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Area forecast discussion 
National Weather Service Pittsburgh PA
1130 am EDT sun Aug 30 2015

weak low pressure will bring shower chances today across the
upper Ohio Valley region. Warm and humid conditions expected
through the upcoming week.


Near term /through tonight/...
shower/isolated thunderstorm chances are expected to continue
through this evening with the approach of a slow moving upper
trough...though observed morning soundings show warming middle
levels should help limit instability and precipitation coverage.
Temperatures a few degrees above average are expected using the
latest GFS MOS.


Short term /Monday through Wednesday/...
a vorticity lobe will lift from the southern Appalachians towards
the midatlantic coast on Monday. The southern portion of the County Warning Area
will be skimmed by this. Moisture and instability will be barely
sufficient for slight chance probability of precipitation from pit on south. Proximity to
vorticity lobe plus terrain effects may allow for a bit better
coverage along the southeastern ridges. Departure of disturbance
plus loss of heating will end precipitation chances by 00z

Thereafter...ridging will take control of the eastern part of the
country and hold on for an extended period. Midlevel capping
appears more likely on Tuesday...and for now have only kept slight
chance probability of precipitation along the ridges. For Wednesday...a weak shortwave
over the Ohio Valley...embedded in the general ridging
pattern...may allow capping to be overcome sufficiently for
isolated convection. Each nighttime period should be mostly dry.

Temperatures will of course be above normal in this pattern.
Generally blended mosguide with previous values for the forecast.
Would expect some readings at or just over the 90 degree level by
Wednesday afternoon.


Long term /Wednesday night through Saturday/...
no changes to the overall pattern are expected...with the eastern
ridge holding firm. With the ridge axis still to the west on areawide slight chance still looks appropriate. The
sprawling upper high will drift eastward with time though...such
that the ridges would be favored mainly for diurnal activity for
Friday and Saturday. By Sunday...with the center of the ridge just
to the improved moisture feed may support activity
areawide once again. Little organization is foreseen throughout
the extended period...with overall precipitation totals remaining
fairly low. Above normal temperatures in the 80s to around 90 will
be featured each day.


Aviation /16z Sunday through Thursday/...
continued general VFR ceilings through the taf period with only
scattered showers at best with weak upper support and shallow
moisture. Additional restrictions are possible with fog
development in the pre-dawn hours Monday. Winds will be light
mainly from the west.

Outlook...Monday through Thursday...
general VFR except for possible patchy morning fog the remainder
of the week.


Pbz watches/warnings/advisories...



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