000
FXUS65 KPUB 280942
AFDPUB

Area Forecast Discussion
National Weather Service Pueblo CO
342 AM MDT Sun Apr 28 2024

.KEY MESSAGES...

- Lingering snow showers will continue over the mountains and
  higher terrain of Teller and El Paso County this morning.
  Patchy freezing fog is possible for portions of the Palmer
  Divide.

- Showers/high elevation snow showers, and a few thunderstorms,
  will develop later in the day over the higher terrain and then
  move out over the plains during the evening. There is low
  confidence (less than 30 percent) that some of these
  showers/storms may produce flash flooding for burn scar and
  urbanized areas.

- Warming trend through midweek.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 341 AM MDT Sun Apr 28 2024

Today...

The major shortwave will continue to progress towards the east. The
associated surface low pressure is located to the northeast this
morning, with some wrap-around moisture providing lingering snow
showers over the higher terrain of Teller and El Paso counties. With
low-level moisture in place, there could also be some isolated areas
of freezing fog creeping over parts of the Palmer Divide during the
early morning hours, which could create some slick road conditions
if this occurs. These light snow showers will continue to taper off
throughout the morning hours as the surface low pulls away. There is
also going to be some snow continuing over the higher terrain due to
an upper level low on the backside of the major shortwave trough
that is currently located over Four Corners area. By later in the
day, this will begin to progress eastward and provide the
instability, along with residual moisture and orographic lifting to
trigger some development of showers and a few thunderstorms by later
in the afternoon.

Given that the mid-level flow will be primarily out of the west and
the progression of the upper level low towards the east will allow
for the convection to move off the mountains and over into the
plains towards the evening hours. With this, there could be some
additional snow accumulations for the higher elevations. CAPE values
are not that impressive, so these should remain more of your garden
variety type thunderstorms with little confidence that anything will
become strong. The biggest threat if this does occur will be some
gusty outflow winds to possibly 50 mph, and hail of up to half inch
in size. Given where the position of the upper level low will be,
the best chance of a thunderstorm becoming stronger would be over
the southern Sangre de Cristo Mountains, Wet Mountains, and over the
adjacent plains in the Walsenburg area, where the slightly better
CAPE (of nearly 1000 J/kg) will be. That being said, there is low
confidence (less than 30 percent) that some of these heavier showers
and/or thunderstorms could put down a good amount of rain in a short
period of time and result in flash flooding, especially for the burn
scar and urbanized areas.

With northwesterly flow still in place over the region, temperature
will still be on the cooler side, with highs topping out in the
upper 50s to mid 60s for most of the plains, to the 50s for the
upper Arkansas River Valley and San Luis Valley. It will be
generally in the 30s and 40s across the higher terrain, although the
highest peaks will likely only max out in the 20s.

Tonight...

Showers and storms during the evening hours over the eastern plains
will continue to dissipate and move towards the east and out of the
CWA by early in the morning hours of Monday, mainly over the far
southeastern plains, Baca County in particular. Otherwise, as high
pressure begins to build back in, skies will begin to clear for most
locations going through the night. With the cooler air in place,
temperatures will drop into the 30s for most locations across the
plains, with lows falling into the teens and 20s for high country.
-Stewey

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...
Issued at 341 AM MDT Sun Apr 28 2024

Monday and Tuesday...Increasing westerly flow aloft across the
region will usher in mainly dry and much warmer conditions to start
the work week. Long range models are indicating a slight upper
disturbance crossing the Rocky Mt region on Tue, but right now it
likes like the main effects from this feature will remain across the
northern half of CO. Save for some isolated shower activity across
the higher elevations of Lake County, plan on dry conditions with
highs on Mon in the 60s for the high valleys and upper 60s to upper
70s for the plains. On Tue it really starts heating up, with highs
in the mid 60s to lower 70s for the high valleys, and mid 70s to mid
80s for the plains. Spotty critical fire weather conditions return
to the San Luis Valley on Tue.

Wednesday...A stronger upper low pressure system crosses the Rockies
on Wed, producing increased west-southwest flow across the
state as well as pushing a cold front south across the forecast
area during the afternoon. Current forecast trend is for another
very warm day across the area before the front arrives, and
with the stronger surface winds high fire danger will be likely
for the San Luis Valley and along the southern border. Once the
front pushes south across the Palmer Divide some time in the
afternoon, isolated to scattered showers and thunderstorms will
spread across the eastern plains. Maximum temps are expected to
climb into the 60s to around 70F for the high valleys, and 70s
to mid 80s for the plains.

Thursday and Friday...Upper system exits the region on Thu, with
cooler northwest flow aloft settling in to end the work week. Post-
frontal conditions across the eastern plains will make for
widespread precip chances on Thu, then gradually diminishing
activity through Fri. Plan on cooler temps both days, with highs on
Fri in the mid 50s to mid 60s for most locations on Thu, then 60s
across the high valleys and 60s to around 70F for the plains on Fri.

Saturday...Low confidence at this time on the forecast for the
weekend, though long range models point to Colorado being under
generally weak westerly flow aloft, as another low pressure system
takes shape just off the West Coast. Temps will warm 5 to 10 degrees
above the previous days. Moore

&&

.AVIATION /12Z TAFS THROUGH 12Z MONDAY/...
Issued at 341 AM MDT Sun Apr 28 2024

VFR conditions are expected to prevail for all TAF sites (KALS,
KCOS, and KPUB) throughout the forecast period, however, this
morning there will be some low CIGs for all stations which will
result in MVFR, and possible IFR criteria before 15Z, then cloud
decks are expected to lift. There is very low confidence (less than
20 percent) of VCSH this morning for KCOS. By later in the day, VCSH
and/or VCTS will come back into the picture for all stations,
although it is still questionable as to whether or not these come on
station, given that these showers will be more isolated in nature.
If SHRA/TSRA does develop, it could temporarily reduce CIGs and VIS
to MVFR/IFR criteria. It could also result in periodic windshifts
and increased wind speeds for all terminals. With lower levels
becoming more stable, winds will be light (less than 10 kts) and
predominantly influence by diurnal effects at all terminals.
-Stewey

&&

.PUB WATCHES/WARNINGS/ADVISORIES...
Winter Storm Warning until 6 AM MDT early this morning for
COZ058-060-081-082.
Winter Weather Advisory until 6 AM MDT early this morning for
COZ059-061-063-066-068-073-076.

&&

$$

SHORT TERM...STEWARD
LONG TERM...MOORE
AVIATION...STEWARD

NWS PUB Office Area Forecast Discussion