383
FXUS65 KPUB 131729
AFDPUB

Area Forecast Discussion
National Weather Service Pueblo CO
1129 AM MDT Thu Mar 13 2025

.KEY MESSAGES...

- Breezy southwest winds will bring critical fire weather to
  the eastern plains today into this evening.

- Blowing snow will continue across the mountains through
  Friday morning. Heaviest amounts over the San Juans, Sawatch
  Range, and southern Sangres.

- Strong Spring storm system will push over and eject to the
  northeast throughout Friday.

- Strong,to possibly damaging, winds are expected along and
  east of the eastern Mountains Friday.

- Moderate to heavy wind driven snow is expected along the
  mountains early Friday.

- Drier conditions return Sunday and Monday, with another storm
  system possible by midweek next week.

&&

.UPDATE...
Issued at 1006 AM MDT Thu Mar 13 2025

The high wind watch for the southern Sangres/S I-25 corridor has
been UPGRADED to a high wind Warning. All data sets are
indicating a mtn wave setting up on the east slopes of the
Southern Sangres and this will cause strong damaging winds over
these locations. I would not be all that surprised if winds hit
100 mph on the across the higher terrain of western Las Animas
county. /Hodanish

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 423 AM MDT Thu Mar 13 2025

Today, breezy southwest flow will increase across our region as an
upper-level trough digs down over California. By this afternoon,
these winds will mix down towards the surface, with strong gusts
across most of the area. Over the mountains, areas of blowing snow
will be possible as incoming moisture and supportive orographics
result in accumulating snowfall. The eastern San Juans will get the
heaviest snow, though lighter amounts are expected over the Sawatch
Range and the Sangre de Cristos. For the eastern plains, widespread
critical fire weather conditions are expected through most of the
day, with RH dropping to around 10 percent or so. Finally,
temperatures will be a bit warmer today. Highs over the valleys will
rise into the mid-high 50s, while the eastern plains will range from
the mid-60s closer to the terrain to near-80 at the CO/KS border.

Moving into tonight, gusty winds will stick around just a bit past
sunset as the upper jet maximum pushes south. As such, the Red Flag
Warning goes out through 8pm. Meanwhile, synoptic lift will briefly
increase over the peaks of the Continental Divide as the upper
trough begins to encroach on our area, allowing for continued
moderate-heavy snowfall over some of our mountain peaks. Looking at
total accumulations through Friday morning, the eastern San Juans
still appear to collect the most snow, with 1-2 feet across most of
the higher areas. Meanwhile, the Sawatch Range and parts of the
Sangres, particularly the southern Sangres, could be seeing upwards
of 4-7 inches. Finally, the rest of our mountains will be seeing 1-3
inches, with snow transitioning towards the Pikes Peak Region as the
upper low moves past tomorrow morning. Additionally, as the mid-
level jet max pushes past our region as we move into the long-term
period, winds will quickly increase over the southern Sangres, as
well as adjacent lower areas in Huerfano and western Las Animas
Counties. As such, have started the High Wind Watch at 09Z (3am
Friday morning).

&&

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
Issued at 423 AM MDT Thu Mar 13 2025

Friday: The end of the week will continue to bring active weather as
a strong Spring storm system passes over the area. Synoptically, a
strong and compact wave will push over the area early in the day,
and eject to the northeast during the later part of the day. With
this feature over the area, strong synoptic and orographic forcing
will be in place. In addition, a pocket of Pacific moisture will be
advected over the area with the wave passage. With the increased
forcing and moisture, snow showers are expected to persist across
the mountains and valleys, with moderate to heavy wind driven snow
along the mountains. Along with that, precipitation is anticipated
to develop along the backside of a deepening low pressure system as
a trowal wraps around the system. With that said, this will be a
rather warm system initially, and given that, snow levels will only
fall to around 5,500 ft. This will limit snow to higher elevations
for the plains, such as the Palmer Divide, with all rain below this
level. Along with that, low levels will start off dry despite the
development of a mid level trowal. This will hinder snow or rain
reaching the surface early during this period, with precipitation
reaching the surface by early afternoon as low levels become
sufficiently saturated. With that all said though, as the storm
system ejects to the northeast during the afternoon, precipitation
coverage and intensity will lessen, with any remaining showers
becoming restricted to the mountains where orographic forcing will
persist. In addition to all of that, and as alluded to, a strong low
pressure system will rapidly develop and deepen in response to the
base of the wave and the left exit region on the associated jet
streak swinging over. As this low develops and deepens, winds will
increase in response to this, with the strongest winds along and
east of the eastern mountains. Many of the plains are expected to
experience wind gusts of 50-55 mph, with gusts up to around 60 mph
possible. The strongest winds however may develop along the southern
Sangre de Cristo Mountains, and adjacent Huerfano and Las Animas
Counties. Latest high-res ensemble and deterministic model guidance
show a period of strong reverse shear, along with a mountain top
inversion, materializing during the morning hours. These factors,
along with the simple "vacuum" like effect of a rapidly deepening
low pressure system, will allow for rather strong winds to develop
Friday morning, with winds gusting upwards to around 85 mph along
the southern Sangres and upwards of around 75 mph for portions of
Huerfano and western Las Animas Counties. With strong agreement
between guidance, and a rather clear signal even in ensemble
guidance, confidence has increased for this scenario, with medium to
high (60-70%) confidence in these strong winds, and as such, a High
Wind Watch has been added for these localized areas. As the low and
parent wave push to the northeast during the later half of the day,
winds will steadily lessen during the afternoon, though will remain
breezy, with relatively lighter winds returning Friday night. Beyond
all of that, cloudy skies early will slowly given way to partly
cloudy skies late, with a mild temperature day. Speaking of
temperatures, despite the storm system passing over, much of the
area will remain relatively warm, with many areas staying around
seasonal values for mid March.

Saturday: For the start of the weekend, a slight downtick in active
weather is expected, though mountain snow continues. The broader
troughing pattern that brought the Thursday - Friday storm system
will continue to trek eastward. While it does so, another shortwave
will become absorbed into the broader trough and swung southward
along the western periphery of the troughing. This will bring
another period of heightened forcing, especially along the
mountains. Given this, snow showers will uptick in coverage Saturday
as these features push over. Along with that, a shower being shoved
across the valleys and immediate I-25 corridor can not be ruled out.
With that all said, as the broader troughing and absorbed wave exit
the area late Saturday, and ridging starts to develop behind it, any
precipitation present is anticipated to dissipate, with dry
conditions prevailing by Sunday morning. Outside of all of that,
another cloudy day is expected, with breezy winds for many. Looking
at temperatures, colder air will finally filter into the region,
with much of south central and southeastern Colorado dropping to
below seasonal values.

Sunday - Monday: For the end of the weekend and start of next week,
quiet weather returns for south central and southeastern Colorado.
As previously mentioned, a ridge of high pressure will build in
behind the busy Spring storm system Saturday night and remain in
place through Monday. Given greater subsidence with this pattern,
dry conditions are anticipated for area. Otherwise, gusty winds are
expected both days, but especially Monday, with occasional pockets
of mid to high level clouds. Temperatures during this period will
start to warm substantially in response to downsloping winds
materializing, with Monday being the warmest of the two days.

Tuesday - Wednesday: Heading into the midweek timeframe of next
week, active weather makes a return. Another troughing pattern is
expected to develop and push over the region during this period.
Ensemble model guidance are in decent agreement on this feature
impacting the area, leading to medium to high (60-70%) confidence in
this pattern evolution. With this troughing in place, precipitation
chances will become heightened for much of the region, but
especially along the mountains where forcing will be greatest. In
addition, clouds would be expected to increase, with breezy
conditions developing for much of the area. As for temperatures,
given the unsettled pattern, temperatures are expected to drop back
to around and below seasonal values, especially on Wednesday.

&&

.AVIATION /18Z TAFS THROUGH 18Z FRIDAY/...
Issued at 1125 AM MDT Thu Mar 13 2025

Main concern during the next 24 hours will be the winds. A
powerful Pacific storm will blast across the region tonight. A
strong boundary will push across the region roughly prior to
sunrise and we will see a strong windshift with it. Not much
precip, if any, is expected at KCOS or KPUB, but KALS could see
some snow squalls during the early AM hours. Overall, gusty
southwest winds will occur this afternoon into the evening
hours, and then shift to the northwest and will be stronger
tomorrow after sunrise.

&&

.PUB WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory from 6 PM this evening to noon MDT
Friday for COZ060.
Winter Storm Warning until noon MDT Friday for COZ068.
Winter Weather Advisory from 9 PM this evening to noon MDT
Friday for COZ074-075.
High Wind Warning from midnight tonight to 3 PM MDT Friday for
COZ074-075-087-088.
Red Flag Warning until 8 PM MDT this evening for COZ227>237.
High Wind Watch from Friday morning through Friday evening for
COZ094>099.

&&

$$

UPDATE...HODANISH/PETERSEN
SHORT TERM...GARBEROGLIO
LONG TERM...SIMCOE
AVIATION...HODANISH