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Area forecast discussion 
National Weather Service Pueblo Colorado
410 am MDT sun Apr 20 2014

Short term...(today and tonight)
issued at 410 am MDT sun Apr 20 2014

..April showers...

Upper low spinning over Raton vicinity this hour...expected to
slowly meander east/northeastward across southeast Colorado today.
Models have been pretty hot on the quantitative precipitation forecast bullseyes last couple days.
So far...these heavy bullseyes have not really materialized.
Convective switches in the models have flipped...but surface air so
far has not been supportive...with surface dews only in the 30s or
less.

This morning...surface dews have been creeping up...east of the
mountains anyway...with values now generally in the lower to middle
40s. This is better than yesterday...and will probably lead to more
efficient precipitation processes today.

Models...NAM...GFS...ECMWF and hi res models...all indicate bands of
convection will develop and rotate into area...wrapping counter-
clockwise around upper low center over southeast Colorado today. We
have seen a little of this this morning...with a slight increasing
trend noted recently...especially across Las Animas County. This
trend should continue through the morning...and then become more
widespread and intense once it is combined with daytime heating
later in the morning through the afternoon into the evening. With
the higher dewpoints working into the area...would suspect more rain
actually reaching the ground today over a broader area. Primary
target looks to be the eastern mountains and plains...with much more
isolated activity over the western mountains and valleys.

Although not great...there will be the chance that some of this
convection could hit a burn scar and cause some minor runoff issues.
Will have to monitor for this through the day. The East Peak fire
scar...southeast of La Veta...as seen some cells train over it
already this morning...with mostly light but sometimes even moderate
intensity showers. Surface observation...though...indicate dews only around
40...with temperatures likely very similar if it is raining...so don't
think rainfall is extreme enough to cause any problems this morning.
But...soils are moistening across the East Peak scar...which will
just make it easier for runoff problems later today should it get
hit again.

Suspect any accumulating snowfall with this system will remain above
10000 feet...as airmass remains pretty mild. A few inches of wet
snow possible above 1ok under the heavier showers...especially
across the southern sangre Delaware cristo and Spanish Peak areas...closet
to the passing upper low center. This is one of the areas that
needs snowfall the most in southern Colorado...so good to have the
moisture down there.

Everything should wind down during the evening as the upper low
pulls east of the area. High pressure will build back in over
area by Monday morning. Lw

Long term...(monday through saturday)
issued at 410 am MDT sun Apr 20 2014

Monday and Tuesday...models are in very good agreement for the start
of the work week. Shortwave ridging on both Monday and Tuesday is expected
to keep warm conditions in place...with isolated convection mainly
tied to the higher terrain both afternoons. Look for maximum temperatures in
the 60s and 70s for Monday...then as SW flow aloft increases on Tuesday
ahead of the next system maximum temperatures are forecast to bump up by 10
degrees into the 70s to lower 80s.

Wednesday and Thursday...ec and GFS models are now indicating a more
northern track for the incoming low pressure system...though there is
still plenty of time for path variance. This will translate to an
increase in probability of precipitation for the County Warning Area...mainly the mts...for Wednesday with the
initial wave. Lingering showers for the central mts are possible
through early Thursday morning as the secondary lobe of energy rotates
around the trailing edge of the system. Currently...precipitation amounts and
chances are not looking significant...but the real concern is on Wednesday
as the pressure gradient tightens and the system passes to the north.
Maximum temperatures in the 70s and 80s combined with strengthening winds could
produce critical fire weather conditions Wednesday afternoon...and this
potential will have to be monitored over the next few days. Thursday afternoon
all precipitation should be done...with slightly cooler maximum temperatures in the 60s
to around 70 f.

Friday and Saturday...shortwave ridging Ushers in the next weekend
with dry conditions and maximum temperatures in the 70s to around 80 f
expected. Moore

&&

Aviation...(for the 12z tafs through 12z Monday morning)
issued at 410 am MDT sun Apr 20 2014

Mild Spring storm system will track slowly east across the flight
area today...bringing showers and a few thunderstorms to the
area...with snow showers above 10000 feet. Despite the clouds and
showers around the area...flight conditions will mostly remain VFR.
However...flight conditions will drop through MVFR/IFR and even LIFR
conditions in areas of precipitation...especially from late morning
through early evening when convection will be at it's peak. This
includes...kcos...kpub and kals taf sites as they...too...will be
subject to hit or miss showers today into the evening. Flying over
the higher terrain could also be pretty Dicey...as heavy snow
showers will be possible...mainly above 10000 feet. Ceilings/visibilities
could go right down to zero in areas of heavy convective snowfall
and/or thundersnow. Precipitation will wind down this evening with
improving conditions from west to east as upper low pulls away
from the area. Lw

&&

Pub watches/warnings/advisories...
none.
&&

$$

Short term...lw
long term...Moore
aviation...lw