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341
FXUS61 KCTP 200711
AFDCTP

Area Forecast Discussion
National Weather Service State College PA
311 AM EDT Mon May 20 2024

.SYNOPSIS...
High pressure is building into the region. Predominantly dry
conditions, light winds and warmer temperatures are expected to
hold into the middle of the upcoming week. A storm system should
arrive later Wednesday into Thursday bringing the next chance
of showers and thunderstorms to the area.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
Earlier cu has all but dissipated, leaving mainly clear skies
across Central PA. Surprisingly, BFD has already seen it`s vsby
drop below 1 mile, so fog is already beginning to form in a few
favored locations.

A light easterly flow in the llvls persists and could once
again bring in Atlantic moisture overnight. Expect stratus to
return to the ern half (or more) of the CWA. There could also be
fog around overnight, but lack of rainfall during the day and
the potential for the development of low clouds may work against
it. Dewpoints should remain in the 50s, however, and min temps
should dip to near the dewpoint.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM TUESDAY/...
As with Sunday AM, any low clouds will have to burn away with
the mid-May sun. However, earlier dissipation of the stratus
should help temps Monday aftn rise a few to several degrees
warmer than Sunday`s maxes.

There could be just enough instability across the nrn tier of
counties in the aftn to pop a lonesome SHRA/TSRA. Left PoPs in
the 20-30pct range for now. The support aloft is tough to find
except for perhaps a short wave trough rolling over the upper
Great Lakes.

Mon night looks similar to the last few nights, with perhaps
less of a reprisal of the nighttime stratus. There could still
be some fog, but we`ve only mentioned patchy fog for the time
being. Mins will probably be a bit milder than Mon AM as well.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
Tuesday and Wednesday will be very warm days with south to
southwesterly flow and plentiful sunshine. Expect highs to reach
the 80s both days, and some valley spots could even touch 90
degrees on Wed aftn.

Surface low pressure is progged to track north of the Great
Lakes and well north of PA during the mid to late week period.
The associated cold front will cross Pennsylvania Wed night or
early Thurs, accompanied by scattered showers and thunderstorms.

After the front moves through, uncertainty remains as to how
far to our south it will settle before stalling. This could keep
a chc of showers across at least southern PA through the end of
the week.

There is considerable uncertainty heading into next weekend,
but it appears that there is a chc that our weather could
remain unsettled.

&&

.AVIATION /07Z MONDAY THROUGH FRIDAY/...
-- Changed Discussion --
Valley fog has developed across the northwest 2/3 of the
airspace resulting in localized visibility at or below airfield
minimums (1/2-1/4SM). Max IFR fog confidence is focused over
the south central terminals AOO/JST/UNV based on obs trends and
IR satellite imagery. Expect VFR/IFR fluctuations at BFD. MVFR
to IFR stratus layer expanding over southeast PA and will impact
LNS/MDT and perhaps IPT-which may also experience restrictions
in fog through the predawn hours.

Valley fog will dissipate quickly in the morning, but the low
clouds in the southeast airspace will be slower to break. MVFR
ceilings could remain in place across the Lower Susquehanna
Valley through 18Z. Widespread VFR conditions are expected
once fog/low cloud erode with light winds. Some guidance shows
the potential for a isolated thunderstorm across the northern
tier later this afternoon, but confidence/coverage remains too
low to include mention in the TAFs.

Outlook...

Tue...VFR/no sig wx.

Wed-Thu...Chance of t-storms.

Fri...Mainly VFR, slight chance of showers.
-- End Changed Discussion --

&&

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

&&

$$

SYNOPSIS...Dangelo/Evanego
NEAR TERM...Evanego
SHORT TERM...Dangelo/Evanego
LONG TERM...Evanego/Bowen
AVIATION...Steinbugl/Bauco