040
FXUS61 KPHI 052242
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
642 PM EDT Tue Aug 5 2025

.SYNOPSIS...
High pressure will remain to our north and northeast through
the end of the week, providing a prolonged stretch of dry
weather and relatively mild temperatures. This high will shift
farther offshore over the weekend and early next week.

&&

.NEAR TERM /THROUGH WEDNESDAY/...
Heading into tonight, any remaining showers to the south should
dwindle as mostly cloudy and hazy skies continue. Winds will
remain light out of the east with lows tonight mainly in the 60s
with low 70s in the immediate urban areas and along the coast.

High pressure will continue to gradually build in from the
north and east on Wednesday which will keep onshore flow
continuing across the area. This will keep temperatures below
average with highs mainly in the low to mid 80s with dew points
in the 60s. Cloud cover shall persist across much of the area as
some energy aloft passes by, with some clearing out towards
western areas late in the day -- and possibly some more
hazy/smokey skies. Perhaps a few weak, spotty showers will make
their way into the Delmarva for the afternoon, but most locales
should remain dry.

&&

.SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY NIGHT/...
The influence of high pressure building to our north and then
northeast will continue to result in an onshore flow regime.
This may strengthen some as the pressure gradient tights a bit
with weak low pressure well to our south. This will result in
temperatures during the day Thursday mostly below average and
also dew points mostly in the low to mid 60s, although the dew
points may mix down a little each afternoon.

Some weak convergence may occur as a result with perhaps a
brief shower Wednesday evening, mainly across parts of our
southern zones. The probabilities of this though are rather low
at this time. Some drier air may arrive then on Thursday with
more sunshine currently forecast.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
Summary...Becoming more humid with some increase chances for
some convection.

Synoptic Overview...A rather weak upper-level trough slides
across the Northeast Friday into Saturday beneath a ridge that
slides into the Canadian Maritimes. An upper-level ridge to our
west then builds east and across our area during the weekend and
early next week. High pressure centered to our northeast Friday
into Saturday shifts east, however remains extended
southwestward across our area. The surface high shifts farther
east Sunday and Monday. In addition, an area of low pressure off
the Southeast U.S. coast may end up meandering near that area
into early next week.

For Friday and Saturday...Despite a very weak upper-level
trough glancing the Northeast, a ridge to its north will drive
surface high pressure centered to our northeast. This will
extend down across our area. A coastal front/trough near the
Southeast U.S. coast looks to support a surface low and that
will tighten the pressure gradient some northward. An onshore
flow will continue and this will keep temperatures near average.
It appears that the presence of this surface high will keep dew
points in check as well, although some increase is forecast
mainly across our southern areas on Saturday. Overall though,
not all that humid across our area for early August.

For Sunday through Tuesday...An upper-level ridge is forecast
to build across our area and this will push surface high
pressure more to our east with time. As this occurs, our low-
level flow will veer more out of the south especially on Monday.
As the surface high gradually weakens on its western flank, the
weak surface low well to our south may drift northward some
with a surface trough also starting to extend into our area. The
more southerly flow will advect more moisture across the area
and therefore it will become increasingly more humid. Daytime
temperatures closing in on 90 degrees for many parts of our
area, especially on Monday, combined with more humid conditions
will introduce the chance for some convection (currently only
20-30 percent). There remains uncertainty on how much forcing
for ascent will be present to support convective development,
especially associated with a northward extension of a surface
trough. Any convection may just be air mass driven. Temperatures
could be well into the low to mid 90s again by Tuesday.

&&

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

Tonight...VFR with BKN high clouds. Southeast winds becoming
northeast overnight around 5 kt or less, variable at times.
Based on some of the observations and model guidance, added HZ
to the TAF at KRDG and KTTN. This will bring VSBY to 6SM at
times, but cannot rule out brief MVFR VSBYs due to HZ. Some
guidance also wants to bring lower CIGs and VSBYs to KABE/KRDG,
but confidence was not high enough to include in the TAF at this
time. Winds generally out of the east/southeast 5 kt or less.
Moderate confidence.

Wednesday...VFR with SCT/BKN high clouds. East winds around 10
kt. Visibility restrictions possible to due to smoke/haze
aloft, but confidence remains low at this occurrence. High
confidence otherwise.

Outlook...

Wednesday night and Thursday...Some local fog/low clouds
possible Wednesday night into Thursday morning, otherwise VFR.

Friday through Sunday...VFR overall.

&&

.MARINE...
No marine headlines are in effect through Wednesday. Easterly
winds generally around 10-15 kt may occasionally gust up to 20
kt on Wednesday. Seas of 3-4 feet. Spotty showers possible
across southern ocean waters, but otherwise, fair weather is
expected.

Outlook...

Wednesday night through Friday...Small Craft Advisory
conditions possible across our ocean zones, due to 5 foot seas
with wind gusts to near 25 knots at times. The conditions may
drop below Small Craft Advisory on Friday.

Saturday through Sunday...The conditions are anticipated to be
below Small Craft Advisory criteria.

Rip Currents...

For Wednesday and Thursday, easterly winds will increase to 10
to 20 mph. There will be an easterly swell of 3 to 4 feet of 8
to 9 seconds with breaking waves of 2 to 3 feet. This will
generally result in a MODERATE risk for the development of
dangerous and life threatening rip currents at the Jersey Shore
and at Delaware Beaches. If winds are a bit stronger, there is
the potential for a HIGH risk at the Jersey Shore.

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

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...Air Quality Alert until midnight EDT tonight for PAZ060>062-
     070-071-101>106.
     Air Quality Alert until midnight EDT Wednesday night for
     PAZ054-055.
NJ...Air Quality Alert until midnight EDT tonight for NJZ001-
     007>010.
DE...None.
MD...None.
MARINE...None.

&&

$$

SYNOPSIS...Gorse/Staarmann
NEAR TERM...DeSilva
SHORT TERM...Gorse/Staarmann
LONG TERM...Gorse/Staarmann
AVIATION...DeSilva/Gorse/Hoeflich
MARINE...DeSilva/Gorse/MPS