.AVIATION /20Z THURSDAY THROUGH TUESDAY/...
Late afternoon update.

Main change was to slow down convection to the west by about
2 hours. Showers and storms are moving from about 250 at 30
knots, so will take a bit to get to UNV and AOO at points 
eastward. Will adjust more for the 00Z package, mainly for
activity later on Friday.

Earlier discussion below.

VFR regionwide for the Central Mtns and Susq Valley through 20Z,
with an earlier onset time of SHRA/TSRA impacting the NW Mtns 
and Laurel Highlands with brief restrictions. 

Multicell clusters & quasi-linear segments are the favored form
of convection given marginally favorable deep-layer shear 
(20-30 kts), along with threat for gusty to perhaps severe- 
level winds given steep low- level lapse rates (8-9 C/km) and 
moderate-high DCAPE (1000-1250 J/kg). 

Visibility restrictions will be likely in these storms, 
especially given high moisture content (PWATs around 1.5") which
will bring heavy rain in storms. Convective activity across 
central PA will downtrend after 00Z as the shortwave progresses 
east of our area, with patchy fog possible once again Thursday 
night given moist environment & breaks in cloud cover.

Outlook...

Friday...Some generally brief restrictions expected as an 
approaching CFROPA brings a few lines of -TSRA.

Saturday...Mainly VFR.

Sunday...VFR favored early, with restrictions possible as FROPA
brings chance of -SHRA/-TSRA later in the day.

Monday...Additional scattered -SHRA and associated restrictions
possible.

Tuesday...Still a slight chance of showers and storms.

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