Area Forecast Discussion
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FXUS61 KPBZ 200556
Area Forecast Discussion
National Weather Service Pittsburgh PA
156 AM EDT Thu Oct 20 2016
Advancing low pressure will spread more widespread rain over the
Upper Ohio Valley Region tonight and Friday.
.NEAR TERM /THROUGH TODAY/...
Minor tweaks to PoPs and sky cover as forecast for the remainder
of the night is generally on track.
Low pressure developing along the front stretched over the Ohio
Valley will dig northeastward as mid level troughing amplifies
over the Plains tonight. Current convection over southern Ohio is
slowly eroding, while rain showers north of the convection congeal
further. Expecting this batch of moderate rain showers to follow
the warm front lifting northeastward across eastern Ohio and
northwest Pennsylvania. This is serves as the location for
categorical PoPs tonight, along with the passage of the cold front
Leaned closer to OHRFC guidance for the QPF of this system which
projects a general one to just-over-two inches over the next 48
The Storm Prediction Center has included the immediate area in a
"marginal/5 % severe risk on Thursday due to the shear levels on
the flank of the negatively tilting upper trough. Limitations will
be imposed by instability levels, which do not look healthy for
the situation depending on model; hence, no hazardous mention will
be included for now.
.SHORT TERM /TONIGHT THROUGH SATURDAY/...
The frontal precipitation will drift eastward Friday morning with
additional showers developing behind the boundary in the strong
cold air advection and passage of the upper level trough axis.
Much colder weather will follow for the weekend as the upper
trough develops over the Eastern CONUS. Scattered showers will
remain in the forecast through at least Saturday morning, with
focus shifting to the north and ridge zones, as cold advection
continues and shortwaves in northwest flow traverse the area.
By Saturday afternoon, the much drier air aloft, which will work
to suppress inversion heights, will eventually make it closer to
the surface, bringing and end to any lingering showers. Still
expect to see a good deal of cu over the area Saturday with the
cold pool aloft remaining anchored over the area.
.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
Dry, but seasonably cool conditions will return Sunday as warmer
air slowly works back into the area. Ensemble solutions continue
to push a weak front through the area sometime on Monday, which
may provide another risk for scattered showers. High pressure
builds in for the remainder of the long term.
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
-- Changed Discussion --Convective complex in southeast Ohio is moving towards western PA
at this time, bringing brief IFR conditions in heavy rain to BVI
over the next hour, and possibly PIT soon thereafter if it holds
together. FKL may be impacted with IFR in a couple of hours as
well as lighter rain develops. Mostly VFR conditions will hold
southeast of a PIT/DUJ line. Behind an advancing warm front,
conditions will remain VFR in the warm sector today as rain
coverage temporarily wanes, although MVFR ceilings may hold on
north of I-80.
As the cold front advances this afternoon, coverage of showers and
storms will increase from west to east, eventually overspreading
the region tonight. Flight conditions will deteriorate through
MVFR to IFR by the end of the TAF period.
.OUTLOOK /THURSDAY NIGHT THROUGH MONDAY/...
Periodic restrictions are expected through Saturday as low
pressure and subsequent upper troughing cross the area.
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