411
FXUS65 KPUB 221730
AFDPUB

Area Forecast Discussion
National Weather Service Pueblo CO
1030 AM MST Fri Nov 22 2024

.KEY MESSAGES...

- Dry weather continues in the short term.

- Warmer and drier conditions will persist through Saturday.

- Snow will begin over Continental Divide on Sunday morning and
  spread eastward over higher terrain throughout the day and
  into Monday.

- Snow over the higher terrain will begin to pick up in
  intensity Tuesday night through Thursday.

- Some showers will be possible for portions of the plains on
  Monday and Tuesday, then with increasing chances going into
  Wednesday and Thursday.

- Temperatures will be on a cooling trend from Sunday and onward
  through the end of the work week, with values well below
  average by Thursday.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 331 AM MST Fri Nov 22 2024

Currently...Broad ridge of high pressure across the southern US was
produced somewhat brisk westerly flow aloft across Colorado this
morning, which was producing some mountain wave clouds across the
northern half of the state. Much of the forecast area remained
mostly clear, and temperatures as of 2 AM had cooled into the teens
for the San Luis Valley, 30s to mid 40s for most other locations,
and 20s along the Arkansas River from Pueblo east to the Kansas
border.

Today and Tonight...The upper level ridge will continue to be the
main influence across the region through the short term, with warmer
temperatures and generally lighter winds expected today. Mt wave
clouds to the north could dip further south during the day today,
affecting the central mts and the Pikes Peak region, but for the
most part plan on plenty of sun for most locations. As a large
trough of low pressure along the West Coast starts to deepen, the
flow aloft will start to increase and start shifting to a more
southwest direction across the Four Corners. This will likely help
keep those locations along the eastern slopes of the southern mts a
bit warmer tonight into Sat morning.

Plan on highs today in the 40s for the San Luis Valley, 50s for the
Upper Arkansas River Valley, and lower 50s to mid 60s for the
plains. Overnight low temps tonight are forecast to cool in to the
10 to 20 degree range for the San Luis Valley though Alamosa may dip
down into the single digits, 20s for the Upper Arkansas River
Valley, and 20s to mid 30s for the plains. Moore

&&

.LONG TERM /SATURDAY THROUGH THURSDAY/...
Issued at 331 AM MST Fri Nov 22 2024

Saturday...

Ridging over the region will begin to flatten Saturday in wake of an
approaching longwave trough upstream. Winds will begin to increase
out of the west-southwest, especially by tomorrow night. With
downsloping winds, it will be quite warm for the lower elevations,
although still relatively cooler for portions of the plains where
there is still a snowpack present. Highs will be getting up into the
60s for much of the plains, although it will still be in the 50s
where there is a snowpack still in place. There will also be some
gap flow winds in the vicinity of Canon City and Walsenburg, during
the afternoon hours on Saturday as a trough upstream begins to
approach the region. With lower RH values, the meteorological
conditions will meet critical fire weather criteria for western
Huerfano County and eastern Fremont County, although fuels are not
yet critical in these areas for there to be any fire weather
concerns.

Sunday through Thursday...

Deterministic models are continuing to align better and resolve the
longwave pattern evolving this weekend and into next week, which has
a trough over the western states further flattening as it moves
inland and over the inner mountain west. As a major shortwave trough
begins to move over the region on Sunday, there will be snow showers
beginning over the ContDvd early Sunday, which will be spreading
over the rest of the higher terrain by later in the day. As 700 mb
winds are enhanced by a finger of the jet moving in over Colorado
occurs later on Saturday night and through Sunday, there will be
increasing winds across the higher elevations and some locations.
High res model guidance, and especially the NAMNest suggest that a
few locations, such as the southern Sangre de Cristo Mountains,
could have winds gusts approaching High Wind Criteria through the
mid part of the day on Sunday. There will also be an associated cold
frontal boundary moving down from the north on Sunday night which
will allow for temperatures to be cooler on Monday. Some of these
showers will spill over into the adjacent valleys and plains,
although with the rainshadow effect as westerly flow in the mid
levels becomes more pronounced, it is more likely that a majority of
these showers will be in the form of virga.

There will be more or less a break in the snow activity moving in
over the higher terrain on Tuesday, but then a much more broad
shortwave trough will begin to move in by later in the night of
Tuesday and into Wednesday, with an increase in intensity of
snowfall for the Continental Divide as it does. The deterministic
models begin to diverge a little more with regards to the
progression of the trough by Wednesday, with the slightly quicker
propagation eastward with the ECMWF, vs the GFS and Canadian. A
deepening of the trough going into Wednesday and another front
dropping south will help to increase chances of precip for the
plains and help to also reinforce some colder air with highs in the
30s for the plains on Thursday. Snow will continue to taper off by
later in the day as the low pressure begins to pull away from the
region. The ContDvd, mainly the central and southwestern mountains,
still look to have the highest anticipated total snowfall amounts
throughout this event in its entirety, with some locations within
the Sawatch Range and eastern San Juan Mountains possibly getting
around 2 feet of snow (and locally higher amounts possible) through
the course of the 5 day period.   -Stewey

&&

.AVIATION /18Z TAFS THROUGH 18Z SATURDAY/...
Issued at 1026 AM MST Fri Nov 22 2024

VFR conditions expected at all three TAF sites, KCOS, KALS, and
KPUB through the forecast period. Winds will be light and
diurnally driven, generally under 10kts. Higher elevations
could see gusts between 20-25 kts. -Clouse

&&

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

&&

$$

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