Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

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160
FXUS61 KPHI 220018
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
818 PM EDT Sat Sep 21 2024

.SYNOPSIS...
Low pressure continues to meander off the East Coast. It will
drift to the south and east early during the upcoming work week.
Meanwhile, high pressure is extended over the region but will slowly
move offshore and eastward Sunday into Monday. A slow moving cold
front then approaches from the west, and low pressure may develop
on that front and impact the region late next week.

&&

.NEAR TERM /THROUGH SUNDAY/...
High pressure continues over the region nestled in between a
meandering low offshore and a system to the northwest over interior
Canada. A weak shortwave is presently moving into north/central
PA and resulting in scattered showers and a few tstms. The best
chance of showers across our area extend south-southeast from
the southern Poconos down into Delmarva. Chances really come
down across central and northern NJ. Present radar trends seem
to match up well, but the showers farthest N/W seem to be
lasting longer while closer to Berks county and south, the
showers are widely scattered at best. A few adjustments to the
POPs/Wx have been made to match the trends. Lows tonight will
range from the low/mid 50s across the north to the mid 60s for
SE NJ and Delmarva. Areas fog may occur if the NW/W areas
receive any rains overnight. The fog will be more patchy
elsewhere.

A mid-level trough will be along the Mid-Atlantic Coast tomorrow
morning. As a result, we`re carrying a small chance of showers
across the south. Any shower activity will taper off by midday.
Clouds will be on decrease tomorrow afternoon. Afternoon highs will
be in the upper 60s to mid 70s.

&&

.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
A wedge of high pressure will continue to be over the Northeast
and Mid-Atlantic Sunday night into Monday before lifting away
Monday night. A slow-moving cold front then begins to approach
the region late Monday but may stall out to our west as the
initial upper level low becomes cutoff. However, shortwave
energy diving out ahead of the front may trigger some showers
late Monday through Tuesday. PoPs will mostly be slight chance
from late Monday through midnight or so Monday night, but then
PoPs increase to chance after midnight Monday night before
decreasing once again by later Tuesday. The highest PoPs are
focused on the most western portion of the region which will be
closest to the stalling front. As has mostly been the case, QPF
will be light.

Lows Sunday night and Monday night will generally be in the
50s, though around 60 at the immediate coasts due to the warmer
ocean temperatures. Highs on Monday will once again be in the
low to mid 70s with temperatures right around 70 for Tuesday.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
The Long Term period will feature a prolonged period of
unsettled weather.

By Tuesday night, a new upper-level trough begins to push
eastward across the Great Lakes towards the Northeastern US
while a cutoff low lingers over the southern Plains. This
movement in the upper-levels looks to help move the surface low
pressure along and drag the front into the local area Wednesday
into Thursday. With the front approaching and increasing
shortwave energy, showers look to become more widespread in this
time period. This would bring more in the way of rainfall to
the area from Tuesday night through Wednesday night period.
Will follow NBM and go with likely PoPs during that time.
However, there remains inconsistencies among the models, so
this may change.

The front may not fully clear the region until Friday or so, as
another cutoff upper-level low may develop, and unsettled
weather may remain in place until then as a result.

Temperatures will be at or a few degrees below normal during
this time.

&&

.AVIATION /00Z SUNDAY THROUGH THURSDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY and surrounding areas.

Tonight...Mainly VFR. There`s a chance of showers north/west of
I95. This could result in MVFR conditions at KABE and more so
at KRDG. Patchy fog possible, but not mentioned in the TAFs.
Moderate confidence.

Sunday...Mainly VFR. There could be some MVFR to start at KRDG.
There`s also a very small chance of morning showers at KILG, but
I did not mention in the TAF. Moderate confidence.

Outlook...

Sunday night through Monday...Primarily VFR conditions, though
sub- VFR VSBYs possible in fog Sunday night/Monday morning.

Monday night through Tuesday...VFR, though MVFR or IFR possible
in SHRA.

Tuesday night through Thursday...Periods of MVFR or IFR in
SHRA.

&&

.MARINE...
Small Craft Advisories remain in effect for the ocean waters through
tomorrow, primarily for 4 to 6 ft seas. NE winds will generally
average 15 to 20 kts.

Sub-SCA conditions for Delaware Bay. Mainly NE winds around 10 to 15
kts.

Outlook...

Sunday night through Monday...SCA in effect for the ocean
waters, mainly for elevated seas.

Monday night through Thursday...SCA may be needed for elevated
seas into the middle of next week.

Rip currents...

There is a HIGH risk for the development of dangerous and life
threatening rip currents at the Jersey Shore and at Delaware Beaches
through Monday. NE winds will range from 10 to 20 mph with gusts up
to 25 mph along with 3 to 6 ft breaking waves.

Rip currents occur often in the vicinities of jetties and piers and
the speed of the currents are generally maximized at low tides.

For specific beach forecasts, visit weather.gov/beach/phi

&&

.TIDES/COASTAL FLOODING...
A prolonged period of onshore flow has resulted in, and will
continue to result in, a piling up of water along the coasts with
this water unable to drain within tidal waterways. At least minor
tidal flooding is expected for the next several high tide cycles for
most portions of the area. Moderate tidal flooding could possibly
occur again for some portions of the area Sunday.

Changes to headlines:

Coastal Flood Warning has been dropped for most of the Atlantic
coast and Delaware Bay and replaced with advisories covering through
the Monday morning/afternoon high tide cycle. However, will keep the
Coastal Flood Warning for Cape May and Cumberland counties in New
Jersey and for Kent County in Delaware through the Sunday
morning/afternoon high tide cycle. These areas may experience some
moderate coastal flooding once again on Sunday. Thereafter, a
Coastal Flood Advisory is in effect for these areas as is for the
rest of the Atlantic coast and Delaware Bay.

For the tidal Delaware River, Coastal Flood Advisories are in effect
through the late Monday high tide cycle for minor coastal flooding.

For the northeastern shore of Maryland, it looks like minor coastal
flooding will begin with the high tide cycle tonight.
This also now includes Kent county, Maryland. Will go ahead and
issue Coastal Flood Advisories through the Monday evening high tide
cycles; it looks like it will be the evening high tide cycles that
will be most impacted by minor coastal flooding.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...Coastal Flood Advisory until 10 PM EDT Monday for PAZ070-071-
     106.
NJ...Coastal Flood Advisory until 6 PM EDT Monday for NJZ016.
     Coastal Flood Warning until 5 PM EDT Sunday for NJZ021-023-024.
     Coastal Flood Advisory from 5 PM Sunday to 5 PM EDT Monday for
     NJZ021-023-024.
     Coastal Flood Advisory until 5 PM EDT Monday for NJZ012>014-
     020-022-025>027.
     High Risk for Rip Currents through Monday evening for NJZ014-
     024>026.
     Coastal Flood Advisory until 10 PM EDT Monday for NJZ017>019.
DE...Coastal Flood Advisory until 6 PM EDT Monday for DEZ001.
     Coastal Flood Warning until 5 PM EDT Sunday for DEZ002.
     Coastal Flood Advisory from 5 PM Sunday to 5 PM EDT Monday for
     DEZ002.
     Coastal Flood Advisory until 5 PM EDT Monday for DEZ003-004.
     High Risk for Rip Currents through Monday evening for DEZ004.
MD...Coastal Flood Advisory until 5 AM EDT Tuesday for MDZ012.
     Coastal Flood Advisory until 2 AM EDT Tuesday for MDZ015-019-
     020.
MARINE...Small Craft Advisory until 6 PM EDT Monday for ANZ450>455.

&&

$$

SYNOPSIS...AKL/MPS
NEAR TERM...Kruzdlo/po
SHORT TERM...AKL/MPS
LONG TERM...AKL/MPS
AVIATION...AKL/Kruzdlo/po
MARINE...AKL/Kruzdlo/Wunderlin
TIDES/COASTAL FLOODING...Wunderlin