Scientific Forecaster Discussion
fxus61 kpbz 280706 cca
Area forecast discussion...corrected
National Weather Service Pittsburgh PA
306 am EDT Wed Jun 28 2017
high pressure should maintain dry weather today. An approaching
front will return shower and thunderstorm chances to the area
late this week.
Near term /until 6 PM this evening/...
dry weather and mostly sunny skies are expected today as high
pressure slides across the region. High temperatures are
expected to be around 5 degrees below the seasonal average.
Short term /6 PM this evening through Friday night/...
some increase in cloud cover is expected tonight in warm
advection ahead of an approaching shortwave as the high exits
the mid Atlantic coast. This wave is progged to track across srn
Ontario and northwest PA Thu, with shower and thunderstorm chances
increasing mainly near and north of I 80. Shear is progged to
increase, though unfavorable lapse rates and instability should
limit any significant severe weather potential.
Another, weaker shortwave is progged to take a similar track
early Friday, maintaining precip chances. Shortwave ridging
behind the second wave should result in limited shower and
thunderstorm coverage during the afternoon despite building
instability. Warm mid levels should also help limit convection.
Maintained low chc pops Friday night with another weak shortwave
ahead of an approaching midwestern upper trough. A return to
above average temperatures is expected by Thursday.
Long term /Saturday through Tuesday/...
the midwestern upper trough is progged to advance east Saturday
driving a cold front across the area. Dry weather is expected to
return sun/Mon as surface ridging builds underneath the upper
trough. Another trough is progged to advance east from the Midwest
and plains regions Tue, though with uncertainty in timing and
location limited pops to the chance category for now on the 4th
Aviation /07z Wednesday through Sunday/...
VFR through the forecast period.
restriction chances will increase during the latter half of the
week with the approach and passage of a cold front.