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Area forecast discussion 
National Weather Service Pittsburgh PA
1137 am EDT Sat Oct 22 2016

cool and unsettled weather today with a crossing upper level
disturbance. Dry weather should return Sunday under high pressure.


Near term /through tonight/...
adjusted afternoon pops based on a bit slower exit to the
northeast. Winds also brought down somewhat from previous
expectations. Remainder unchanged.

Lake enhanced bands of showers will continue to shift north and
east as the flow progresses through the afternoon. Cold advection
will continue through the morning, with a few snow showers mixed
in for the higher ridges and I-80 corridor into late morning.

As flow turns anticyclonic tonight showers will end, with warm
advection actually beginning after midnight as low pressure exits
toward New England. Winds will be gusty to over 40 miles per hour in the
ridges into this evening, then diminish overnight. Temperatures
will average 5 to 10 degrees below the seasonal average.


Short term /Sunday through Monday night/...
Sunday will begin dry as high pressure tracks well to our south.
Deamplifying flow aloft and gusty southwest winds will allow
clouds to decrease and push afternoon temperatures back up to

Clouds will begin to increase again late in the day ahead of a
quick-moving surface low/midlevel shortwave dropping across the
Great Lakes. The best chance for showers late Sunday and Sunday
night will lie north of Pittsburgh where the best low-level
convergence will be seen, with some isolated activity possible
along the ridges. The low will drag a front across Sunday night,
which will bring temperatures back to below normal. Monday will
feature lingering clouds in northwest flow, most numerous across
the north, where a few isolated showers may continue. Skies should
begin to clear Monday night as surface high pressure and upper
ridging return.


Long term /Tuesday through Friday/...
continued ridging aloft will maintain dry weather into Wednesday.A
digging trough will cross the Mississippi River and begin to
impact our region during the late week period, with our next
decent chance of rain. The models differ on the fate of this
trough at the end of next week, lending much uncertainty to
precipitation chances and amounts. Temperatures will be near or
just a bit below climatology through the period.


Aviation /16z Saturday through Wednesday/...
MVFR to low VFR conditions are expected through much of today with
an upper low in close proximity and with cool northwest flow. The
stratocu layer should lift to VFR for much of the area through the
afternoon as mixing lifts the cloud bases, though areas north of I
80 should remain MVFR until Evening. Lake enhanced showers should
also persist through much of the day.

A tight pressure gradient should result in west-northwest winds gusting to
25kt at times.

Outlook /Sunday through Wednesday/...
restrictions are possible with a Sunday night/Monday cold front.


Pbz watches/warnings/advisories...



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