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fxus61 kpbz 291411 

Area forecast discussion
National Weather Service Pittsburgh PA
1011 am EDT Wed Mar 29 2017

high pressure will ensure dry weather today before another low
pressure system brings rain to the region late Thursday through


Near term /through tonight/...
with 10am update, minimal changes were made to cloud cover and
hourly temperature grids as clearing occurs from north to south.

High pressure ridge building overhead will maintain dry
conditions today and tonight. Thick stratus deck should
diminish this morning once daytime mixing takes place, allowing
US to warm close to, if not slightly above seasonal averages.

Clear skies tonight, albeit not perfect for radiational cooling
with some surface wind, should allow for US to cool off early.
However, strengthening warm advection aloft should become a
limiting factor as we go toward Thursday morning. Thus, a non-
diurnal trend is forecast with lows close to seasonal averages.


Short term /Thursday through Saturday/...
high pressure should keep the region dry through Thursday
morning, with guidance trending even a bit slower with the
arrival of precipitation. Still, will increase pops to likely by
Thursday night as deep, moist, southerly flow in advance of the
occluding low supports these values. Broad low pressure will
slowly slide eastward through Friday, maintaining rain chances
through much of the day. The weakening upper low will shift east
by Saturday morning, but lingering low level moisture may keep
widely scattered showers possible through the first part of the
day before building subsidence brings an end to precipitation.

Temperatures will continue to run slightly above seasonal
averages through the period, including on Friday, despite rain
with strong warm advection expected.


Long term /Saturday night through Tuesday/...
very little change in the pattern is expected as model guidance
continues to show a series of low pressure systems ejecting out
of the southwestern Continental U.S. And lifting toward the Ohio/Tennessee
valleys. This will maintain at least chance pops through midweek
outside of dry conditions expected Sunday. With some uncertainty
in low track and speed, a blend of guidance was used.
Temperatures will generally stay close to averages for early April.


Aviation /14z Wednesday through Sunday/...
fairly expansive MVFR cloud deck in place this morning, but
latest satellite imagery trends show some breaks/erosion
beginning to chip along the northern fringe. Clearing
associated with high pressure building in from the north will
first find fkl/bvi/duj working southward thereafter. All
locations expected to achieve VFR near midday.

Light north winds will persist through much of today. These will
gradually shift easterly by Thursday, but generally remain less
than 10kts.

restrictions are likely again from late Thursday through
Saturday as another broad low affects the upper Ohio Valley.


Pbz watches/warnings/advisories...

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