Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Pueblo Colorado
1119 PM MDT Monday Aug 3 2015
Short term...(this evening through tuesday)
issued at 238 PM MDT Monday Aug 3 2015
An upper trough will continue working its way northeastward over Colorado through
this evening...and will continue producing showers and thunderstorms during
this time over northern and eastern Colorado. Satellite images show drier air
working its way eastward behind this upper trough. Over the forecast
area...much of the more widespread and heavier precipitation associated
with the upper trough will likely be working its way north and east of
the area by late afternoon or early evening...but the hrrr is
showing another round of convection moving eastward off the eastern
mountains after about 01z.
With sufficient cape and marginal shear...there is the possibility
of one or two storms becoming severe or marginally severe through early this
evening over the eastern plains. By midnight much of the convection
should have ended...although some lingering activity could continue
over the far southeastern plains a bit longer.
An upper ridge will then be building over the area through Tuesday. Although
there will be drier air over the area on Tuesday...there will still be enough
moisture around for some isolated mainly afternoon showers and
thunderstorms...mainly over and near the hyr terrain.
Long term...(tuesday night through monday)
issued at 238 PM MDT Monday Aug 3 2015
..monsoon returns for the weekend...
High pressure will build strongly from the south for the middle-week
period...as the 500 mb center shifts over central nm. A weak shortwave
will cross through Wyoming Wednesday night...but most of the impact will be
north of our County Warning Area. This disturbance could spark some isolated to CT
storms over the mts late Wednesday...but otherwise it will be dry...and
the weak zonal flow will bring the upper 90s back to most of southeast
Colorado...along with 80s for the higher elevations. Thursday looks even
more hot and dry...with temperatures possibly around 100 degrees for the
hot spots along the lower Arkansas Valley. Another weak disturbance
will move through the ridge late in the day...but ts coverage should
be isolated at best.
Friday will continue to be warm as the upper high shifts back eastward
into Texas...and SW flow establishes itself over Colorado. The monsoonal plume
will begin working its way back into western Colorado as a trough moves ashore
over northern California...and then translates northeastward into the inter-mountain region
on Saturday. Expect widespread storms over the mts through Sat night
as the departing trough strengthens monsoonal flow into SW Colorado. The
eastern zones may not see as much widespread precipitation coverage...but still
should see at least isolated-scattered afternoon and evening storms.
Beyond Saturday...the forecast becomes a bit more uncertain. Model
consensus suggests that the upper high will gradually shift back to
the west...bringing our area back to a dry and hot Summer pattern.
But how fast this will occur is debatable. The GFS returns US to this
dry and hot pattern as soon as Sunday...while the European model (ecmwf) holds off
until later next week. The ensembles make it clear that there will be
a trough somewhere over the pacnw...and a ridge somewhere over the
Southern Plains...but subtle shifts in the overall pattern will
determine daily probability of precipitation and temperatures. So...persistence seems to be the
best bet at this point...with no significant precipitation and temperatures at or
slightly above average for this period. Rose
Aviation...(for the 06z tafs through 06z Tuesday night)
issued at 1117 PM MDT Monday Aug 3 2015
VFR conditions are anticipated during the next 24h at all 3 taf
sites...kpub...kals and kcos. Winds will be light and diurnally
Drier air is moving into the region tonight. Although I cannot
rule out an isolated thunderstorms and rain tomorow afternoon at any of the 3 taf
sites...the probability of it occurring is quite low at this time.