459
FXUS61 KPHI 301019
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
619 AM EDT Sat Aug 30 2025

.SYNOPSIS...
The dominant feature in our weather pattern through Wednesday
will be a large area at the surface of high pressure over much of
the northeastern U.S. An area of low pressure is expected to
develop off the coast and lift northeast from Wednesday through
Friday. A cold front is forecast to arrive into our region
Thursday into Friday.

&&

.NEAR TERM /THROUGH TONIGHT/...
A closed upper-low initially centered over southern portions of
Quebec will shift gradually eastward through the period into
portions of New Brunswick and Nova Scotia. This will keep
enhanced northwesterly mid- and upper-level flow across the area
into this afternoon. As the low shifts eastward, heights will
rise across the area and upper-flow will weaken. At the surface,
a cold front will continue to shift farther off of the
Northeast coastline as high pressure from the northwest expands
southeastward into our area.

It is a relatively chilly morning by late August standards
(temperatures generally in the upper 40s across eastern PA and
northern NJ, and low-mid 50s elsewhere). By this afternoon,
partly to mostly sunny skies are expected. Highs today are
expected to be in the mid 70s for most locations, though they
may remain in the upper 60s across the Poconos. All-in-all, a
very pleasant day looks to be in store.

Tonight, with light northwesterly winds and mostly clear skies,
effective radiational cooling is expected. Low temperatures
will be similar to this morning- in the mid-upper 40s across
most of eastern PA and northern NJ and low-mid 50s across
southeastern PA, southern NJ, and the Delmarva.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
The upper level trough begins to slide further northeast away
from our region (though it looks like the base of the trough
will cutoff, but is expected to weaken quickly). As it does so,
the surface high will build in towards our region.

Depending on how quickly the surface high builds in and where
the upper level cutoff low sets up, it looks like our region
will have a deep layer of easterly or northeasterly flow,
keeping our area with continued below average temperatures.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
The main period to watch in the long term is Thursday into
Friday which is the next chance for widespread rain to the area.

Tuesday and Wednesday will be a continuation of the weather
pattern this weekend - generally tranquil with temperatures
slightly below average. There may be a slight warming trend on
Wednesday as a weak mid level short wave ridge tries to build
over the region, but at this point, there is a 60 to 80% chance
temperatures will stay below normal.

Guidance continues to depict a coastal low developing off the
southeastern U.S. coast Wednesday into Thursday and then
progressing northeastward. There was generally a slight
westward shift with much of the 00Z guidance, though almost all
guidance depicts the low off the coast, and rather weak. There
is a 20 to 30% chance that rain on the west side of the low will
make it to coastal areas, but it doesn`t appear to have any
signs of being impactful.

The main focus though is on a cold front that approaches the
region Thursday into Friday. There is a 40 to 50 % chance of
rain across the area as this front will cross through the
region. Another modest cool down is expected behind the front.

&&

.AVIATION /10Z SATURDAY THROUGH WEDNESDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY and surrounding areas.

Today...VFR. Northwest wind 5-10 kt. A sea breeze may develop
and make it as far inland as ACY, turning winds more southerly.
High confidence overall.

Tonight...VFR. Northwest wind around 5 kt becoming light and
variable. High confidence.

Outlook...

Sunday through Wednesday...Prevailing VFR. No significant
weather.

&&

.MARINE...
Through tonight...No marine headlines. Winds generally
northwest at 10-15 kt, with a brief period of southerly wind
possible this afternoon. Seas 2 to 3 feet.

Outlook...

Sunday through Wednesday...Winds and seas are expected to remain
below Small Craft Advisory conditions.

Rip Currents...

For today, northwesterly wind 5-10 mph in the morning will
become southerly during the afternoon. Breaking wave heights 1-2
feet. Easterly swell around 2 feet at 6-8 seconds in length.
Given these factors, have maintained a LOW risk for the
development of dangerous rip currents at all beaches.

For Sunday, northerly wind 5-10 mph will become easterly during
the afternoon. Breaking wave heights 1-2 feet. Easterly swell
around 2 feet at 4-5 seconds in length. There is some indication
that breaking wave heights and swells could increase in size
some with onshore flow during the afternoon. However, given the
anticipated short period and lack of stronger winds, will
maintain the LOW risk for the development of dangerous rip
currents for all beaches.

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

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...None.
NJ...None.
DE...None.
MD...None.
MARINE...None.

&&

$$

SYNOPSIS...Fitzsimmons/Johnson
NEAR TERM...Cooper
SHORT TERM...Johnson
LONG TERM...Johnson
AVIATION...Cooper/Johnson
MARINE...Cooper/Johnson