927
FXUS65 KPUB 052331
AFDPUB

Area Forecast Discussion
National Weather Service Pueblo CO
531 PM MDT Wed Jun 5 2024

.KEY MESSAGES...

- A tad cooler tomorrow across southeast Colorado with a few
  afternoon showers and storms possible across the higher terrain.

- Wet conditions beginning Friday and lasting into Monday could
  bring localized flooding concerns to southern Colorado.

- A few strong to severe storms may be possible on the Plains
  Friday and again Saturday.

&&

.SHORT TERM /THROUGH THURSDAY/...
Issued at 239 PM MDT Wed Jun 5 2024

Subsidence under the building ridge evident across south central
Colorado, with the only clouds on satellite being some CU along
a moisture boundary across eastern Las Animas and Baca counties,
as well as some CU across the northern mountains and the northeast
Colorado Plains, associated with a passing wave across the northern
Rockies. Warming aloft along with the sunny skies has allowed
temperatures to warm into the mid 80s to mid 90s across the Plains
at this time, with current readings in the 60s to lower 80s across
the high mountain valleys and the higher terrain.

For Tonight and Thursday...The northern Rockies passing wave sends a
weak northerly surge across eastern Colorado later this evening, with
easterly low level upslope progged to develop across the southeast
Colorado Plains later tomorrow morning and into the afternoon. This
will lead to a slight increase in available moisture, with latest model
data indicating some modest cape across the lower eastern slopes by
tomorrow afternoon. This will allow for some cu buildups and a few
possible -shra and maybe even an isolated -tsra over and near the higher
terrain tomorrow afternoon. Any storm that can develop will be high based,
producing more wind than rain. With the upslope flow, high temperatures
across the plains will be slightly cooler than today, though likely still
in the 80s to lower 90s, with highs across south central Colorado at or
slightly warmer than today`s values. As for lows tonight, I did lower
current NBM values some, especially across the high mountains valleys,
where radiational cooling will be maximized.

&&

.LONG TERM /THURSDAY NIGHT THROUGH WEDNESDAY/...
Issued at 239 PM MDT Wed Jun 5 2024

There is overall model agreement and reduced ensemble spreads
through Monday, with differences showing up for early to mid
next week.  Increasing moisture on Friday will lead to widespread
showers and thunderstorms beginning Friday, and remaining in
the forecast through Monday. The primary concern will be the
potential for heavy rainfall along the Eastern Mountains, out
into the Plains. With this shower and thunderstorm activity will
come relief from the hot temperatures. Beyond Monday, much
uncertainty exists with the overall pattern evolution, but most
guidance points towards drier conditions.

Thursday night and Friday...a weak upper wave embedded in the
northwest flow will likely spark a few showers and thunderstorms
across the Palmer Divide, and slide them southeast across the
Plains, remaining north of Highway 50 late Thursday night into
Friday morning. This will likely produce areas of light, spotty
rain during the overnight hours. One last hot day is expected on
Friday, with highs across the region in the 80s to pushing 100
degrees on the Plains. Increased moisture and energy moving
across Colorado will lead to shower and thunderstorm development
by Friday afternoon, initiating over the Mountains. This
activity will shift east into the Plains Friday evening,
clearing to the east by Saturday morning. There is a low risk of
a few strong to severe storms Friday late afternoon and evening
over our northeast zones (Kiowa, Bent and Prowers Counties).
The main threats may be wind and large hail.

Saturday into Monday...the upper ridge is forecast to build across
the Great Basin over the weekend, while upper troughing drops
south out of Canada into the Great Lakes. The main model
difference over the weekend is the track of the Canadian system.
The GFS is further east, dropping the low into the Great Lakes,
while the ECMWF is further west. All model solutions drop a
cold front across the Plains Saturday morning, further
increasing moisture across the Plains, and turning low level
flow upslope easterly. Expect showers and thunderstorms to
develop by midday and spread eastward into the I-25 corridor
through the afternoon and evening. A few strong to severe storms
may be possible given the shear profile and expected
instability. Large hail and gusty winds would be the primary
concerns. Continued moist, upslope flow is expected on Sunday
across all of southern Colorado. Widespread showers and
thunderstorms are forecast to develop by Sunday afternoon and
evening. These storms will likely be efficient precipitation
producers, and local flooding possible, especially for areas
that see heavy rain on Saturday. The severe threat looks less on
Sunday, with SBCAPE values only around 500 j/kg. There could
still be small hail and gusty winds to accompany the heavy
rainfall. Monday looks similar to Sunday, with another round of
showers and thunderstorms, initially developing over the
Mountains, and spreading east into the Plains. Once again,
localized flooding may be a concern with areas that see several
days of heavy rainfall. Overall, temperatures will be much
cooler over the weekend into Monday, with most areas in the 70s
to lower 80s across the region.

Tuesday into Wednesday...model guidance and ensemble spreads
increase by mid week, but all point to drier conditions as high
pressure looks to build out west. Afternoon highs will also be
on the rise, with 70s to upper 80s to near 90 by Wednesday.
Shower and thunderstorm activity should also become more
isolated to scattered in nature. Mozley

&&

.AVIATION /00Z TAFS THROUGH 00Z FRIDAY/...
Issued at 529 PM MDT Wed Jun 5 2024

VFR conditions are expected to prevail for all TAF sites (KALS,
KCOS, and KPUB) throughout the forecast period. Winds will be mainly
diurnally influenced at all terminals, and will increase and
become gusty out of the SSW at KALS, SSE at KCOS, and SE at
KPUB, towards the end of the forecast period. -Stewey

&&

.HYDROLOGY...
Issued at 239 PM MDT Wed Jun 5 2024

Recent warm temperatures are producing rapid snowmelt over the
higher terrain along the upper reaches of the Arkansas River, from
the headwaters near Leadville, down to near Canon City.  Water
levels and flows are forecast to increase over the coming days.  At
this time, river levels are expected to remain below flood stage,
however, swift flows and cold water temperatures will be dangerous.
Stay away from fast flowing water!

Periods of heavy rainfall are expected Saturday through Monday,
mainly over the Eastern Mountains, down into the I-25 corridor.
This could lead to localized flash flooding, especially on area
burn scars, and urban areas. This heavy rainfall, along with
localized snow melt could also lead to rises on area streams and
rivers.  Mozley

&&

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

&&

$$

SHORT TERM...MW
LONG TERM...MOZLEY
AVIATION...STEWARD
HYDROLOGY...MOZLEY