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fxus65 kpub 202131 

Area forecast discussion
National Weather Service Pueblo Colorado
331 PM MDT sun Oct 20 2019

Short term...(this evening through monday)
issued at 329 PM MDT sun Oct 20 2019

Currently, GOES water vapor imagery shows an impressive closed upper
low moving east across the NE/South Dakota border, with trailing energy back
over Colorado. Upper air analysis reveals a strong jet upstream of
the broader trough poking it's exit region southeast into the Great
Basin. Light snow showers continue over the central mountains and in
Leadville as a result of increasing large scale forcing over central
Colorado in the approaching left jet exit region, and favorable
orographics. The rest of the forecast area is dry with below normal
tpw, but very windy. Winds are gusting over 40 mph over large swaths
of southern Colorado, and combined with very low rh, is causing red
flag conditions everywhere but the Continental Divide. Temperatures
are around 60 over the plains, 50 in Colorado Springs, and 30s to
40s in the high valleys.

Tonight and tomorrow, the aforementioned trough will continue east
across the plains and into the Midwest, while the strong upper jet
shifts east. Increased large scale forcing in the left jet exit
region along with still favorable orographics over northern portions
of the central mountains will lead to an uptick in snowfall late
tonight into tomorrow. Total additional accumulations of 2-5 inches
are expected, primarily over higher elevations of Lake County. The
additional snow accumulations, combined with gusty winds and
resulting blowing snow, prompted the issuance of a Winter Weather
Advisory for 06z tonight through 03z late tomorrow night. The rest
of the forecast area is expected to remain dry.

Winds will continue to gust over 40 mph over much of southern
Colorado into early this evening, weakening after dark. Overnight
lows will be in the upper 20s across the eastern plains and Colorado
Springs, and teens to 20s in the high valleys. Tomorrow, winds will
increase again out of the northwest during the morning, gusting as
high as 35 mph during the morning and afternoon across the lower
elevations, and up to 55 mph over the mountains. Temperatures will
remain cool, with highs around 60 across the plains, near 50 in
Colorado Springs, and 40s in the high valleys. The cool temperatures
and moistening low levels will prevent widespread critical fire
danger. The exception will be over Huerfano, Las Animas, and Otero
counties, where drier surface conditions will combine with the gusty
winds to cause a period of red flag conditions during the afternoon.
Therefore, a red flag warning has been issued for those areas for
noon to 7 PM. Other low elevation areas will be near critical, so
fire precautions should be taken.

Long term...(monday night through sunday)
issued at 329 PM MDT sun Oct 20 2019

Moderate northwest flow aloft will continue over the area thru Tue
night, with occasional snow showers over the sawatch and mosquito
mtns. Temps will be a bit warmer on Tue, with highs being around
average. Highs across the plains should be in the 60s, with mid 50s
to around 60 in the high valleys.

Wed, an upper trof will be dropping south out of Montana into WY, and
pushing a front through eastern Colorado in the afternoon. The GFS keeps
most of the precip associated with this system to the north of the
area thru the afternoon, with just some snow moving into the sawatch
and mosquito mtns. While the ec brings precip chances along the
eastern mtns and I-25 corridor in the late afternoon. High temps on
Wed depend on the timing of the front.

Wed night, the upper trof moves over Colorado but there are differences in
the models as to exactly where it will track. The ec drops an upper
low into southwest co, and brings precip to all of southern co, with
relatively high quantitative precipitation forecast over the eastern mtns and I-25 corridor. The GFS
is more of a progressive system that is centered farther east than
the ec, and it brings precip mostly over the central mtns, eastern
mtns and I-25 corridor, with lower quantitative precipitation forecast.

On Thu, the ec upper low moves into north central nm by midday and
then into east central nm in the evening. This scenario keeps
precip over all of southern Colorado thru midday, and then decreases
precip chances from north to south thru the afternoon, with only
some light showers in locations near the southern Colorado border. The
GFS solution moves the upper trof east, with some light precip along
the eastern mtns and I-25 corridor in the morning, and then very
little, if any precip in the afternoon. Temps on Thu will be much

Dry weather returns for Fri and Sat. High temps Fri will be warmer
than Thu, but below average, while temps on Sat should be about
average in the high valleys and above average over the southeast
plains. A front is then expected to move thru the area on sun,
bringing another cool down.&&

Aviation...(for the 00z tafs through 00z Monday evening)
issued at 329 PM MDT sun Oct 20 2019

VFR and dry conditions are expected at the three taf sites (kals,
kcos, kpub) over the next 24 hours. West to northwest winds gusting
as high as 45 knots at the three taf sites will continue early this
evening. Winds will decrease to less than 15 knots this evening,
before gusting again starting late tomorrow morning to around 30


Pub watches/warnings/advisories...
red flag warning until 8 PM MDT this evening for coz222-224>237.

Red flag warning from noon to 7 PM MDT Monday for coz229-230-232-

Winter Weather Advisory from midnight tonight to 9 PM MDT Monday
for coz058-060.



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