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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KPBZ 191653
AFDPBZ

Area Forecast Discussion
National Weather Service Pittsburgh PA
1253 PM EDT Tue Sep 19 2017

.SYNOPSIS...
Generally warm and humid conditions will prevail for the next
week across the area.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Main change was to increase and expand PoPs eastward a bit
to UCP and the northern WV panhandle. 12Z soundings show a
cap above 700mb at KPIT but no such feature at KILN. Model
soundings suggest that the cap at the office will hold on, just
barely, suggesting a decent eastern edge to precipitation
chances. While the bulk of the activity to our west will fall
apart as it bumps into the ridge over the CWA, the HRRR looks
reasonable in suggesting isolated/scattered convective
development in the western counties during the afternoon hours.
Equilibrium levels above 30k feet suggest thunder possibilities
and have added it in. Temperatures are in good shape and made
few changes there.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY NIGHT/...
While the front continues to struggle to advance eastward
through tonight and into Wednesday, the attendant mid-level
circulation and weakening cold pool will give it a whirl on
Wednesday. GFS/EC guidance suggest it should start to slink SE
as is weakens rapidly from afternoon into evening, and the bulk
of the mid-level cooling is likely to remain to the SW of the
area as it transits SE and falls apart. With that in mind, a
chance/slight chance mention of rain showers will remain in the
forecast for Wednesday afternoon/evening, especially over
eastern Ohio and northern West Virginia.

With the passage of the wave Wednesday, high pressure will again
resume control with steady warming into the latter half of the
week. Fries

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
Deepening troughing over the western CONUS and amplified ridging
over the eastern CONUS will yield strong warm advection into the
Ohio Valley through the weekend and beyond. This will be
especially true as surface high pressure slowly trudges from
directly overhead to ever-so-slightly east of the area by early
next week. This will increase mixing potential, decrease any
easterly moisture fetch into the area over the ridges, and yield
a surge in 850 mb temperatures toward +17 to +19C for several
days. As a result, highs in the lower elevations will jump at
least toward the mid 80s, if not higher, and even in the higher
terrain, upper 70s will be possible.

With high pressure in control, and ridging amplifying overhead,
no rainfall is anticipated during the long term or beyond. Fries

&&

.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
-- Changed Discussion --
VFR conditions with diurnal CU and increasing mid/high clouds
are expected into the overnight hours as a weak upper trough
approaches. Clouds should limit fog potential again tonight/Wed
morning., but will go with some restrictions at AGC/FKL/DUJ
where less cloud cover could allow for some fog development.

.Outlook...
Other than local morning fog, no widespread restrictions
expected through Sun with building ridging.
-- End Changed Discussion --

&&

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

&&

$$