467 
fxus61 kctp 051927 
afdctp 


Area forecast discussion 
National Weather Service State College PA 
327 PM EDT Sat Jul 5 2008 


Synopsis... 
a wavy front just south of the Mason-Dixon line...will slowly 
weaken and lift north later in the weekend...leading to muggy 
unsettled conditions that will last into at least early next week. 


&& 


Near term /until 6 am Sunday morning/... 
earlier slow moving area of showers has broken up and the remnants 
have appeared to settle off to the south and east. With some 
heating more convection is popping from SW Bedford County east to 
near mui. Extensive cloud-cover is limiting heating so little more 
than a localized downpour is expected...mainly over the area south 
of I-80. The main issue will be if cells become anchored again 
like they did for a time this morning from jst eastward. Some 1-2 
inch amounts could occur if they do. Moisture isn't especially 
deep as displayed by precipitable water anomalies displaced offshore...but low 
topped showers that fell near gages showed some very efficient 
rain making going on. Think activity will be strongly diurnal and 
drop off after heating wanes this evening. 


Best weather overnight will be over the north where skies will 
likely scattered out. Confined mention of showers to the far southeastern 
counties...closest to the persistent low level convergence 
associated with the weak boundary and inverted trough. However the 
weak east flow will probably allow the clouds to reestablish so a 
rather muggy cloudy night is likely over much of the southeastern 1/2 or 
so of the forecast area. Overnight lows will average very near climatology. 


&& 


Short term /6 am Sunday morning through 6 PM Sunday/... 
weak upper low is forecast to close off just to our west...increasing 
the moisture and instability. Ensembles show convective available potential energy likely to 
exceed 1200j Sun afternoon so a more active day should be expected 
as storms pop off with day time heating. Deepest moisture still 
east of the area...but latest sref/gefs show anom precipitable waters  starting 
to creep back over the area...covering southeastern PA by day's end in the 
sref...and into central PA in the gefs. Looks like a muggy warm 
unsettled day. Shear doesn't look overly impressive so localized 
Gully washers will probably be the big threat. 850 temperatures in the 
14-16c range and plenty of cloud cover should equate to highs 
within a few degrees of 80...very near climatology for early July. 


&& 


Long term /Sunday night through Saturday/... 
zonal flow is forecast over the Continental U.S. Through the period with a 
strong jet riding the northern border states and weak upper ridging 
with little flow over the southern U.S. 


The jet is forecast to buckle a bit and bring a cold front through the 
NE on Wednesday. Warm and humid conditions will precede the Wednesday 
frontal passage along with the daily threat of showers and thunderstorms. 
Maximum temperatures are forecast to be around 5 degrees above normal Tuesday 
and Wednesday. 


The front will bring a brief cool down...with near normal or 
slightly below normal temperatures forecast for Thursday and 
Friday. Hot weather will return for next weekend as heights rise 
and the 588dm height contour pushes north into PA. 


&& 


Aviation /19z Saturday through Thursday/... 
weak front is hanging just south of the PA border...pooling just 
enough moisture to cause a rather dreary day over many of the 
southern terminals. Also a few showers/storms to contend 
with...these should die off toward sunset. The worst conditions 
overnight into early Sunday will be from about I-80 southward as 
some redevelopment of reduced visibilities and ceilings will 
become likely with the persistent weak easterly flow. 


Sunday will start off MVFR over most of the area before burning 
off to a hazy warm and humid day with scattered-numerous afternoon- 
evening showers and thunderstorms. Expect widely variable 
conditions with these...depending on who gets hit and gets missed. 
This will then play into the forecast for overnight Sunday into 
Monday. Fog will become an issue wherever showers manage to form 
Sunday afternoon and evening. 


Pattern looks typically Summer-like Monday into perhaps Wednesday as 
broad west-southwest flow dominates with warm humid conditions. This would 
favor afternoon and evening convection along with possible fog 
problems overnight wherever the rain manages to fall. 


A frontal boundary should bring some drier air and improving conds 
for middle week. 


&& 


Ctp watches/warnings/advisories... 
none. 


&& 


$$ 
Synopsis...lacorte 
near term...lacorte 
short term...lacorte 
long term...gartner/Martin 
aviation...lacorte