762
FXUS61 KPHI 290814
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
414 AM EDT Mon Sep 29 2025

.SYNOPSIS...
High pressure is in control through Tuesday. A weak cold front moves
through on Tuesday night before an expansive area of high pressure
moves in for the end of the week and the upcoming weekend.

&&

.NEAR TERM /THROUGH TONIGHT/...
Broad high pressure lies over central Canada and will build to the
south and east. High pressure centered over western New York and
western Pennsylvania will slide offshore tonight, and then high
pressure over central Canada will build down into western New York
and western Pennsylvania. Meanwhile, distant Hurricane Humberto will
lift to the north and will be some 500 miles southeast of Cape
Hatteras and Tropical Storm Imelda will lift towards the Southeast
U.S. coast tonight.

In terms of sensible weather, abundant low level moisture will
result in areas of fog, mainly across southeast New Jersey,
Delaware, the eastern shores of Maryland, and into the Delaware
Valley. That fog will lift and dissipate shortly after sunrise. High
clouds will increase and thicken throughout the day as shortwave
energy associated with a closed upper low over the Southeast U.S
lifts towards the Northeast. Another seasonably warm day on tap
with highs in the upper 70s to around 80.

Patchy fog may develop once again tonight, but increasing high
clouds may prevent that from developing. Lows tonight will be in the
upper 50s to low 60s.

&&

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
High pressure retreats to the south on Tuesday ahead of an
approaching cold front. An upper level trough over the Mid-Atlantic
sags south as well. The trough will be close enough to keep things
mostly cloudy on Tuesday, but far enough away for any precipitation
to get into our area. Even with mostly cloudy skies,
temperatures should still be quite mild with highs in the mid to
upper 70s and even low 80s.

Cold front comes through on Tuesday Night, ushering in a fall-like
airmass. The front will not have moisture to work with, so it
will be a dry frontal passage. We begin to feel the effects of
the Canadian airmass on Tuesday Night as lows dip into the mid
to upper 40s north and west of the I-95 corridor. With the front
not getting through the southern half of the area until late,
lows stay in the 50s or even low 60s.

High pressure begins to nudge in from the north on Wednesday, with a
cool airmass overhead. There will be a notable northeast breeze as a
tight pressure gradient sets up with the incoming high and two
tropical systems exiting stage right in the Atlantic. Winds near the
coast could gust up to 40 MPH at times, with lesser gusts the
further inland you go. While skies are mostly sunny,
temperatures only get into the upper 60s/low 70s.

Quiet on Wednesday night with mostly clear skies and temperatures
dropping into the 40s, though some warmer spots such as the urban
corridor and Delmarva hover around 50. Some elevated areas in the
Poconos and northern NJ could drop into the 30s, though no frost
concerns expected just yet. A steady northeast wind will keep the
bottom from falling out completely with temperatures overnight,
though there will be a fall chill in the air.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
Large-scale upper level ridging moves in on Thursday, and will
remain overhead through the weekend, resulting in dry
conditions. At the surface, high pressure slowly inches in from
the north on Thursday, then settles overhead on Friday and
remains parked overhead through the weekend. It will be a bit
breezy, especially along the coast, on Thursday as departing
Humberto and Imelda and the incoming high keep a tight pressure
gradient in place. That gradient weakens with the high getting
overhead by Friday.

Overall, it should be a nice stretch of early October weather.
Temperatures will be a few degrees below normal to start the long-
term on Thursday-only in the 60s, but should moderate each day,
eventually getting into above normal territory by the end of the
weekend (upper 70s).

&&

.AVIATION /08Z MONDAY THROUGH FRIDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY and surrounding areas...

Early morning hours...VFR initially. VSBY restrictions
developing at all but KPNE/KPHL with at least MVFR conditions.
IFR/LIFR conditions developing at KMIV. Nearly calm winds. Low
confidence on flight category conditions.

Today...Any sub-VFR conditions lift to VFR by 13Z. E-NE winds 5
to 10 kt. High confidence.

Tonight...Generally VFR. Low probability (20 to 30 percent) for
sub-VFR conditions in fog. Light NE winds. Low confidence.

Outlook...

Tuesday through Tuesday Night...VFR. No significant weather. Wind
gusts near 20 kt expected at KACY.

Wednesday through Wednesday...VFR. Wind gusts 15-20 kt anticipated
at all terminals with gusts nearing 30 kt near KACY.

Thursday through Friday...VFR. Wind gusts 20-25 kt expected at KACY
on Thursday.

&&

.MARINE...
Sub-Small Craft Advisory conditions today. East to northeast winds
10 to 15 kt with seas 3 to 4 feet. SCA conditions develop tonight.
Winds turn northeast at 10 to 15 kt. Seas will begin to build to 3
to 5 feet as Hurricane Humberto lifts to the north and will be some
500 miles southeast of Cape Hatteras, and Tropical Storm Imelda
lifts along the Southeast Coast. SCA goes into effect for the ocean
waters starting tonight.

Outlook...

Tuesday...A Small Craft Advisory is in place for all ocean zones as
seas 5 to 8 feet are expected. Sub-SCA conditions on Delaware Bay.

Tuesday Night through Wednesday...A Gale Watch was posted for ocean
zones south of Manasquan Inlet as 30-40 kt wind gusts are expected.
North of Manasquan Inlet, an SCA remains in effect through Thursday
as winds should stay right around 30 kt. A Small Craft Advisory was
issued for Tuesday Night through Wednesday for all of Delaware Bay
as wind gusts of 25-30 kt are anticipated. Seas of 7 to 11 feet are
expected on the ocean.

Wednesday Night through Thursday...Any ocean zones with Gales up
will need a Small Craft Advisory once any Gale headlines expire as
seas remain elevated around 6 to 10 feet. A Small Craft Advisory is
in effect for the lower Delaware Bay and ocean zones north of
Manasquan Inlet through Thursday.

Rip Currents...

For today, the increasing influence of longer period swells
around 13 to 16 seconds combined with there being multiple swell
groups along with northeast winds around 10 to 15 mph will
result in a MODERATE risk for the development of dangerous rip
currents at all beaches. Generally expect wave heights in the
surf zone to be around 2-3 feet.

For Tuesday, the long period swells associated with the tropical
systems to our south will continue to build and this will result in
a HIGH risk for the threat of dangerous rip currents at all beaches.
Generally expect rough surf conditions as wave heights in the surf
zone look to be around 3 to 6 feet. Increasing onshore winds of
10-20+ MPH are expected. Issued a Rip Current Statement for
Tuesday.

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

The SRF product and rip current discussion will end on September
30th.

&&

.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 11 PM Tuesday to 6 PM EDT Wednesday
     for ANZ430.
     Small Craft Advisory from 6 PM Tuesday to 6 PM EDT Thursday
     for ANZ431.
     Small Craft Advisory from 8 PM this evening to 6 PM EDT
     Thursday for ANZ450.
     Small Craft Advisory from 8 PM this evening to 6 PM EDT
     Tuesday for ANZ451>455.
     Gale Watch from Tuesday evening through Wednesday afternoon
     for ANZ451>455.

&&

$$

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