565
FXUS61 KPHI 312013
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
413 PM EDT Sun Aug 31 2025

.SYNOPSIS...
High pressure will remain across the region through Wednesday,
providing continued dry conditions and below normal
temperatures. A pair of cold fronts will impact the region
Thursday night through Friday night, resulting in chances for
showers and increasing humidity. High pressure will return again
into next weekend.

&&

.NEAR TERM /THROUGH MONDAY NIGHT/...
Fair conditions will continue tonight through Monday night as
high pressure builds out of the Great Lakes region and into New
England tonight. The high will continue toward the Canadian
Maritimes Monday into Monday night. Although the high will be to
our north, it will nose its way into the Mid Atlantic region,
keeping a northeast to east wind direction. This will allow for
temperatures to remain near normal through Monday night. There
will be scattered to broken clouds, especially as daytime fair
weather cumulus clouds develop, but no precipitation is expected
at this time.

&&

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
The Tuesday through Wednesday night period will feature much of
the same dry and pleasant weather conditions we`ve been
experiencing this weekend.

A broad, closed upper trough will begin to deamplify and lift
northeast away from our region a stronger closed upper low
begins approaching the Great Lakes by Wednesday. At the surface,
high pressure will remain in place on Tuesday, then begin
shifting offshore into Wednesday as a cold front begin to
approach from the northwest. Northeast to east winds Tuesday
will settle out of the south on Wednesday.

Temperatures will remain below normal through this period,
along with low dewpoints (low humidity) in the 50s. Dewpoints
should begin to rebound some by late Wednesday and into
Wednesday night with the change to a southerly surface flow.
This could introduce a chance for low clouds and/or fog
development Wednesday night. Otherwise, high temperatures will
remain mostly a few degrees below normal in the mid 70s to near
80 degrees. Low temperatures largely in the 50s, trending a
couple degrees warmer on Wednesday night compared to Tuesday
night.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
A pattern change to unsettled conditions is expected for the
end of the week beginning Thursday through Friday night.
Widespread rainfall is anticipated late Thursday through Friday
as a pair of cold fronts impacts the region,

A closed upper low will remain stalled out between the upper
Great Lakes and Hudson Bay region in Ontario Thursday through
late Friday before weakening and lifting north into the weekend.
At the surface, an initial cold front will approach the area
Thursday night, but this will largely weaken and dissipate
(frontolysis) in our area by early Friday. Another front will
approach late Friday, crossing the area and eventually moving
offshore by Saturday. Canadian high pressure will then gradually
build into the region over the weekend.

The system impacting the region Thursday through Friday has
generally slowed in forecast progression. This should result in
Thursday being mostly dry for our area, at least through the
early afternoon hours. A band of showers or perhaps stratiform
rain with embedded pockets of heavier rain will push into the
area ahead of the cold front from the northwest by Thursday
evening and into the overnight period. PoPs are highest during
the Thursday night period, and largely range from around 50%
toward the south to 70% toward the north. There should be a lull
in showers sometime early Friday, then another round with the
second front that will move into the area by later in the day or
overnight. PoPs Friday range between 30% to the south and
around 50-60% to the north.

PWats will increase to around the 1.5" to 1.8" range, which
should help give much of our area some much needed rainfall. We
do not have an official rainfall forecast yet, but as of this
writing, we should experience a widespread 0.25" (south) to 1"
(north) of rainfall per WPC guidance. There could be locally
higher amounts, but long story short, this should be a largely
beneficial rainfall event with no flood hazards considering how
dry it has been the past couple weeks. A few thunderstorms are
possible as well, but not of the severe variety.

Temperatures in the Thursday through Friday night period will
be closer to normal compared to recent days, with highs in the
upper 70s to mid 80s. Dewpoints will also increase a good bit
into the 60s, so humidity will be noticeably higher, but not
oppressively so.

High pressure will gradually build toward the region over the
weekend, with temperatures returning to mostly below normal
values. High temperatures in the 70s to near 80 degrees, and low
temperatures ranging from near 50-60 degrees.

&&

.AVIATION /20Z SUNDAY THROUGH FRIDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY and surrounding areas.

Rest of today...VFR conditions prevail. Northeast to east winds
5-10 knots, with occasional gusts around 15-20 knots. High
confidence.

Tonight...VFR conditions continue. Winds likely shift to east
to southeast this evening, then light and variable most places
overnight. Any direction will shift back to the northeast. High
confidence.

Monday...VFR conditions expected. Northeast to east winds 5-10
knots increase to 10-15 knots with gusts 15-20 knots through the
day. High confidence.

Outlook...

Monday night...VFR conditions. Easterly winds around 5-10 knots
become light and variable overnight. High confidence.

Tuesday through Wednesday...VFR. No significant weather.

Wednesday night...Potential for restrictions due to low clouds
and fog.

Thursday through Friday...VFR conditions should prevail
initially, but low clouds, showers, and potential for thunder
will develop late Thursday through Friday.

&&

.MARINE...
Conditions are expected to remain below advisory levels.
However, winds will gust in the low 20s on Monday, and seas will
approach 4+ feet.

Outlook...

Tuesday...Seas will be near 5 feet. Otherwise, no marine
hazards expected with fair weather.

Tuesday night through Friday...No marine hazards expected. Fair
weather through Wednesday. Potential for fog Wednesday night.
Chances for showers and storms Thursday night through Friday.

Rip Currents...

Monday...Northeast winds around 15-20 MPH and 2 to 3 foot
breaking waves will result in a MODERATE risk for the
development of rip currents.

Tuesday...Winds go more mortherly and shore parallel while also
decreasing to around 10 MPH or so. Breaking waves remain around
2 to 3 feet, with a 6 to 8 second period. Given the lower winds
and slight shift in wind direction, a LOW risk for the
development of rip currents.

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

&&

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

&&

$$

SYNOPSIS...Staarmann
NEAR TERM...Robertson
SHORT TERM...Staarmann
LONG TERM...Staarmann
AVIATION...Robertson/Staarmann
MARINE...Hoeflich/Robertson/Staarmann