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Area forecast discussion 
National Weather Service Pueblo Colorado
431 am MDT Friday Aug 29 2014

Short term...(today and tonight)
issued at 338 am MDT Friday Aug 29 2014

Current water vapor imagery and upper air analysis indicating
subsident northwest flow aloft across state with yesterdays passing
upper trough continues to lift out across the High Plains as
stronger westerly flow continues across the Pacific northwest and northern tier
of states. Water vapor imagery is also indicating a short wave
embedded within the westerly flow translating across the northern
Great Basin at this time. Regional satellite imagery indicating
generally clear skies across the area with some clouds exiting the
far southeast plains and some clouds currently moving into western
Colorado. The dry and subsident northwest flow aloft and mainly
clear skies has lead to a crisp morning with current readings in the
30s and 40s across the higher terrain and 40s and 50s across the
lower elevations.

Latest models are in fairly good agreement of flow aloft becoming
slightly more westerly as northern Great Basin short wave moves
across eastern Utah early this afternoon and then continues into
southwestern Colorado and into the southern rockies through tonight.
Increasing middle and upper level moisture..along with some upward vertical velocity ahead
of said wave will lead to isolated to scattered showers and
thunderstorms this afternoon and evening...mainly over and near the
higher terrain. The westerly flow aloft will also allow for a few
storms to push out across the I-25 corridor through the late
afternoon and early evening hours. Soundings indicating generally
inverted v soundings with moisture increasing at or above h6 and continued
drying in the subcloud layer leading to gusty winds and lightning
being the main threats from storms that develop today. Should see
convection diminishing through the evening...though models are trying
to develop some warm air advection showers mainly southeast and northeast of the
area overnight. This looks a tad overdone although I did keep silent
probability of precipitation across southeast Colorado through the overnight hours. Temperatures
aloft warm a few degrees c today owning to a 3-7f bump in highs
across the area from yesterday.

Long term...(saturday through thursday)
issued at 338 am MDT Friday Aug 29 2014

Upper trough moves onshore Saturday across the Pacific
northwest...then tracks into the northern rockies Sunday. There
may still be enough moisture over the area Sat to produce isolated
high-based thunderstorms and rain in the afternoon...with westerly flow aloft
pushing storms onto the plains by early evening. With less
moisture available on sun...thunderstorms and rain coverage will be fairly
sparse...as best chances for any precipitation will be over the central
mountains near the approaching upper jet. Maximum temperatures both Sat/sun
should run above seasonal normals...and readings could reach the
middle 90s over the lower Arkansas Valley sun as deep mixing develops.

Upper trough moves into the northern plains sun evening as surface
cold front pushes south through Colorado. Given strongest upper forcing
is well north and moisture is limited across southern
Colorado...expect any thunderstorms and rain with the frontal passage to stay well
north and east of the region. Weak easterly flow develops over
the plains behind the front Mon/Tue...but moisture transport looks
too weak to produce convection...especially Monday as air mass will
stay fairly stable. European model (ecmwf) has a secondary wave and cold front
moving across the area Monday night...while the GFS has little sign
of this feature and instead lifts the upper jet fairly quickly
back north into the northern plains. Models in either case keep
most of the region dry Monday night into Tuesday...with thunderstorms and rain chances
limited to area along the Kansas border where low level moisture is
deepest. Maximum temperatures Monday should cool slightly following the frontal
passage...before new warming trend begins on Tuesday. Wednesday/Thursday look hot
and fairly dry under southwest flow ahead of the western U.S.
Upper trough...though some middle level moisture may work far enough
north to spark a few thunderstorms and rain along the Continental Divide Thursday
afternoon. Evolution of the western U.S. Trough late week still
rather unclear...though it appears a resurgence of the monsoon may
be possible by next weekend as tropical moisture begins to push
northward.

&&

Aviation...(for the 12z tafs through 12z Saturday morning)
issued at 338 am MDT Friday Aug 29 2014

VFR conditions expected at cos...pub and als over the next 24 hours.
Isolated high based storms can be expected across the higher terrain
this afternoon...with a few storms possibly sliding east across the
adjacent plains late this afternoon and early evening. Best chances
of storms affecting terminals will be at cos...though will maintain
thunderstorms in the vicinity at this time. Storms today will produce gusty winds and generally light
precipitation.

&&

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

$$

Short term...mw
long term...petersen
aviation...mw

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