591
FXUS61 KPHI 272246
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
646 PM EDT Wed Aug 27 2025

.SYNOPSIS...
High pressure centered over the midwest this afternoon will slide
eastward across the Mid-Atlantic this evening into the overnight
before shifting offshore Thursday. A cold front then crosses our
area later Thursday night into Friday followed by high pressure over
the weekend. An area of low pressure may develop off the southeast
coast and move north around the early to middle part of next
week.

&&

.NEAR TERM /THROUGH THURSDAY/...
High pressure remains our dominant weather feature through
tomorrow. Overnight, we stay dry and mostly clear. Lows tonight
fall into the upper 40s to upper 50s.

For tomorrow, there is still a longwave trough in the upper-levels
across the northeast with a piece of shortwave energy moving through
Thursday. Although high pressure will be in control at the surface,
that piece of shortwave energy could be enough for some light
spotty showers during the day Thursday with some clouds also
passing through. Overall, not expecting much in the form of rain
through Thursday evening. Highs on Thursday are in the 70s.

&&

.SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...
An upper-level trough is forecast to amplify into the Northeast and
Mid-Atlantic regions Thursday night into Friday. This will occur as
a cold front approaches the area by later Thursday night and then
crosses the region through Friday. A few showers may start to arrive
by later at night across the western areas as some moisture return
continues ahead of the cold front. Overall though, the moisture
return does not look all that robust and the main forcing sliding by
to our north should limit the amount of showers starting to arrive
from the west. Temperatures are forecast to be on the cooler side
(below average).

For Friday, a strong upper-level trough continues to swing across
the Northeast and Mid-Atlantic regions. The guidance is in good
agreement regarding the presence of this trough, with most of the
guidance showing a closed low evolving north of Lake Ontario. This
trough will continue to drive a cold front across our area. The
timing may be fast enough to not occur during peak heating and thus
limiting the coverage of showers/thunder. In addition, the moisture
return is not all that robust and with the stronger forcing sliding
by to our north, the chances for any showers/thunder is on the low
side (20-30 percent POPs mainly just for our eastern / NE zones).
Temperatures will be mostly below average, and dew points increase
ahead of the front well into the 50s before falling again by late
day behind the front.

The aformentioned upper level low will likely linger to our
north through Saturday but our weather pattern will be dominated
by surface high pressure bringing dry and cool weather under
mainly clear to partly cloudy skies for Friday night and
Saturday.

&&

.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
An upper level trough will gradually depart to our east and
northeast through the rest of the weekend into early next week as it
moves through Atlantic Canada. Meanwhile, broad surface high
pressure will continue to dominate our weather Saturday night
through at least Monday. Temperatures during this period look to be
near to a bit below average with Monday being the warmer of the two
days compared to Sunday. Generally expect highs in the 70s to around
80.

Beyond next Monday, there`s a lot of uncertainty in the forecast as
the 0Z ECMWF and some of the GEFS ensembles continue to indicate a
coastal storm developing near the SE coast and then moving north. If
this were to occur the area would turn rainy and gusty for a time
around about next Tuesday and/or Wednesday. However the operational
GFS and the GEM keep the area dry dominated by high pressure. Given
the uncertainty we continue to stay with the NBM which keeps the
area mainly dry Tuesday through Wednesday with POPs around 10 to 15
percent. Temperatures should continue to be right around if not a
bit below average.

&&

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

Tonight...VFR with WNW wind tapering to 5 kts or less. Winds
look to become light and variable for a period overnight. High
confidence.

Thursday...VFR with a SW wind around 5-10 knots. A sea-breeze at
KACY and KMIV could result in more southerly winds, and a few
gusts near 20 kt, especially at KACY. High confidence.

Outlook...

Thursday night through Friday...VFR. A few showers or a thunderstorm
possible, otherwise mainly VFR.

Saturday through Monday...VFR expected.

&&

.MARINE...
Conditions are expected to be below Small Craft Advisory levels
through tonight as seas will be around 2 to 3 feet and WNW
winds will be around 10 knots with gusts around 20 knots. Winds
decrease to 5-10 knots overnight out of the west.

On Thursday, seas remain 2-3 feet but the wind will pick up out
of the southwest by the afternoon and continue into Thursday
night. Winds will be 10-15 knots with gusts around 20 knots.

Outlook...

Thursday night through Monday...For Thursday night, southwest winds
may just reach Small Craft Advisory criteria for a time,
especially over our northern ocean zones. But otherwise the
conditions through this period are expected to be below Small
Craft Advisory levels.


Rip Currents...

For Thursday, winds shift southerly but remain around 10 mph
through much of the day. Breaking wave heights will remain
around 1-2 feet with a few 3 foot waves possible north. Easterly
swell will remain around 1-2 feet around 7-9 seconds in length.
Guidance still suggests marginally higher seas and swell for
coastal Atlantic and north, so again went with a MODERATE RISK
for this region with a LOW RISK for coastal Cape May NJ and
Sussex DE.

For Friday, winds remain offshore out of the SW to WSW around
10-15 mph. Breaking wave heights remain around 1 to 2 feet.
Combined with a weak easterly swell around 1-2 feet every 7 to
8 seconds, this will allow for a LOW RISK for rip currents
across 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/Gorse
NEAR TERM...Guzzo/Hoeflich
SHORT TERM...Fitzsimmons/Gorse
LONG TERM...Fitzsimmons
AVIATION...Fitzsimmons/Guzzo/Hoeflich
MARINE...Fitzsimmons/Guzzo