837
FXUS61 KPHI 311452
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
1052 AM EDT Sun Aug 31 2025

.SYNOPSIS...
The dominant feature in our weather pattern through Wednesday
will be a large area of surface high pressure over much of the
northeastern U.S. An area of low pressure is expected to develop
well off the coast and lift northeast through mid week. A cold
front is then expected to arrive into our region Thursday night
into Friday. High pressure then returns for next weekend.

&&

.NEAR TERM /THROUGH TONIGHT/...
No changes to the forecast needed so far today. Broad troughing
remains across the eastern US, with a stronger shortwave axis
extending from portions of New Brunswick and Nova Scotia into
far northern New England. This feature will track northeastward
away from our area through the period. Meanwhile, weaker
troughing will remain in place. At the surface, high pressure
will over the Great Lakes will spread eastward into the Mid-
Atlantic and New England. A surface cyclone over the Atlantic
waters off the Mid- Atlantic coast should track east-
northeastward, remaining well offshore.

For much of the day, skies will be mostly clear. However, cloud
cover will begin to increase by mid-late afternoon. Even with
some increase in cloud cover, it is still expected to warm into
the mid 70s for most locations, with some areas nearing or
reaching 80.

Skies tonight will remain partly to mostly cloudy, with warmer
temperatures. Overnight lows in the low-mid 50s can be expected
for most locations, with upper 50s to lower 60s in coastal
locations and for the urban corridor.

&&

.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
By Monday and Tuesday, the surface high will be shifting closer
to the area. In the upper levels, a cutoff low from the
departing trough will meander towards northern New England by
Tuesday. Many of the latest deterministic model runs now show
the coastal low staying well east of the coast and starting to
progress northeastward during this time - likely not resulting
in any impacts to our weather.

The net result is continued tranquil and dry conditions. High
temps on Monday and Tuesday will mainly be in the 70s to around
80 degrees with low temps at night mainly in the 50s (with 40s
in sheltered locations and 60s along immediate coastal areas).

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
Focus in the long term remains on the cold front expected to
cross through the region Thursday night into Friday.

For Wednesday and Thursday, the main change from the previous
forecast is that with the coastal low now expected to be well
east of our region, there will be a longer window of opportunity
for deep southwest flow to develop. This could spark a brief
warming trend. Current blend of guidance has highs both days
ranging from the mid 70s to lower 80s, but if this trend
continues, there is a potential for the forecast to trend
warmer, especially if the timing of the cold front continues to
be Thursday night.

Best chance for widespread rain will be just ahead of and with
the cold frontal passage. Thus, have a 20 to 40% chance of rain
Thursday afternoon, but then the chance increases to 40 to 70%
Thursday night. Depending on the forward progression of the
front, some showers may linger into Friday as well. However,
once the front clears the region, precipitation chances should
dwindle with the return of cooler and dry weather returning by
the start of next weekend.

&&

.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY and surrounding areas.

Today...VFR. SCT/BKN high clouds increase from southwest to
northeast 22-00Z. Northeasterly wind 5-10 kt. A sea breeze may
develop and make it as far inland as MIV and ACY during the 19-
21Z time frame, causing wind to be east to east- southeasterly.
High confidence overall.

Tonight...VFR. SCT/BKN mid- and high clouds. Northeasterly wind
5-10 kt quickly diminishing to light and variable. High
confidence.

Outlook...

Monday through Wednesday night...VFR. No significant weather
expected.

Thursday...Sub-VFR conditions possible with a chance of
showers, especially Thursday night.

&&

.MARINE...
Through tonight...No marine headlines. Winds and seas will
begin to increase tonight. However, it currently appears that
conditions will remain below SCA criteria, with east-
northeasterly wind increasing to around 15 kt and seas to 3-4
feet.

Outlook...

Monday and Tuesday...Winds and seas should generally remain
below SCA criteria. However, seas could get close to 5 feet,
especially further off shore, and wind gusts may exceed 20 kt at
times.

Wednesday and Thursday...Winds and seas should stay below SCA
criteria.

Rip Currents...

For today, northerly wind 5-10 mph will become easterly during
the afternoon. Breaking wave heights 1-2 feet. Easterly swell
around 2 feet at 4 to 6 seconds in length. Will maintain the LOW
risk for the development of dangerous rip currents for all
beaches.

For Monday, northeasterly wind 10-15 mph. Breaking wave heights
2-3 feet. Easterly swell around 3 feet at 6-7 seconds in
length. Given the modestly increased winds, wave heights, and
swell, will upgrade to a MODERATE 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...DeSilva/Johnson
NEAR TERM...Cooper/Robertson
SHORT TERM...DeSilva/Johnson
LONG TERM...DeSilva/Johnson
AVIATION...Cooper/Johnson/Robertson
MARINE...Cooper/Johnson