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000
FXUS61 KCTP 212210
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
610 PM EDT Mon Aug 21 2017

.SYNOPSIS...
High pressure moving off the Mid Atlantic coast will bring a
warm and increasingly humid southerly flow to the region into
Tuesday. A strong cold front will move through the region late
Tuesday and Tuesday night. Cooler and drier conditions will
return for the second half of the week.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
Turn around bright eyes to see the partial eclipse of the sun.
But use special glasses or a box. Do not look directly at the
sun.

Radar shows high clouds over central PA due to thunderstorms to
the west. Anvil tops are obscuring the sky in central areas.
GOES-16 shows cloud streets in the northwest and southeast. Many
should have good viewing in scattered to broken clouds.

Warm afternoon and scattered showers and thunderstorms about.

Chance rain diminishes in evening with areas patchy fog and
humid.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...
Warm humid day Tuesday. Some issues with the timing of the
showers in CAM verse none convective allowing models. Most
guidance suggest rain likely and some strong to severe storms
possible in the late afternoon/evening.

Timing in some CAMS implies earlier convection than non-
convective models.

The front should bring in much cooler weather Tuesday
night. But ahead of it Tuesday will be a warm humid day with a
good chance of showers and thunderstorms.

&&

.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
A strong cold frontal passage late Tuesday (NW PA)/Tuesday
night (SE PA) will be followed by a extended period of early
autumn-like weather for Wednesday into the upcoming weekend as
an anomalously deep sfc low/upper trough slides east across
southeastern Canada.

Daytime high temps will be about 5-7 Deg F below normal across
the Western Mtns on Wednesday, though still just slightly below
normal across the SE zones prior to the arrival of the
deeper/colder air for the latter part of the week.

GEFS mean 850 mb temps will dip about 2-3 deg C in all locations
for Thursday-Sunday, leading to max temps averaging 5-10 F
below normal (with min temp departures about 10-13F below
normal Friday-Sunday) as a large Canadian High Pressure area
pushes SE across the Glakes Region and becomes centered over the
NE states.

Lows Fri/Sat/Sun mornings with high centered overhead, will be
dipping into the l-m 40s over the Northern Mountains (and
deeper valleys of the Central Mountains) and solidly into the
50s elsewhere. Some of the perennial cold spots near and to the
east of KBFD could see readings of 38 or 39F.

&&

.AVIATION /22Z MONDAY THROUGH SATURDAY/...
Scattered to isolated showers and thunderstorms across Central
Pennsylvania at 22z. Most are exiting the Middle and Lower
Susquehanna Valley areas at this time, with a few more north of
KUNV.

Mainly VFR conditions for the rest of the day, except for
isolated restrictions in TSRA through about 01z.

Overnight, expect areas of MVFR fog to develop, with isolated
spots of IFR visibilities and ceilings.

Morning fog gives way to VFR conditions Tuesday, but widespread
TSRA expected during the afternoon and evening.

.OUTLOOK...

Tue...Patchy AM fog. Afternoon/evening TSRA impacts possible.
Wed...AM low cigs BFD/JST, otherwise VFR.
Thu-Sat...No sig wx expected.

&&

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

&&

$$
SYNOPSIS...La Corte
NEAR TERM...Grumm
SHORT TERM...Grumm/La Corte
LONG TERM...La Corte/Lambert
AVIATION...Grumm/Jung