Area Forecast Discussion
Issued by NWS Pueblo, CO

Home | Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38
FXUS65 KPUB 210515

Area Forecast Discussion
National Weather Service Pueblo CO
1115 PM MDT Thu Apr 20 2017

Issued at 557 PM MDT Thu Apr 20 2017

Updated forecast based on latest radar trends.


.SHORT TERM...(This evening through Friday)
Issued at 336 PM MDT Thu Apr 20 2017

...Unsettled weather through Friday with Higher Mountain Snows...

Showers and isolated embedded thunderstorms have blossomed across
the mountains as of 21z in response to the upper trof across UT
advancing towards western CO.  SPC meso analysis shows a few hundred
J/kg of CAPE across the mountains areas and high res models indicate
the chance for thunderstorms through the evening across this area.
Localized brief moderate to heavy rainfall and some small hail and
lightning will be the primary storm risks.  Snow levels remain quite
high...around 10-10.5kft this afternoon but should drop to around
8kft or a little towards 12z Friday.  Primary snowfall accumulations
across the mountains will be along the crests of the
Sawatch/Mosquitos and Pikes Peak where advisories are currently in
effect through mid day Friday.

For late this afternoon and evening...showers and embedded
thunderstorms will spread out into the plains where models show
increasing WAA/overrunning overtop the surface high.  Best focus
will initially be along/north of highway 50 with KCOS seeing the
best chance for rainfall as south to southeast low level flow will
also provide an upslope component.  Doesn`t look particularly
heavy...but rainfall amounts of .10 to .40 will be possible. Overall
however...low level moisture is lacking therefore CAPE is limited so
as showers spread onto the plains suspect they will become more
stratiform in nature. Best lift from the trof impacts the area
around 06z and some high res models suggest a round of thunderstorms
will develop across northeast NM...skimming along the southern
border through the overnight hours.  For chance for
elevated severe thunderstorms appears to stay to the south of the
area but Baca/Las Animas counties may have to be monitored during
the overnight hours for some brief strong convection along the
northern fringes of the threat area.

Other concern will be potential for rainfall on burn scars. For the
most part expect that rainfall rates will remain below flash flood
warning levels...however newer burn scars (like Junkins and Hayden)
will be wild cards as any locally intense afternoon convection could
be sufficient to cause some localized run-off problems.  Although
risk is on the low side...should a stronger cell impact those burn
scars advisory level flooding could occur.  This threat decreases
after 06z as best lift shifts eastward.

Should be a lull as drier air spreads across southwest sections of
the area Friday morning.  Upper low closes off across far southeast
CO/SW KS and focus for showers and afternoon thunderstorms will
shift to the far southeast plains in area of wrap around
precipitation.  There could be some sufficient CAPE for a shallow
thunderstorm or two and with cold air aloft some small hail would be
possible near the CO/KS border Friday afternoon.  Otherwise most
area should see clearing conditions with breezy north winds on the
back side of the system. -KT

.LONG TERM...(Friday night through Thursday)
Issued at 336 PM MDT Thu Apr 20 2017

Friday night-Saturday night...Strong northwest flow aloft across the
region Friday night moderates through the day Saturday, with the
main trough continuing to dig south and east into the Southern High
Plains as secondary energy across the Northern Rockies digs south
and east across the Central High Plains on Saturday. With that said,
should see precipitation diminishing across the far southeast plains
late Friday afternoon and evening, with chances of light
precipitation continuing across the Eastern Mountains and immediate
adjacent plains Friday night and through the day Saturday, with
moist low level upslope flow and weak UVV associated with the
secondary lobe of energy. Subsidence behind the secondary lobe of
energy will allow for diminishing clouds across the area Saturday
night. Temperatures through this period will be at or below
seasonal levels, with overnight lows both nights flirting with the
freezing mark across portions of the plains. However, with expected
cloud cover Friday night, and warming aloft Saturday night, not
expecting a widespread freeze through the period.

Sunday-Monday night...Warmer and drier weather remains in the offing
for Sunday with upper level ridging building across the state. The
ridge flattens across the area Sunday night and Monday, as a minor
embedded wave translates across the Rockies. Models differ on timing
and location of this minor wave, though looks to mainly bring
chances of light precipitation to the higher terrain of the central
mountains on Monday. Temperatures through the period to be generally
above seasonal averages, with highs in the 70s and 80s across the
plains and mainly in 50s and 60s across the higher terrain.

Tuesday-Thursday...Models continue to indicate a more unsettled
weather pattern through the middle of the week, though differ with
timing and strength of said systems. At any rate, could see another
wave moving across the region on Tuesday, which again mainly affects
the higher terrain. A stronger wave looks to dig across the state
Wednesday night and Thursday, which could bring chances of
precipitation to all of south central and southeast Colorado.


.AVIATION...(For the 06Z TAFS through 06Z Friday night)
Issued at 1106 PM MDT Thu Apr 20 2017

Back edge of heavier convection moving east of KCOS and KPUB as
of 05z, and expect only vcsh at both sites for the remainder of
the night. With surface winds swinging back around to the se at
KCOS, suspect cigs will drop back into the ifr range 08z-13z, as
most surrounding airports are already below bkn010. With weaker
winds, cigs at KPUB should remain higher, though a period of MVFR
is possible 06z-12z. After 12z-13z, nly surge pushes through the
plains, which should scatter out lower clouds at both KPUB and
KCOS through the morning. Showers then redevelop across the
eastern mountains and plains by late morning and continue into the
evening, and will carry a vcsh mention at KPUB and KCOS until
00z-02z. Could see some MVFR cigs return to at least KCOS by late
Fri evening, as wind become sely once again. At KALS, precip has
shifted east, and expect VFR conditions overnight and through the
day Fri, with occasionally gusty nw winds.


Winter Weather Advisory until 3 PM MDT Friday for COZ058-060-082.



AVIATION...PETERSEN is the U.S. government's official web portal to all federal, state and local government web resources and services.