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Area forecast discussion 
National Weather Service Pueblo Colorado
1104 PM MDT Wednesday Aug 20 2014

issued at 636 PM MDT Wednesday Aug 20 2014

Updated forecast to adjust for near term trends. Looks like a few
isolated showers/ts could hang on over the mts and eastern plains this
evening...but trend is downward and coverage will be minimal so have
dropped most of the probability of precipitation below 10 percent for tonight. Rose


Short term...(this evening through thursday)
issued at 238 PM MDT Wednesday Aug 20 2014

Upper level low is sitting along the Southern California coast today and is
expected to move little in the next 24 hours. WV satellite images
showing drier air has worked it way into western Colorado today. Hrrr and rap
showing mainly isolated precipitation coverage this evening over western
portions of the forecast area...with isolated to scattered coverage over
the eastern mts and southeastern plains. A weak boundary is forecast to move
into the Palmer dvd area early this evening and then work its way
south. This boundary may help kick off additional convection. There
could be a few lingering showers or thunderstorms over the southeastern plains...but
think that most of the precipitation should end by 06z.

On does not look all that moist over the forecast area.
Precipitable water values over western areas are forecast to be similar
to today...with drier conditions over eastern areas. As a result the
forecast models show mainly isolated to scattered probability of precipitation over the mountains in the
afternoon hours...with possibly a few storms over the lower
elevations. High temperatures for Thursday should be around average in the high
valleys...with slightly above normal readings over the southeastern plains.

Long term...(thursday night through wednesday)
issued at 238 PM MDT Wednesday Aug 20 2014

Not much change to the forecast thinking with the GFS coming into
line with the European model (ecmwf) and NAM solutions. Ensembles are still
displaying quite a bit of spread by early next week...but
confidence is a higher than it was yesterday in a forecast

An upper level disturbance over Southern California is forecast to
eject northeast across Colorado on Friday. Expect a few showers
and thunderstorms to be ongoing Thursday evening and dissipating
through midnight over the mountains...with perhaps a few lingering
showers over the Palmer Divide into northeast Colorado into early
Friday morning.

Friday has the potential to be interesting. The upper disturbance
over Arizona will eject across Colorado through Friday evening.
Models quick to advect moisture north across Colorado...and shear
looks to increase to around 30 kts or so by the afternoon with
modest instability. Expect shower and thunderstorm development by
middle morning Friday along the Continental Divide...and spreading
east into the I-25 corridor by early in the afternoon. Model quantitative precipitation forecast
fields are indicating that heavy rainfall will be
possible...especially over the mountains and locations over the
Palmer Divide. Flash flooding will be possible on area burn scars
and flood prone areas Friday afternoon and evening. Some storms
across the plains could become strong...with small hail and gusty
outflow winds also possible. Models in good agreement with
thunderstorms shifting east across the plains Friday night with
all activity exiting into Kansas by Saturday morning.

Saturday will likely be a pretty quiet day across southern
Colorado given subsidence behind the departing upper system. A
couple of afternoon and evening showers and thunderstorms will
remain possible over the mountains...but coverage looks to be

A broad trough will persist over the western Continental U.S. Through the
middle of next week with a couple of more disturbances moving
across southern Colorado. The next one looks to move across the
region on Sunday. This will bring another uptick in shower and
thunderstorm activity across the state...with activity starting
over the mountains late Sunday morning and spreading east through
the afternoon and evening. In addition...a cold front will move
south across the plains during the afternoon...turning low level
flow upslope...which will likely aid precipitation development
across the plains Sunday afternoon and evening.

Models a bit different on the arrival of the next disturbance
dropping across The Rockies...with GFS has been bringing it
through Monday evening...with the European model (ecmwf) is a bit slower on
Tuesday. This will likely lead to another round of decent
precipitation for the mountains...and spreading east into the
plains sometime in the Monday to Tuesday time frame. This system
looks to be accompanied by a strong cold front which should help
the plains see another shot for precipitation. Mozley


Aviation...(for the 06z tafs through 06z Thursday night)
issued at 1049 PM MDT Wednesday Aug 20 2014

..significant impact possible on Friday...

Isolated storms will develop over the mountains Thursday
afternoon. Storms will become more numerous after 00z as
a low pressure system moves into Colorado. Isolated-scattered storms
will be possible through Thursday night...but the main AVN concern
will come on Friday as the upper level storm system moves
through. Widespread precipitation and storms with the potential for
heavy rain and persistent MVFR-IFR ceilings will be possible from
Friday 15-18z on through Friday evening and possibly into Sat
morning...especially east of the sangres and ramparts. Rose


Pub watches/warnings/advisories...


short term...28
long term...mozley

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