Area Forecast Discussion
Issued by NWS
FXUS61 KPBZ 281031
Area Forecast Discussion
National Weather Service Pittsburgh PA
631 AM EDT Sun Aug 28 2016
Thunderstorm chances will increase today as warmth and humidity
fuel a crossing disturbance.
.NEAR TERM /THROUGH TONIGHT/...
No major changes were needed for the dawn update as warm, moist
air has enfiltrated the Upper Ohio Region under broad upper high
Another in series of shortwaves across the northern periphery of
the Eastern CONUS ridge should support some afternoon storms, although
coverage is blurry given the various model depictions. For now, have
increased POPs mainly over areas north of I 70 where the ridge and
mid level temperatures show weakness, but have limited the numbers
to the "scattered/chance" category given weak flow and questionable
boundary focus. Convection should fade with the night, but will
not eliminate POPS entirely despite the stabilized boundary layer
as shortwave energy extending from Canadian low pressure is progged
to continue carving the aforementioned ridge perimeter.
Near-term temperatures nearly 10 degrees above the averages are
again anticipated with the more humid airmass.
.SHORT TERM /MONDAY THROUGH WEDNESDAY/...
Low pressure is forecast to dig over Eastern Canada, with trough
extension over the Northeast U.S. by Monday morning. The
associated surface front may continue to provide focus for
diurnally-enhanced convection over southern zones on Monday, but
building surface high under northwest flow should suppress precip
by Tuesday. The POP forecast has been adjusted for that
eventuality, and for small rain potential with the reinforcing
front on Wednesday.
Short term temperature will be in decline as an Eastern CONUS
trough develops. These were forecast near, or a couple degrees
under the averages using SuperBlend guidance.
.LONG TERM /WEDNESDAY NIGHT THROUGH SATURDAY/...
Eastern CONUS upper troughing will result in cooler Upper Ohio weather
until the ridge rebuilds next weekend. Temperatures a few degrees
under the averages, with moderation by Saturday, and minimal POPs
were forecast using Superblend guidance.
.AVIATION /10Z SUNDAY THROUGH THURSDAY/...
Ridging should maintain VFR conditions through the first part of
today. Scattered thunderstorms are expected to develop this
afternoon and evening with the approach of a weak cold front.
Will include a VCTS mention in the TAFs for now for the most
likely time of occurrence.
.OUTLOOK /MONDAY THROUGH THURSDAY/...
Restrictions are possible Monday mainly S of PIT as the front
completes its passage, and again with another crossing front