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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KCTP 182233
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
633 PM EDT Mon Sep 18 2017

.SYNOPSIS...
A persistent ridge of high pressure at the surface and aloft
will maintain fair, warm and generally dry weather during the
entire upcoming week, and likely through the weekend as well.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
Satellite shows the fog and low clouds have mixed out out over
all but my far sern counties where the marine layer is deeper
and slower to dry/mix out.

Radar shows a few small showers popping up over my western zones
where higher PWATs and heating on the ridges are forcing some
local convection. There is a pretty good wedge of dry air around
700mb so showers will remain squat, with most areas remaining
dry.

The overnight will be a carbon copy from the department of
redundancy department with daytime showers fading early followed
by fair skies then followed by developing valley fog and low
clouds.

Lows in the upper 50s to lower 60s will average around 10 deg
above normal.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...
Tuesday will once again begin with the locally dense valley
fog, burning off to a partly-mostly sunny afternoon as the upper
ridge axis continues to reside right over central PA.

The western extent of the outer bands of showers associated
with Hurricane Jose that will be east of the Delmarva coast will
flirt with SERN zones where I painted chance POPs in the
afternoon. With expected light rain and thicker cloud cover,
temps will likely be suppressed a bit across that region of the
CWA compared to recent days. Max temps elsewhere will continue
to run 6-10F above normal for mid September.

&&

.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
For much of this period, a 500 hPa ridge will dominate our
weather. As Jose moves away to the NE, heights will rise and
this should further dry us out for the second half of this
week. The GEFS forecasts a closed 5880 m ridge over us with
near +2 sigma above normal heights by  Friday and Saturday
which will translate to well above normal temps. Enjoy!

&&

.AVIATION /22Z MONDAY THROUGH SATURDAY/...
-- Changed Discussion --
At 22Z, just a small patch of MVFR ceilings remain in vicinity
of KMDT. Satellite trends and near term model output suggests
this patch of stratocu will break up by around 00Z.

The main concern overnight remains the likelihood of low cigs
and fog developing across the central part of the state in
response to radiational cooling under high pressure ridge. LAMP
and SREF guidance support the idea of IFR/LIFR conditions late
tonight over the western airfields, including
KBFD/KJST/KUNV/KAOO. Further south and east the confidence in
significant reductions is lower due to the possibility of a
persistent northeast breeze, which could preclude fog/low cloud
development. KLNS currently appears the least likely to
experience significant reductions with the odds of IFR just
below 50 pct.

Improving conditions are expected during late morning, as any
low clouds/fog begin to lift. Model data and climatology support
a high confidence of widespread VFR conditions by Tuesday
afternoon.

.Outlook...

Wed-Sat...AM restrictions in low clouds/fog; otherwise VFR with
no sig wx.
-- End Changed Discussion --

&&

.CTP WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$
SYNOPSIS...La Corte
NEAR TERM...La Corte
SHORT TERM...La Corte
LONG TERM...Lambert/Gartner
AVIATION...Fitzgerald/La Corte