696
FXUS65 KPUB 291736
AFDPUB

Area Forecast Discussion
National Weather Service Pueblo CO
1136 AM MDT Sat Jun 29 2024

.KEY MESSAGES...

- Cooler today with another round of thunderstorms, a few
  strong to severe along the southeast mountain/adjacent plains
  interface and southern plains south of highway 50.

- Scattered rain showers and thunderstorms are expected Sunday
  for much of the region.

- Strong to severe thunderstorms will be possible Sunday, with
  the greatest concern for severe weather across the plains,
  where all severe weather hazards will be possible.

- Rain showers and thunderstorms expected each afternoon Monday
  through Wednesday.

- Drier conditions return for the later half of the upcoming
  week.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 403 AM MDT Sat Jun 29 2024

The cold front has pushed through the southeast plains this morning
with a few more hours of northerly wind gusting up to 35 mph
possible before 0900. Winds will shift around from the east this
afternoon advecting 50s to lower 60 dew points back towards the
mountains by this evening. Heights aloft rise today as the upper
ridge to the south edges northward, however this also brings the
subtropical moisture tap northward into southern sections of the
area by afternoon. With weak perturbations embedded within this
flow, isolated thunderstorms will develop over the mountains around
noon, and gradually spread eastward into the adjacent plains by
early evening.  Soundings look capped across the far eastern plains
today, but some CAMS do spread convection eastward across the plains
during the evening and overnight hours as the low level jet
intensifies and upglides overtop the front to the south resulting in
elevated overnight convection.

Much of southeast CO is outlooked under a Marginal risk for severe
thunderstorms today as deep layer shear increases. The higher CAPE
will likely hug the southern I-25 corridor and southern plains south
of highway 50 today...in better proximity to the front. It will be
dependent on timing of the advection of 50 dew points back westward
towards the I-25 corridor this afternoon as to how much CAPE will be
available during prime afternoon heating, especially north of
highway 50. However given the shear in place (40 kts) and potential
for CAPE up to 1000 J/kg across southern areas, one or two severe
thunderstorms will be possible, with the most favored areas in the
lee of the southern Sangres and the Raton Mesa region.

High temperatures today should be quite a bit cooler than yesterday,
especially across the plains where highs get knocked back into the
80s.  Overnight lows will remain on the warm side given persistent
cloud cover and stratus development across the plains. -KT

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
Issued at 403 AM MDT Sat Jun 29 2024

Sunday: The end of the weekend is expected to bring some busy
weather to south central and southeastern Colorado. Synoptically,
southwesterly to westerly flow will prevail as the area sits between
a ridge to the southeast and more dynamic flow to the northwest, and
then within that flow, a minor shortwave will drift over the region.
Along with that, winds at the surface will take on a more
southeasterly component, and advect rich moisture into the area,
though mostly over the plains. With the uptick in forcing from the
shortwave and the abundant moisture streaming into the area,
scattered rain showers and thunderstorms are anticipated, with the
greatest coverage of precipitation during the afternoon and early
evening hours. Showers and thunderstorms will initially blossom
along the higher terrain during the early afternoon, with showers
and thunderstorms expanding across the valleys and plains during the
mid to late afternoon. Along with all of that, strong to severe
thunderstorms will be possible, particularly across the plains. At
this point, deterministic and ensemble model guidance are in strong
agreement of at least mid 60 dewpoints streaming over the plains
(though how far west is still in question) and moderate instability
materializing where moisture is highest, with uptrends in shear.
This environment will support organized convection, with supercells
possible, capable of severe wind gusts and large hail. In addition
though, with recent uptrends in shear and low level veering winds,
there is an increasing concern for a tornado or two across the
plains. With all of that said though, there is a glaring failure
mode for severe weather across the plains, and that is will there be
enough forcing to pop convection and then sustain it? If forcing is
too weak, then thunderstorms will remain more tied to and
immediately around the terrain, where as if it`s stronger,
synoptically and/or at the surface, then thunderstorm initiation
would be expected with a supercell or two likely, capable of
producing all severe weather hazards. Finally with all of that said,
precipitation present over the region will start to lessen in
coverage and intensity during the mid to late evening hours as
forcing and instability wane. As for temperatures, a warm to hot day
is expected. A cold frontal passage late Friday will help to keep
temperatures from getting too hot, with much of the area hovering
around seasonal values for late June.

Monday - Wednesday: For the first half of the upcoming week, active
weather continues for the area. Messy flow will remain in place as
shortwaves drift over south central and southeastern Colorado in the
overall westerly to southwesterly flow. And while moisture will
remain in place, it is expected to start mixing out more, so
moisture quality will start to drop. With that all said though, the
combination of the waves and moisture will allow for additional days
of afternoon rain showers and thunderstorms across the region,
especially along the mountains, where forcing will be strongest.
Along with that though, a cold front will race southward within the
Tuesday - Wednesday timeframe, and that feature will also help
blossom more rain showers and thunderstorms, particularly across the
eastern plains. Temperatures during this period will hover around
seasonal values for early July. Wednesday is likely to be the
coolest day given the cold front passage Tuesday into Wednesday.

Thursday - Friday: Quieter weather returns during the later half of
the upcoming week. A ridge of high pressure will push in from the
west and sit across the western CONUS, causing northwesterly flow to
prevail over the region. Not only will forcing lessen with this
pattern, but moisture will be scoured out. With weaker forcing and
less moisture, drier conditions are anticipated, though with
isolated showers and thunderstorms still expected along the
mountains each afternoon. Looking at temperatures, the warm to hot
values continue, with near seasonal temperatures expected.
Additional cold fronts may be pushed southward during this
timeframe, and help to cool the area to below seasonal temperatures.

&&

.AVIATION /18Z TAFS THROUGH 18Z SUNDAY/...
Issued at 1135 AM MDT Sat Jun 29 2024

For KCOS and KPUB..VFR conditions are expected for the next few
hours early this afternoon, before showers and thunderstorms begin
to push off the terrain and near or over both stations after 23Z
this afternoon. MVFR conditions during thunderstorms will be
possible, along with gusty and erratic thunderstorm winds from
around 00Z through 06Z this evening. MVFR and IFR ceilings and
visibilities are also expected from 06Z through around 14-16Z
tomorrow morning due to stratus and upslope conditions, and could
persist longer at KCOS.

For KALS..VFR conditions are expected for the next 24 hours, with a
slight chance for vicinity showers and weak thunderstorms this
afternoon, mainly from 23Z until 03Z. Winds are expected to be
mostly light today, but could be gusty and variable near
thunderstorm activity later this evening.

&&

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

&&

$$

SHORT TERM...KT
LONG TERM...SIMCOE
AVIATION...EHR