Area Forecast Discussion
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FXUS61 KPBZ 251826
Area Forecast Discussion
National Weather Service Pittsburgh PA
226 PM EDT Sun Sep 25 2016
Showers and scattered thunderstorms can be expected with a Monday
.NEAR TERM /THROUGH TONIGHT/...
Dry high pressure will continue to suppress clouds and precip
into Monday. A warming column/developing warm advection and
encroaching early morning stratus from east of the ridges should
offset initially efficient radiation tonight. Overnight lows were
thus projected several degrees below most guidance, especially
over eastern counties, but not quite as cold as last night.
.SHORT TERM /MONDAY 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
dependant 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 /18Z SUNDAY THROUGH FRIDAY/...
General VFR is forecast through Monday morning with condition
deterioration thereafter in response to precip with an approaching
.OUTLOOK /MONDAY NIGHT THROUGH THURSDAY/...
The next chance for restricition is expected under deepening mid
week low pressure.