987
FXUS65 KPUB 071113
AFDPUB

Area Forecast Discussion
National Weather Service Pueblo CO
413 AM MST Thu Nov 7 2024

.KEY MESSAGES...

- A band of moderate to heavy snow to move south to north across
  the region through the day, with the greatest snow
  accumulations expected across the SE Mtns into the southern
  I-25 Corridor.

- Another brief lull in precipitation late this afternoon and
  evening, especially north of Highway 50, with precipitation
  increasing in coverage from south to north later Thursday night.

- Periods of heavy snow will continue across the Eastern
  Mountains, east across the Plains Friday through Saturday.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 344 AM MST Thu Nov 7 2024

Current water vapor imagery and upper air analysis has moderate
southerly flow aloft across the region with an upper low spinning
across east central Arizona. Water vapor and IR imagery is also
indicating impressive uvv, along with regional radars indicating
blossoming precipitation across the southern Rockies into southern
Colorado, as an embedded shortwave is rounding the base of the low
across central New Mexico at this time. The southerly flow aloft is
also spreading abundant moisture across the region, with GOES
Blended Total Water Vapor imagery also indicating PWATS of 150-200
percent of normal across the Southern and Central Rockies at this
time.

Models remain in fairly good agreement of the upper low to continue
into southwestern New Mexico this afternoon, before lifting out
into south central New Mexico later tonight. Movement of this
system will rotate a band of moderate to heavy snow across southern
Colorado through the morning, with light to moderate precipitation
continuing through the afternoon into the evening, with continued
waa within the moderate southerly flow aloft. Current temperatures
in the 20s to lower 30s across the region to support accumulations
of 3 to 6 inches across the Eastern Mtns and into the I-25 Corridor
through the morning, with strong diabatic cooling leading to the
potential for similar accumulations across the far southeast plains
this morning. 1 to 3 inches of snow will also be possible across the
southwest mtns into the San Luis and mid and upper Arkansas valleys.
Continued light to moderate waa snowfall could bring another 1 to 3
inches areawide this afternoon, with the greatest amounts expected
across the SE Mtns and southern I-25 Corridor. With the clouds and
expected precipitation, should not see much variation in temperatures
today, with highs in the 20s to lower 30s, warmest across the
Arkansas River Valley.

While light to moderate snowfall continues late this afternoon
and evening, the next band of moderate to heavy snowfall looks to
lift out across the Raton Mesa and the far southeast Plains into
early Friday morning. This could bring another 3 to 6 inches of
snow to the SE Mtns and southern I-25 Corridor overnight, with
with a snow to rain transition possible across the southeast
plains, as latest model data is supporting snow levels rising and
dew pts increasing into the mid 30s across the far southeast
plains. Will need to watch if this snow to rain transition does
indeed happen, as if not, there will be more snow accumulation
than is current forecasted across the far southeast Plains.

&&

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
Issued at 344 AM MST Thu Nov 7 2024

Models are all in agreement with the ejection of the upper low
out of New Mexico, northeast into the Central Plains through
Saturday. Beyond Saturday, drier conditions look to return to
southern Colorado, with the exception of a shortwave trough
passing across the Rockies Tuesday into Wednesday next week.
There is uncertainty with this shortwave in strength, and there
has been little run to run consistency, so confidence in impacts
with this system are low.

Friday through Saturday...no change to the forecast thinking,
with the upper low tracking across central New Mexico Friday,
and lifting northeast along the Colorado-Kansas border Saturday,
and finally into central Nebraska Saturday night. All the
ingredients continue to be in place for heavy precipitation
across out Eastern Plains. A prolonged period of deep upslope
flow (easterly at 700 mb at 30+ kts), deep moisture wrapping
around the upper low, isentropic lift, and peak vertical motions
will lead to the widespread heavy precipitation. Temperatures
remain a big question mark near the Kansas border. Warm air
advection there will keep temperatures in the mid 30s Friday and
Saturday, likely keeping precipitation type as rain and
limiting snowfall amounts. Overnight periods near the Kansas
border will fall below freezing and allow for the switch over to
snow. There are a couple of caveats...one being precipitation
intensity which may bring snow levels down, and if this system
is a couple degrees colder. At this time, the going Winter
Weather Advisories look good, but we will continue to monitor
eastern Kiowa and Prowers Counties for snow potential.

For the Eastern Mountains into the rest of the Plains, Winter
Storm Warnings are in effect. Models continue to peg the
southern Sangre de Cristo and Met Mountains, east into the
southern I-25 corridor. These areas will see 1 to 3 feet of
snow, with locally higher amounts possible. Further north,
lesser amounts are expected along the Arkansas River Valley, but
the potential for more is certainly there. Much will depend on
temperatures as well. Currently have low 30s in the forecast,
and that could play a role in snow ratios. Again, if this system
trends slightly colder, snow totals may need to be increased.
Areas over the Palmer Divide will see periods of heavy snow,
with the period on Friday night having the heaviest snowfall.
This has to do with a lobe of energy backing west around the
upper low as it moves north along the Colorado-Kansas border.

Easterly flow looks to move into the San Luis Valley, helping to
increase snow potential for the western edge of the valley.
Winter Weather Advisories look good across the valley.

Snow looks to wind down from south to north Saturday morning as
the upper low departs to the northeast. Flow will shift from
northeaster to northwesterly effectively cutting off
precipitation potential by Saturday afternoon to evening.

For the period Friday through Saturday, travel across the Plains
and Eastern Mountains will likely be very dangerous, if not
impossible. Those with travel plans should prepare by packing an
emergency kit and letting people know where you are traveling
to. Be prepared for these dangerous conditions!

For snowfall potential, see the winter weather highlights
currently in effect.

Sunday through Wednesday...flat zonal flow to weak ridging will
spread across Colorado with drier and warmer conditions.
Afternoon highs into early next week will be challenging due to
any snow cover limiting potential daytime heating. Did not stray
from the NBM guidance with forecast temperatures at this time.
A quick moving upper shortwave is forecast to move across
Colorado Tuesday into Wednesday. This will bring elevated winds
to the region, along with the potential for more mountains
snowfall.  Mozley

&&

.AVIATION /06Z TAFS THROUGH 06Z FRIDAY/...
Issued at 344 AM MST Thu Nov 7 2024

IFR/MVFR conditions are expected at COS, PUB and ALS throughout
the forecast period due to rounds of SN/BR and possible LIFR
criteria due to FG at times. Conditions are expected to meander
between IFR and MVFR, but will also occasionally be down to
LIFR criteria in more moderate to heavier snow showers, and
occasional fog, with the lowest criteria most likely during the
morning hours, between 12 and 18Z. Winds will be synoptically
influenced throughout the forecast period at all terminals, remaining
mostly out of the NW to NE. Winds will weaken towards the end of
the forecast period.

&&

.PUB WATCHES/WARNINGS/ADVISORIES...
Winter Weather Advisory until 5 AM MST Saturday for COZ065>071-
096-098.
Winter Storm Warning until 5 AM MST Saturday for COZ072>089-
093>095-097-099.

&&

$$

SHORT TERM...MW
LONG TERM...MOZLEY
AVIATION...MW