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Area forecast discussion 
National Weather Service State College PA
1054 am EDT Thursday Aug 25 2016

Synopsis...
a seasonally warm and humid late-Summer weather pattern will
continue across central Pennsylvania into next week. Scattered
thunderstorms with strong wind gusts are possible in the northwest
alleghenies later this afternoon into the evening.

&&

Near term /through tonight/...
showers decreasing in coverage and intensity. Used a blend of
convective- allowing models (cams) for the remainder of the near
term period which resulted in Max pops over the northwest alleghenies
during the late afternoon into early evening. This area is
included in the marginal severe tstom risk outlook from Storm Prediction Center. In the
absence of large-scale forcing for synoptic lift/neutral- to-weak
height rises, diurnal heating - which may be delayed due to cloud
cover early in the day - and small scale shortwave impulses will
play a key role in renewed convective development. This of course
adds some degree of uncertainty into the forecast. Assuming this
occurs as is generally depicted by a consensus of cam guidance, a
few strong to locally damaging wind gusts will be possible mainly
over northwest PA within corridor of high precipitable water and 30-40kt mid-level
flow. Expect any storms to weaken after dark given loss of
instability, with decreasing coverage into the overnight hours.

&&

Short term /Friday through Friday night/...
there is increasing confidence in a dry Friday, as all models now
push dying cold front southeast of the region by 12z Sat. Main
effect of fropa will be to lower humidity, as gefs 8h temps remain
above normal behind front, likely supporting Max temps from the
low 80s across the NW mtns, to around 90f in the susq valley.
Model soundings suggest Friday could begin mcldy over the
alleghenies, but any Post-frontal stratocu should mix out to
msunny skies everywhere by aftn.

Sfc high will build over the region Friday night, resulting in a
fair and mild night. Will have to watch for the possibility of
patchy valley fog over the northern mtns late.

&&

Long term /Saturday through Wednesday/...
center of subtropical ridge over the southeast conus is progged
by all models to migrate northeast to the mid Atlantic by this
weekend. Lg scale subsidence and warm temps aloft assoc with this
feature should translate to hot and humid conds with little
chance of rain across most of central PA. However, a shortwave
tracking across southern Ontario could trigger sct late day
shra/tsra on Sunday across northwest PA.

00z naefs and ecens both strongly favor a continuation of well
abv normal temps into next week with mean 8h temps still btwn
18-20c. Weakening upper ridge is progged by mdls to slip southward
a bit, placing PA within a more favorable regime for diurnal
convection on northern edge of upper ridge within plume of
anomalous precipitable waters . High humidity and warm nights appear likely into
next week, esp across southern PA, where anomalous pwats on the
order of +1sd indicated in the 00z gefs.

&&

Aviation /15z Thursday through Monday/...
line of showers/storms over eastern Ohio should gradually weaken as
it shifts ewd across the western-central airspace between 09-12z.
Confidence is low in the band holding together into zny sector.
Agree with guidance bringing a short period of low MVFR to IFR
cigs into kbfd/kjst behind the line given moist low level flow
ascending the higher terrain. Conditions trend to VFR into mid-day
with focus shifting to potential thunderstorm impacts for the
afternoon/evening. Will wait to examine the latest cam guidance
before adding mention of thunder with the 25/12z scheduled tafs.
Scattered showers remain possible tonight with some restrictions
likely heading into Friday morning.

Outlook...

Fri...a.M. Restrictions possible; becoming VFR. Isold thunderstorms
possible southern 1/4 airspace in the afternoon.

Sat...patchy a.M. Fog. Otherwise no sig wx expected.

Sun...isold thunderstorms possible western 1/3 airspace in the
afternoon.

Mon...isold-sct thunderstorms possible.

&&

Ctp watches/warnings/advisories...
none.

&&

$$
Synopsis...steinbugl
near term...Ross/Fitzgerald
short term...Fitzgerald
long term...Fitzgerald
aviation...steinbugl

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