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fxus61 kpbz 230044 

Area forecast discussion
National Weather Service Pittsburgh PA
844 PM EDT Wed Mar 22 2017

a clear and cold night will be followed by sunshine and
moderating temperatures Thursday. Rain chances return by the end
of the week with a continued warming trend.


Near term /through Thursday/...
surface high pressure will continue to settle southward toward
the region late this evening. As is does so, stabilization will
continue to increase, thus ending the threat of gusting winds.
In addition, as the pressure gradient relaxes overnight, winds
will diminish to near nil, setting the stage for nearly optimal
radiational cooling conditions. That said, temperatures should
go into free fall with lows areawide generally in the teens.

As the surface high moves toward the Chesapeake Bay on Thursday,
weak warm advection will start to take over. This will allow for
temperatures to to their bounce upward. Even still, layer relative humidity
perspectives from the models favor a good deal of sunshine,
particularly in the first half of the day with modest mid and
high cloud increases during the afternoon. Fries


Short term /Thursday night through Friday night/...
warm advection and increasing moisture will continue Thursday
night in advance of a warm front. A north-to-south pop gradient
was maintained, with highest values in the likely category near
and north of I-80. At this time, it still appears that most
precipitation will be rain. A short period of freezing rain
remains possible along the leading edge, mainly in the DuBois
vicinity around midnight or so. This chance depends greatly on
the amount of cooling that can occur beforehand, which is
questionable given the increasing cloud cover. Still, some
evaporative cooling is possible depending on temp/dewpoint
spreads during the evening. Will continue with a low-confidence
freezing rain mention and maintain the severe weather potential statement mention as is.

Shower coverage will slowly decrease on Friday as the warm
sector becomes more firmly entrenched over the area. The
continued strong warm advection allow temperatures to rise to 5
to 10 degrees above normal levels. A few showers may linger
near/north of I-80 through Friday night, otherwise a mainly dry
period is foreseen with quite mild overnight temperatures.


Long term /Saturday through Wednesday/...
an active pattern is still forecast for the weekend into early
next week. Saturday may feature a few showers as moisture in the
warm sector continues to increase. An upper low ejecting from
the plains into the Great Lakes will push a front our way on
Sunday with good rain chances. Depending on timing, thunderstorms
will be possible during the afternoon and evening. The front
may linger near the area on Monday with some showers, before
another low threatens to bring higher rain chances once again
Monday night or Tuesday. Dry weather and high pressure may then
return by the middle of next week. Above normal temperatures are
a strong possibility throughout.


Aviation /01z Thursday through Monday/...
VFR conditions in clear skies will prevail tonight, with high
cirrus spreading over the terminals through the day tomorrow.
Wind gusts should diminish soon, if they haven't already, with
the surface ridge sliding overhead. Tafs are two lines for the
primary reason of showing the wind shift from WNW to ESE
tomorrow. Wind should remain under 10kts tomorrow.

the next chance for widespread restrictions should come on
Friday with a front tracking across the lower Great Lakes.


Pbz watches/warnings/advisories...

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