Area Forecast Discussion
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FXUS61 KPBZ 281644
Area Forecast Discussion
National Weather Service Pittsburgh PA
1244 PM EDT Sun Aug 28 2016
Thunderstorm chances will increase today as warmth and humidity
fuel a crossing disturbance.
.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --Weak boundary will sink across the region through the period. A
few showers have already popped up in northern PA but consensus is
that coverage will increase this afternoon as we destabilize.
Most, if not all of the model guidance suggests greatest
thunderstorm chances will be north of I-70 supplemented by the
passage of a shortwave and very minimal cooling aloft. Steep low
level lapse rates would suggest some storms may produce strong
wind gusts through the evening, if they can maintain themselves.
With more cloud cover and thunderstorm development, temperatures
may be a degree cooler than yesterday. However, humidity levels
will be higher, maintaining the mid 90 heat indices.
Convection should fade with the loss of heating, but low chance
PoPs were maintained as shortwave energy extending from Canadian
low pressure is progged to continue carving the aforementioned
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.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 /18Z SUNDAY THROUGH FRIDAY/...
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