Area forecast discussion
National Weather Service Pueblo Colorado
1114 am MDT sun may 19 2013
Update...
issued at 1054 am MDT sun may 19 2013
Updated to reduce chances for showers and thunderstorms across the
plains for this afternoon and evening. Based the forecast off the
NSSL WRF and caic WRF runs...which only have isolated activity
across the plains...and therefore reduced our probability of precipitation to match. Given
the dry air at the surface...it may be hard for any precipitation
to reach the ground...and we will likely see gusty outflow winds.
Elsewhere the forecast looks on track with light snow falling
above 9 kft through this evening. Mozley
&&
Short term...(today and tonight)
issued at 410 am MDT sun may 19 2013
..cooling trend continues...
Current water vapor imagery and upper air analysis indicating
generally weak west to northwest flow aloft across the area with an
upper low developing across the northern High Plains and a broad
upper trough hanging back across The Rockies and the intermountain
west at this time. Water vapor imagery also indicating an embedded
short wave lifting out across the eastern plains helping to fuel
thunderstorms across northeast Colorado and northwestern Kansas at
this time.
Today...broad upper trough to persist across the area as northern
High Plains upper low continues to slowly lift out into the Dakotas
through the afternoon. Latest models continue to indicate steep
lapse rates in place across the area and along with late Spring
sunshine...will see scattered showers and thunderstorms developing
through the late morning and afternoon across the higher terrain.
Passing wave sends a back door cold front across the eastern plains
which also helps to generate showers and storms across the plains.
Model soundings still indicate mainly high based storms with
continued inverted v profiles. Moisture profiles...however...are a
little deeper than yesterday...with LCLs between h65 and h6...which
supports slightly better chances of precipitation making it to the
ground...especially across the higher terrain. With cooling aloft as
well as at the surface with passing cold front...highs today will follow
the trend with mainly 60s and 70s across the plains...50s and 60s
across the higher terrain and only 30s at Montana tops. With that
said...could see light accumulations of a couple of inches on the
higher peaks.
Tonight...models continue to indicate generally weak west to
northwest flow aloft across the area with another short wave
rotating around upper Midwest low across western Wyoming and into
northwestern Colorado by early Monday morning. Showers to diminish
across the area the early evening with loss of heating with probability of precipitation
increasing once again across the central mts after midnight with
increasing upward vertical velocity ahead western Wyoming wave. With a cool air mass in
place and partial clearing skies through the late evening...could
see sub freezing temperatures across the high Montana valleys.
Long term...(monday through saturday)
issued at 410 am MDT sun may 19 2013
On Monday an upper low will be centered over South Dakota with an upper trough
extending southwest into eastern Colorado. Northwest flow and good moisture into the
central mts and over the Pikes Peak and Teller County area...should lead
to good chances for precipitation in those locations through the day. In the
afternoon hours a shortwave trough is expected to make its way
southward over the area in the northwest flow behind the trough axis...and
is expected to aid in kicking off additional showers and a few
thunderstorms across much of the area. Temperatures on Monday are expected to
be below normal. By late Monday night most of the precipitation should end but
moist northwest flow should continue to bring some showers to the central
mts...and possibly to eastern portions of the forecast area north
of Highway 50. Temperatures will be cold enough at the high elevations for
some snow accumulations with several inches likely over the
central mountains and over Pikes Peak.
The upper low will be very slow moving and on Tuesday is expected to be
centered over eastern South Dakota...while a shortwave ridge builds over Utah and
pushes into western Colorado. Some lingering moisture and instability...along
with a weak disturbance moving into western Colorado...should allow for the
development of isolated to maybe scattered precipitation mainly over the mountain
areas. Temperatures Tuesday should be a little warmer and should be around
average. The upper disturbance is then expected to work its way
eastward across Colorado Thursday night...possibly bringing some isolated precipitation to
the eastern plains as well.
On Wednesday the shortwave ridge moves across Colorado...but in the afternoon a
weak disturbance may move over the area and there may be enough
moisture for a few showers/thunderstorms to develop in the afternoon and
evening...mainly over the hyr terrain.
Thursday and Friday an upper low is forecast to be centered over the Pacific
northwest...causing increased SW flow aloft over the forecast area. Over
the southeastern plains surface high pressure will bring low level easterly flow
and increased low level moisture. The GFS is indicating the potential
for relatively high cape values and a surface boundary across the southeastern
plains each afternoon/evening with possibly some strong thunderstorms.
On Sat an upper trough is expected to remain over the western states and
the models are indicating an eastward shift in the low level moisture
and mainly dry conditions over the forecast area.
&&
Aviation...(for the 18z tafs through 18z Monday afternoon)
issued at 1054 am MDT sun may 19 2013
Showers and thunderstorms are expected over the higher terrain
through early evening. A few may drift east over the San Luis
valley to near kals between 19-02z this afternoon. Main threats
would be gusty outflow winds...but confidence in a cell hitting
the terminal is low. Models developing shower activity near kcos
by early afternoon. Gusty outflow winds will be the main threat
through 02z. Less certainty at kpub...for now will thunderstorms
in the vicinity...with any threats being gusty outflow winds.
Mozley
&&
Pub watches/warnings/advisories...
none.
&&
$$
Update...mozley
short term...mw
long term...28
aviation...mozley
