Area Forecast Discussion
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FXUS61 KPBZ 252247
Area Forecast Discussion
National Weather Service Pittsburgh PA
647 PM EDT Sun Sep 25 2016
Showers and scattered thunderstorms can be expected with a Monday
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
Surface high pressure will slowly edge from near Lake Ontario this
evening toward the Hudson River overnight. This will allow for
surface flow to slowly turn southeasterly over much of the area
overnight. Dry advection will wane this evening with dewpoints
likely creeping up from the southeast overnight as more moist
marine air advances northward up the east side of the ridges. Some
of this will become manifest as stratus into Tucker and Garrett
County, while the vast majority of the area will remain clear
overnight and still very dry. Some mid and high clouds will start
to encroach from the west by morning, however most areas will have
another dry and cool night before the first rain-maker in days
approaches for Monday. Fries
.SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY/...
A deepening mid level trough is projected to close over the
Northern Great Lakes on Monday as it drives a cold front across
the Upper Ohio. Likely to categorical precip probabilities are
forecast with this eventuality, while increasing deep layer shear
may support possible severe thunderstorms. That potential will be
dependent on timing, surface dewpoints, clouds, and resulting
instability levels, magnitude of which does not look strong enough
to initiate any alarms today.
Showers are forecast to exit eastward with the front during the
evening with dry and cooler conditions following on Tuesday. By
Wednesday, the closed low is progged to dig southeastward across
the Great Lakes, and increase clouds and shower chances for the
immediate area. Temperature about 5 degrees under the rapidly
falling averages was forecast using Superblend guidance.
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
The latest deterministic trends are of a persistent cutoff low
somewhere over the Mid Atlantic or Great Lakes States during the
long term. Have opted for a NAEFS mean solution which is of
troughing over the Upper Ohio, without the inconsistent magnitude
of the latest ECMWF and GFS solutions. Long term POPs are thus in
the slight, to low-end chance range, with a temperature prog which
allows a recovery to, then a couple degrees above the seasonal
averages by next weekend.
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
-- Changed Discussion --General VFR is forecast through Monday morning with condition
deterioration thereafter in response to precip with an approaching
cold front. Generally expecting MVFR restrictions accompanying any
stronger shower or thunderstorm, but temporary IFR visibilities
and gusty winds cannot be ruled out.
Winds will gradually strengthen Monday morning as they swing
around from the south. A sharp wind shift to the west will then
accompany the cold front, with gusts occasionally 15-20 knots.
.OUTLOOK /MONDAY NIGHT THROUGH THURSDAY/...
The next chance for restriction is expected under deepening mid
week low pressure.
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