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000
FXUS61 KPHI 250123
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
923 PM EDT Mon Sep 24 2018

.SYNOPSIS...
A stationary front to the south will slowly begin to move northward
in several waves as a strong area of high pressure to the north
stubbornly moves to the east. A cold front will quickly follow the
warm front`s passage Wednesday night. Dry weather should prevail
through the early part of the weekend before another cold front
moves toward the region Sunday.

&&

.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
Steadier and more widespread precip lies over central and
western PA and is moving east. That rain should fill in
overnight. Rain could be moderate to heavy at times for some
ares, especially N/W of I-95. Onshore low-level east flow this
evening should gradually veer around to the southeast towards
morning. This will result in warmer and more humid air advecting
into the region. Temps are not expected to fall much overnight
and areas of fog are likely to develop.

&&

.SHORT TERM /6 AM TUESDAY MORNING THROUGH 6 PM TUESDAY/...
Winds will continue to veer from SE to S on Tuesday as warmer
and more humid air continues to advect into the region. Forecast
PoPs generally decrease from south to north during the day as
the better lift shifts north of NJ. Precip will likely become
more showery in nature as well. Max temps will be noticeably
warmer than today, especially S/E of PHL.

&&

.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
Tuesday night through Wednesday...A brief break in the weather may
occur ahead of a cold front arriving on Wednesday. Guidance shows
the front crossing the region during the afternoon/evening, and this
timing will increase the potential for thunderstorm development.
Southerly flow ahead of the front will increase moisture across the
region and PWATs will start to rise near 2 inches, leading to
efficient rainfall within any shower or storm that develops.
Although it looks like Wednesday will be a fairly cloudy day, any
breaks in the clouds will help increase surface instability and help
in the development of thunderstorms. SPC has placed a good portion
of our area in a slight risk for severe thunderstorms. Should the
front arrive later, the convective potential will be less so it
bears some watching.

As the front pushes to the east Wednesday evening, showers and
thunderstorms will decrease in coverage from west to east. While
some lingering showers may remain into the overnight, we should
start to see some drying out occur in the developing northwest flow.

Thursday...The cold front pushes well south of our area, stalling
closer to the Carolinas. High pressure will build across the
northern Mid-Atlantic and into New England on Thursday. As the high
slides across to our north, we should see the northwest flow turn
more to the north or northeast Thursday. If the high can build a
little further south, we may be able to squeeze out a dry day across
the region. However, with easterly flow developing, we could see
some scattered showers develop. Therefore, continue to mention a
chance for some showers in the forecast.

Friday through Monday...High pressure will start to build across the
eastern US for Friday through the weekend. Expect skies to start
clearing out with plenty of sunshine across our area. Overall, this
weekend looks to be very nice for fall with temps remaining in the
70s during the day and dropping into the 50s to lower 60s overnight.

A cold front may start to approach from the west late in the weekend
but the models show varying solutions at this time. The front may
hold off until the start of the new week, keeping us dry into
Monday.

&&

.AVIATION /01Z TUESDAY THROUGH SATURDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY and surrounding areas.

CIGs will continue to lower to MVFR, and eventually IFR
overnight. Fog may develop overnight and persist for several
hours after sunrise Tuesday. Conditions Tuesday morning may be
slow to improve. Winds will continue out of the east tonight but
will veer to the SE Tuesday morning and south in the afternoon.
This veering trend will be slower to occur at ABE/RDG.

OUTLOOK...

Tuesday night...Mainly VFR conditions. Scattered showers with sub-
VFR conditions possible. Southeast winds around 5 to 10 knots.

Wednesday...Mainly VFR conditions expected. Conditions will
deteriorate to MVFR/IFR in showers and thunderstorms as a cold front
crosses the terminals.  South to southwest winds around 10 knots
will become northwest around 10 knots behind the front.

Thursday...Mainly VFR conditions expected. Scattered showers
with sub-VFR conditions possible. east or northeast winds around
10 knots or less.

Friday...Mainly VFR conditions expected. Light winds.

&&

.MARINE...
SCA conditions will continue on Delaware Bay through tonight
and on the ocean waters through Tuesday and beyond. Winds
should diminish on Tuesday as the veer from east to southeast,
however, seas will remain elevated on the ocean. Visibility will
be limited in areas of rain and fog tonight, continuing into
Tuesday morning.

OUTLOOK...

Tuesday night through Thursday...The Small Craft Advisory has been
extended through Wednesday on the ocean waters of New Jersey and
Delaware. Seas will be around 5 to 7 feet and should start to
diminish some on Wednesday. However, seas will likely remain above 5
feet through Thursday and the Small Craft Advisory will likely need
to be extended. Winds may gust around 25 knots at times on Thursday.

Friday...Sub-SCA conditions are expected on the area waters.

Rip Currents...

There is a moderate risk for the development of dangerous rip
currents at NJ and DE ocean beaches on Tuesday. Winds will shift
from the east tonight to more of a southerly flow by afternoon.
Tides will also be enhanced by the full moon.

&&

.TIDES/COASTAL FLOODING...
Coastal Flood Advisory remains in effect for the evening high
tide cycle tonight for the ocean waters, back bays, and lower
Delaware Bay, and has been extended to include the following
high tide cycle. A Coastal Flood Advisory is now in effect for
the tidal Delaware River, as well as upper Delaware Bay for the
next two high tide cycles as well.

The astronomical tides will be high due to the full Harvest
Moon. The onshore flow is forecast to continue tonight before
veering to the south on Tuesday, from south to north.

&&

.CLIMATE...
On Sunday, the Philadelphia International Airport (PHL)
received 0.70 inches of rain, which brought the yearly
precipitation total up to 41.58 inches. The normal rainfall for
the entire calendar year at PHL is 41.53, which means we are
already above normal for the year, with 99 days left to go. PHL
joins the Atlantic City Airport (ACY), Mount Pocono (MPO), and
Reading (RDG) as sites that have already reached their average
annual precipitation. Both Wilmington (ILG) and Allentown (ABE)
could reach their average annual precipitation this week, as
those sites are within 1.08 and 0.90 inches respectively of that
mark.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...Coastal Flood Advisory until 5 PM EDT Tuesday for PAZ070-071-
     106.
NJ...Coastal Flood Advisory until 2 PM EDT Tuesday for NJZ012>014-
     020>027.
     Coastal Flood Advisory until 2 PM EDT Tuesday for NJZ016.
     Coastal Flood Advisory until 5 PM EDT Tuesday for NJZ015-
     017>019.
DE...Coastal Flood Advisory until 2 PM EDT Tuesday for DEZ002>004.
     Coastal Flood Advisory until 2 PM EDT Tuesday for DEZ001.
MD...None.
MARINE...Small Craft Advisory until 6 PM EDT Wednesday for ANZ450>455.
     Small Craft Advisory until 6 AM EDT Tuesday for ANZ430-431.

&&

$$
Synopsis...Davis
Near Term...AMC/MPS
Short Term...AMC
Long Term...Meola
Aviation...AMC/Meola/MPS
Marine...AMC/Meola/MPS
Tides/Coastal Flooding...MPS
Climate...