture air with
focus and instability right into the higher terrain and urban
corridor, expect locally heavy rainfall along with a low risk of
flash flooding. Once again, given the focus right into the higher
terrain, there is also a low chance for impacts to the Decker and
Spring burn scars. Additionally, no real changes to the setup well
into the evening with easterly moist upslope flow supporting
additional showers and thunderstorms over the southeast mountains
and I-25 corridor. So, while the severe risk lowers into the
evening, the risk for additional for heavy rainfall will remain.

&&

.LONG TERM /THURSDAY THROUGH TUESDAY/...
Issued at 412 AM MDT Wed May 15 2024

Thursday: Showery and active weather continues for the Thursday
timeframe. Messy flow is expected over south central and
southeastern Colorado as two systems continue to interact as they
push to the south and southeast. With this pattern in place, broad
forcing is anticipated over the region, with more focused forcing
along the mountains. Given the ascent over the area, showers are
expected to be ongoing during the early part of Thursday, though
primarily over the mountains. Then as the day progresses and
instability rises, scattered showers will increase in coverage,
though again, the greatest coverage of showers will remain along the
mountains given better forcing. Given the modest instability
present, weak thunderstorms will be possible. With that all said, as
the systems exit the area, and instability lessens, showers across
the region will quickly weaken and dissipate during the evening,
with dry conditions then prevailing overnight. As for temperatures,
a cool day is anticipated given the unsettled pattern overhead. Much
of south central and southeastern Colorado will remain around
and slightly below seasonal values for mid May.

Friday - Sunday: For the end of the week and into the weekend,
relatively quieter weather is expected. Flow will become more zonal
as a ridge develops to the south of the region. Given the lack of
any major forcing with this pattern, dry conditions are expected,
with the exception being isolated to widely scattered showers over
the mountains given minor orographics. With that all said though,
two features may increase precipitation chances further, with a cold
front dropping southward Saturday and a disorganized shortwave
ejecting over the area Sunday. Both features will bring modest
upticks in forcing and could help blossom additional showers across
the mountains and plains. Looking at temperatures, rebound to warmer
temperatures is anticipated, even despite the minor cold front
Saturday. Much of the region will warm to above seasonal values.

Monday - Tuesday: For the start of next week, an uptick in active is
expected for south central and southeastern Colorado. The zonal flow
in place will start to become more meridional, and more troughing is
anticipated over the region, which ensemble model guidance are in
decent agreement on. Precipitation chances will rise for portions of
the area, particularly the mountains, as forcing starts to increase.
With that said though, there are signals the plains will become dry
slotted with this pattern, which is evident in ensemble model
guidance QPF fields. Given that, critical fire weather conditions
will be possible across the plains, though recent moisture and
greenup of grasses and brushes may limit large fire growth
potential. Finally, temperatures during this period will vary
between the two days. Monday will be warmer ahead of the system,
while Tuesday will experience a cool down as cold front drops
southward.

&&

.AVIATION /06Z TAFS THROUGH 06Z THURSDAY/...
Issued at 412 AM MDT Wed May 15 2024

Relatively quiet across the TAF sites early this morning, with mid
and high clouds in place along with some very isolated light
showers. Do think the terminals will stay dry for the morning time
frame though. Cold front currently pushing south across the plains
and is currently moving across COS. At this time, increased
northerly speeds and gusts are being observed with FROPA, but think
any stronger gusts will remain limited to here over the next 1-2
hours. Some lower ceilings have developed just to the north of COS,
along the Palmer Divide. Given the northerly component to the winds,
expect any lower ceilings to stay just to the north of COS this
morning.

An active day is appearing likely for all of the terminals, and
especially the COS and PUB sites. Showers and thunderstorms are
expected to develop by midday and early afternoon, with increasing
chances for this precip to move across the terminals during the
afternoon hours. Chances look similar at all sites, but think there
is some slightly higher chances for COS and PUB. While confidence is
lower on exact impact, strong to severe storm development is
possible near the COS and PUB sites and if impacted, large hail and
damaging wind gusts would be the main hazards. The risk of
thunderstorms lowers this evening, but additional showers will be
likely well into the evening hours. This will assist with lowering
ceilings, with at least low end MVFR ceilings likely developing
tonight into early Thursday morning&&

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

&&

$$

SHORT TERM...RODRIGUEZ
LONG TERM...SIMCOE
AVIATION...RODRIGUEZ