445
FXUS61 KPHI 230016
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
816 PM EDT Fri Aug 22 2025

.SYNOPSIS...
Hurricane Erin is expected to become a post-tropical cyclone as
it heads well out to sea the next few days. Meanwhile, high
pressure centered over the Middle-Atlantic will push east this
weekend. This will allow a cold front to pass through the region
Sunday night into Monday morning, followed by another weak cold
front Tuesday or Wednesday. High pressure will return to finish
out the week.

&&

.NEAR TERM /THROUGH SATURDAY/...
Hurricane Erin is some 400-500 miles southeast of Nantucket
Island and will become post-tropical as it tracks out to sea.
Meanwhile, high pressure centered over western New York and
western Pennsylvania builds overhead this evening before moving
offshore Saturday morning. High pressure will be southeast of
the Gulf of Maine by the end of the day Saturday.

In terms of sensible weather, clear as a bell tonight with
winds becoming nearly calm after midnight tonight. Lows will
vary from the low 60s in and around Philadelphia, and in the mid
and upper 60s along the coasts due proximity to the relatively
warmer ocean waters. Lows away from the urban centers and away
from the coasts will be in the mid to upper 50s, though
radiational cooling conditions may result in locally cooler
temperatures.

Abundant sunshine on Saturday. Return flow setting up behind
the departing high will allow a slightly more humid airmass to
spread into the region with surface dew points rising into the
upper 50s to low 60s. Mild with highs in the low to mid 80s.

&&

.SHORT TERM /SATURDAY NIGHT THROUGH MONDAY/...
High pressure will be offshore on Saturday night setting up a
return flow across the Mid-Atlantic. A cold front will approach
from the west starting Saturday night. A more humid airmass will
slide in overnight, with dew points rising back into the mid
60s. An isolated shower or even a thunderstorm cannot be ruled
out early Sunday morning across the Poconos and Lehigh Valley as
the front continues to approach the forecast area.

With the cold front continuing to track eastward on Sunday,
southerly flow will continue to draw southern humid air
northward into the region, allowing dew points to rise into the
upper 60s. Showers and scattered thunderstorms are expected to
develop Sunday afternoon ahead of the said cold front, and
they`ll continue into Monday. It`s a slow-moving front. Highs
will be in the low to mid 80s both Sunday and Monday. Lows will
be in the upper 50s well north and mid to upper 60s elsewhere.

&&

.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
If you like September weather, this period is for you. In
short, drier air will push in behind the departing cold front
and stick with us through much of the work week. Monday night`s
lows will fall into the mid 50s to low 60s. A weak secondary
front is expected to pass through the region Tuesday or
Wednesday. But only a few light showers will be possible in the
Poconos. So for most, the cool and dry conditions will persist
for the rest of the week. Expect high temperatures to max out in
the 70s (60s Poconos). Overnight lows will mainly be in the
50s. They`ll even drop into 40s across the Poconos, but likely
remain in the lower 60s right along the warmer bays and ocean.

On an aside, the region is slowly starting to see pockets of
abnormally dry conditions once again. The US Drought Monitor
should be something to keep an eye on in the weeks ahead.

&&

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

Tonight...VFR/SKC. South winds 5 kt or less. High confidence.

Saturday...VFR. South winds increasing to near 10-15 kts by
18Z. High confidence.

Outlook...

Saturday night...VFR.

Sunday through Monday...Mainly VFR. Brief sub-VFR conditions
are possible in scattered SHRA/TSRA from Sunday afternoon
through Monday afternoon.

Monday night through Wednesday...VFR expected.

&&

.MARINE...
North to northeast winds 10 to 15 kt will turn east this
evening, then south tonight through Saturday. However, seas will
remain elevated at 8 to 10 feet, subsiding to 5 to 7 feet
tonight, then 3 to 5 feet on Saturday. Small Craft Advisories
remain in effect for the ocean waters through Saturday.

For Delaware Bay, winds and seas will be below SCA criteria.

Outlook...

Saturday night...Low-end residual SCA conditions likely
remaining with us from Ocean County south. Monmouth waters look
sub-SCA. This is still due to elevated seas from the departing
TC Erin.

Sunday through Monday...Sub-SCA conditions. Visibility
restrictions and locally higher winds and seas will be possible
in showers and thunderstorms late Sunday through Monday.

Monday night through Wednesday...Sub-SCA conditions expected.

Rip Currents...

YOU ARE RISKING YOUR LIFE IF YOU GO IN THE WATER!

For Saturday and Sunday, conditions continue to improve but
still expecting high waves of 3 to 5 feet and a long period 11
second swell with Hurricane Erin pulling away. A HIGH risk for
development of life-threatening rip currents will remain through
the end of the weekend.

The High Surf Advisory has been allowed to expire as scheduled
as of 8 PM Friday. While rough surf conditions are still
expected for much of the weekend, the breaking wave heights will
continue to diminish gradually through the weekend and remain
near 3 to 5 feet.

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

&&

.TIDES/COASTAL FLOODING...
Coastal flooding concerns persist despite Hurricane Erin
pushing further out to sea. While northeast winds have been
weaker today, the persistent northeast flow and strong swells
from Erin will continue the threat for tidal flooding and push
of water onshore, especially during the upcoming late
evening/overnight high tide. Widesperad Minor to Moderate
coastal flooding is expected across all coastlines, including
along the Delaware Bay and tidal Delaware River. Coastal Flood
Warnings remain in effect from Manasquan Inlet, NJ through
Fenwick Island, DE, including the Delaware Bay. Coastal Flood
Advisories are now in effect from Perth Amboy, NJ to Manasquan
Inlet, NJ and along the tidal Delaware River. Coastal Flood
Advisories are now up for the Eastern Shores of Maryland thanks
to southeast flow beginning tonight.

Heading into Saturday, the impacts of Erin will continue to
lessen, particularly on the oceanfront, as the onshore swells
begin to weaken. However, due to persistent onshore/shore
parallel flow, water will have difficulty draining out of
backbays in both NJ and DE, as well as the Delaware Bay and
tidal Delaware River. As a result, continued widespread minor
tidal flooding is expected with localized moderate tidal
flooding possible, particularly on the backbays with the
Saturday night high tide. As a result, the Coastal Flood
Warnings as well as the Coastal Flood Advisories for the tidal
Delaware River have been extended through the high tide cycle
Saturday night into early Sunday.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...Coastal Flood Advisory until 6 AM EDT Sunday for PAZ070-071-
     106.
NJ...Coastal Flood Advisory until 2 AM EDT Sunday for NJZ016.
     Coastal Flood Warning until 2 AM EDT Sunday for NJZ020>027.
     High Risk for Rip Currents through Sunday evening for NJZ014-
     024>026.
     Coastal Flood Advisory until 1 AM EDT Saturday for NJZ012>014.
     Coastal Flood Advisory until 6 AM EDT Sunday for NJZ017>019.
DE...Coastal Flood Advisory until 2 AM EDT Sunday for DEZ001.
     Coastal Flood Warning until 2 AM EDT Sunday for DEZ002>004.
     High Risk for Rip Currents through Sunday evening for DEZ004.
MD...Coastal Flood Advisory from 7 AM to 11 AM EDT Saturday for
     MDZ012.
     Coastal Flood Advisory until 9 AM EDT Saturday for MDZ015-019-
     020.
MARINE...Small Craft Advisory until 11 AM EDT Saturday for ANZ450.
     Small Craft Advisory until 6 AM EDT Sunday for ANZ451>455.

&&

$$

SYNOPSIS...Kruzdlo/MPS/OHara
NEAR TERM...MPS
SHORT TERM...Kruzdlo
LONG TERM...Kruzdlo
AVIATION...Kruzdlo/MPS/Staarmann
MARINE...AKL/Kruzdlo/MPS/Staarmann
TIDES/COASTAL FLOODING...AKL/Kruzdlo