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000 
FXUS61 KPBZ 202016
AFDPBZ

Area Forecast Discussion
National Weather Service Pittsburgh PA
416 PM EDT Sun Oct 20 2019

.SYNOPSIS...
Warmer conditions are expected Monday before the passage of a
Tuesday cold front. Near-average temperature and dry conditions are 
then expected by mid week under high pressure.

&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
Shortwave ridging in the wake of the exiting Nestor will maintain dry
weather and seasonably warm conditions for tonight. A clear sky and
light wind will support patchy, shallow fog as crossover temperature
will likely be achieved.

&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH WEDNESDAY NIGHT/...
A deepening, closed upper low will advance toward the Upper MS 
Valley, promoting strong sly flow over the Ohio Valley. Despite 
increasing cloud cover, warm advection will enable daytime high 
temperature to reach 10-15 degrees above average. 

Rain coverage should expand from west to east Monday night as the
boundary layer saturates with increasing low level jet support ahead
of an encroaching cold front. Strong forcing for ascent of precipitable
water in excess of 1.40" (+ 90% climatological average) should 
support periods of moderate rainfall through Tuesday morning as the 
cold front quickly advances through the forecast area.

Subsiding air in building high pressure will support a drying trend
Tuesday behind the cold front. Lingering low level moisture should 
fuel the development of a cumulus deck under broad upper troughing 
Tues afternoon, with strong wind mixing to the surface via steep 
low-level lapse rates and a decent gradient wind.

Cold advection behind the front will return daytime high temperature
to near average values. Similarly, as dry air and clearing sky ensue
Tue night in the wake of the upper wave, minima will also end up 
near seasonal average.

Quasizonal flow aloft and surface high pressure should support a dry
and seasonably cool Wed.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
Although long range models diverge on details, the consensus 
suggests return flow ahead of a deepening Plains trough, supporting 
at least seasonable temperature in the long term. Precipitation 
chances will be dictated by shortwave activity in SWly flow aloft
ahead of the aforementioned trough.

&&

.AVIATION /20Z SUNDAY THROUGH FRIDAY/...
Shortwave ridging wl maintain VFR through Monday with the only
interruption being the potential for peri-dawn fog.

.Outlook...
Restrictions are likely Monday night into Tuesday with a frontal 
approach, subsequent passage, and coincident rain.

&&

.PBZ WATCHES/WARNINGS/ADVISORIES...
MD...None.
OH...None.
PA...None.

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