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fxus61 kpbz 241412 

Area forecast discussion
National Weather Service Pittsburgh PA
1012 am EDT Fri Mar 24 2017

a period of above-normal temperature and increasing chances for
rain is expected through early next week.


Near term /until 6 PM this evening/...
with 1015am update, made some minor tweaks to pops, sky, and
hourly temperatures. Although radar mosaic shows plenty of radar
echoes across Ohio and western Pennsylvania, this is mostly
virga - precipitation that is evaporating before reaching the
ground due to the dry air near the surface. Previous discussion

Morning update to speed up the exodus of moderate rain.
Stratiform rain has really sped through the area this morning,
leaving only unorganized scattered light showers in its wake.
Rising upper level heights will follow the exiting wave pushing
a warm front further north. By late morning, the area will be
well into the ever expanding warm sector, stabilizing the
atmosphere, and keeping the rest of the day dry. Southwest wind
and strong warm advection will support temperatures above
average, despite mostly cloudy skies.


Short term /6 PM this evening through Sunday/...
a series of compact shortwave troughs will develop in the swrn
Continental U.S. And eject northeastward beginning Saturday. As the first
wave acquires a negative tilt, shortwave ridging will amplify
over the Great Lakes region, leading to a likely-nwd
displacement of precipitation on Saturday and Saturday night.

Steady height falls will begin to spread across the region
Sunday morning as the ejecting wave nears. By afternoon, the
associated 500 mb jet maximum will cross the forecast area, likely
invigorating deeper convection with its passage amid modest


Long term /Sunday night through Thursday/...
in the wake of the Sunday wave, a brief respite can be expected
on Monday amid shortwave ridging before a second trough ejects
from the plains. This second wave will be favorable for
widespread rain showers as it crosses on Tuesday as warm, moist
air is drawn poleward ahead of the system.

Behind the wave, seasonable air is expected to arrive mid-week.


Aviation /14z Friday through Tuesday/...
scattered light rain showers will linger through late morning,
before a return to mainly dry weather in the warm sector of a
broad low pressure system. Additional moisture will pool along a
warm front located just north of the area tonight. This could
bring restrictions with ceilings descending to low MVFR or IFR
for northern ports of fkl/duj.

the next chance for widespread restrictions is not expected
until the approach of low pressure early on Sunday.


Pbz watches/warnings/advisories...

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