Area Forecast Discussion
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FXUS61 KPBZ 310823
Area Forecast Discussion
National Weather Service Pittsburgh PA
423 AM EDT Wed Aug 31 2016
Warm weather continues today. A cold front will bring scattered
showers and thunderstorms later today and tonight. A cooler
pattern will follow for the remainder of the week.
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Large scale ascent will hold off until this afternoon, as a
deepening shortwave trough crosses the area. Deeper moisture will
quickly increase ahead of the upper level wave, providing the
risk for showers and storms. The activity will be timed along the
surface boundary which will enter Northwest Pennsylvania early
this afternoon and reach PIT as evening approaches. PoPs have been
timed and increased in accordance with the movement of the front.
Atmospheric instability will be available for the front to tap
into, but cloud cover will be a limiting factor on thunderstorm
development. At this time, the main threat appears to be heavy
downpours, as PWAT values remain quite high.
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/...
PoPs will decrease from north to south tonight, as what is left of
the surface boundary, moves into Northern West Virginia this
evening. A post frontal trough could spark a few showers tonight,
so held on to PoPs just a bit longer then previous forecast.
Surface high pressure builds in Thursday, as an upper level
trough sets up over the Upper Ohio Valley. The flow aloft will
usher in a drier and cooler air mass, which will remain in place
.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
The extended forecast will be very quiet through the holiday
weekend. Ridging is progged across much of the eastern CONUS
through Labor Day, with dry weather and gradually warming
temperatures. Clouds may be on the increase on Tuesday, but
precipitation should still remain west of the area.
.AVIATION /09Z WEDNESDAY THROUGH SUNDAY/...
VFR conditions are expected through much of Wednesday. A cold
front will move across the region late morning into the evening,
with scattered showers and thunderstorms. Issue will be where more
widespread shower can develop for restrictions. Used a broad
brush with vfr showers from north to south through the day, with
VCTS for a time. Better timing on more precise restrictions may be
possible for terminals for the afternoon. Winds will be west under
10 KTs until turning north under 10 KTs behind front in the
afternoon. Cold advection will bring some MVFR stratus Wednesday
night well behind the front.
.OUTLOOK /THURSDAY THROUGH SUNDAY/...
VFR conditions under high pressure through the weekend.