053
FXUS61 KPHI 151847
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
247 PM EDT Mon Sep 15 2025

.SYNOPSIS...
A coastal low initially located off of the Carolinas will track
northeastward towards the area through mid-week. Wednesday into
Thursday, the low is expected to weaken substantially as it
makes its closest approach. A cold front moves through Friday,
with high pressure building southeastward into the region
through the weekend.

&&

.NEAR TERM /THROUGH TUESDAY NIGHT/...
High pressure centered over the Province of Quebec builds east
tonight and then will be over the Canadian Maritimes Tuesday
night. Meanwhile, nearly vertically stacked low pressure off the
Carolina coast will retrograde to the west and will move into
eastern North Carolina and eastern Virgina Tuesday morning. This
system will meander over the Mid-Atlantic through Tuesday
night.

In terms of sensible weather, clouds increase and lower tonight
through Tuesday morning. Some rain bands may lift into Delmarva
and southern New Jersey by daybreak Tuesday, but most of the
rain will hold off until Tuesday afternoon and evening. The
heaviest rain will impact Delmarva and southeast New Jersey,
where 1/2 inch to as much as 1 inch of rain is possible in these
areas, and up to 1/4 inch of rain will spread as far west as
the I-95 corridor. Much lighter amounts are possible across the
southern Poconos, Lehigh Valley, and northern New Jersey.

Starting Tuesday afternoon and continuing into Tuesday night,
shortwaves associated with the closed upper low over the Mid-
Atlantic will lift towards the southern areas, and this may
provide enough instability for some afternoon and evening
thunderstorms. Not expecting severe weather, but some brief wind
gusts and brief, locally heavy rain will be possible.

East to northeast winds will generally range from 5 to 10 mph
tonight, then will increase to 10 to 15 mph with 20 to 25 mph
gusts for most areas, though winds will be stronger along the
Atlantic coasts, generally ranging from 15 to 20 mph with 25 to
35 mph gusts. Winds should remain below Wind Advisory criteria,
though a brief gust to 45 mph is possible in any convection.
Winds diminish Tuesday night.

Lows tonight and Tuesday night will generally be in the upper
50s to low 60s. Onshore flow keeps coastal areas quite chilly,
with highs in the low 70s across eastern New Jersey and
Delmarva, and in the mid to upper 70s north and west of the I-95
corridor.

&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
The primary focus during this time period will be on shower
chances with the coastal low Wednesday and perhaps lingering
into the early part of the day Thursday. The low is expected to
be located just offshore the NC/VA coastline Wednesday morning,
and will track slowly northeastward into Thursday. The low is
expected to weaken and become an open trough with time. Even
still, scattered to numerous showers and a few embedded
thunderstorms are expected on Wednesday mainly southeast of the
I-95 corridor, with more isolated coverage elsewhere. How soon
the rain chances diminish will be dependent on how fast the low
degrades, but there is increasing model agreement that Thursday
could end up being dry for most, with just a slight chance for
lingering isolated showers.

Highs on Wednesday will generally be in the upper 60s to lower
70s. With widespread clouds Wednesday night, temperatures won`t
cool much, with most locations remaining in the low-mid 60s.
With at least some breaks in the clouds becoming more prevalent
on Thursday and with significantly less shower coverage,
temperatures are expected to warm into the upper 70s. Slightly
cooler lows are expected Thursday night, ranging from the mid
50s to the lower 60s.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
A dry cold frontal passage is expected on Friday, with high
pressure centered over portions of Ontario and the Northern
Great Lakes shifting southeastward into our area. This will lead
to quiet weather through the weekend and into early next week.

A warm Friday is expected, with temperatures generally in the
mid 80s. Once the cold front clears the area, temperatures
should be noticeably cooler. The Friday night through Sunday
time frame should feature partly to mostly clear skies with
highs in the low-mid 70s and lows in the low-mid 50s. Monday
will likely be slightly warmer, but most locations still
remaining below 80.

The upper-pattern may become more unsettled Monday and beyond,
but for now precipitation chances Monday look to be minimal.

&&

.AVIATION /19Z MONDAY THROUGH SATURDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY and surrounding areas.

Rest of today...VFR. E winds around 10 kt, with occasional
gusts of 15 to 20 kt, especially at KMIV and KACY. High
confidence.

Tonight...Generally VFR. Some light SHRA may impact KMIV/KACY,
but restrictions not expected. Patchy fog is possible, but
confidence is low on fog impacting any given terminal with sub-
VFR conditions. E-NE winds 8 to 12 kt. Low confidence.

Tuesday...VFR at KRDG/KABE. VFR with the low potential for sub-
VFR conditions in light SHRA, mainly in the afternoon, at
KTTN/KPNE/KPHL/KILG. Sub-VFR in SHRA at KMIV/KACY. Cannot rule
out a TSRA at KACY, especially in the afternoon. E-NE winds 10
to 15 kt with gusts up to 20 kt, through around 15 kt with 25 to
30 kt gusts at KMIV/KACY. Low confidence.

Tuesday night...Sub-VFR in SHRA.

Outlook...

Wednesday through Wednesday night...Periods of sub-VFR
conditions are possible in scattered showers and perhaps a few
embedded storms.

Thursday...Primarily VFR. A few isolated showers could linger
across the area, with periods of sub-VFR conditions still not
out of the question.

Thursday night through Saturday...VFR. No significant weather.

&&

.MARINE...
Low pressure will meander over the Mid-Atlantic through at
least Tuesday night. Visibility restrictions in rain and fog
will develop starting late tonight and will continue through at
least Tuesday night. A few thunderstorms are possible as well
during this time.

In terms of wind, east to northeast winds will ramp up tonight.
Small Craft Advisories are either in effect or will go into
effect by late tonight on all waters. Winds will become 15 to 20
kt with 25 to 30 kt gusts and seas building to 3 to 5 feet over
northern ocean waters and to 5 to 7 feet over southern ocean
waters.

Will issue a Gale Warning for southern New Jersey ocean waters,
Delaware ocean waters, and lower Delaware Bay for Tuesday as
winds 35 to 40 kt wind gusts will develop. The Gale Warning may
have to be extended into Tuesday evening, but for now, it looks
like the period of gale force winds will be relatively brief,
and mainly during Tuesday afternoon. Once the Gale Warning ends,
a SCA will be needed for those waters. SCA will be in effect
for all other waters through Tuesday night.

Outlook...

Elevated winds and seas could potentially linger into Wednesday
depending on the rate at which the low decays. As of now, the
anticipation is that winds and seas will have diminished below
25 kt and 5 feet by daybreak Wednesday, but this will continue
to be monitored going forward.

Wednesday afternoon and beyond, no marine headlines are
anticipated with winds remaining below 25 kt and seas below 5
feet.

Rip Currents...

For today, the winds back to easterly at around 10 to 15 mph
and breaking waves increase to around 2 to 3 feet with a
continuing easterly swell around 8 seconds. Due to the winds
becoming onshore along with building wave heights the risk for
dangerous rip currents is expected to increase to a MODERATE
risk for all of the New Jersey Shore and Delaware Beaches.

For Tuesday, northeast winds further increase to around 15 to
25 mph with breaking waves increasing to 3 to 5 feet. This will
result in a HIGH risk for the development of dangerous rip
currents.

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

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...None.
NJ...High Risk for Rip Currents from Tuesday morning through Tuesday
     evening for NJZ014-024>026.
DE...High Risk for Rip Currents from Tuesday morning through Tuesday
     evening for DEZ004.
MD...None.
MARINE...Small Craft Advisory from midnight tonight to 6 AM EDT
     Wednesday for ANZ430.
     Small Craft Advisory until 6 AM EDT Tuesday for ANZ431-453>455.
     Gale Warning from 6 AM to 6 PM EDT Tuesday for ANZ431-453>455.
     Small Craft Advisory from 2 AM Tuesday to 6 AM EDT Wednesday
     for ANZ450.
     Small Craft Advisory from 6 PM this evening to 6 AM EDT
     Wednesday for ANZ451-452.

&&

$$

SYNOPSIS...Cooper
NEAR TERM...MPS
SHORT TERM...Cooper
LONG TERM...Cooper
AVIATION...Cooper/MPS
MARINE...Cooper/MPS