842
FXUS61 KPHI 281625
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
1225 PM EDT Sat Jun 28 2025

.SYNOPSIS...
A warm front to our south and west will gradually lift northward
today. It will be followed by a weak cold front stalling nearby
early Sunday. The front then shifts northward as a warm front
Monday followed by a cold front later Tuesday. High pressure
builds closer later Wednesday into Thursday before settling over
our area on Friday.

&&

.NEAR TERM /THROUGH SUNDAY/...
A warm front will move northward across the area slowly today.
The low clouds and scattered showers will continue until the
front passes later this morning and into the afternoon.
Following the front skies will become partly/mostly sunny from S
to N across the area. This will cause temps to jump into the 80s
for many areas today. The warmth and humidity will contribute to
more scattered showers/tstms for the mid/late afternoon and into
the evening. The SPC has indicated that a Marginal risk for
severe weather will be around the area today. Damaging winds
with any tstm are possible. Highs will be mostly mid/upper 80s
for S/E areas and low 80s N/W. Rain chances haven`t changed
much since yesterday with likely pops N/W and chance pops for
the Delaware Valley and S/E.


Tonight the weak cold front will cross the area and it will
continue to trigger some scattered showers/tstms as it passes.
There is still a potential for some gusty damaging winds with
any thunderstorm this evening as the front passes. As the night
continues, the instability will diminish and coverage and
intensity of any convection will be reduced as well. Patchy fog
will develop in areas that receive rains today. Lows will not be
that cool with the weak cold air advection behind the front.
Temperatures will only fall into the low/mid 70s for
Philadelphia, south NJ and Delmarva. Up across the NW counties,
the lows will be in the low/mid 60s.

&&

.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
Some showers over the southern half of the area remain possible
through the night on Sunday, but the majority of the region
should be dry. Still muggy overnight though with lows in the mid
to upper 60s and low 70s.

As we go through Monday, an upper-level trough across the
Midwest and adjacent Canada is forecast to shift eastward and
amplify some as it approaches the Northeast. A front warm lifts
north across our area on Monday. A few showers or thunderstorms
are possible with the northward movement of the warm front, with
the greatest chance (40-60 percent) mainly across south and
western parts of our forecast area. Temperatures will make a
run at 90 degrees for many areas and with dew points on the
rise, heat indices will also be on the increase. As of now, the
forecast heat indices are just below Heat Advisory criteria
(even for the the I-95 urban corridor, Wilmington to
Philadelphia to Trenton, where the criteria is lower through
June 30th). Showers and scattered thunderstorms continue into
Monday Night with the warm front lifting north. Again, looking
muggy and mild with lows in the mid to even upper 70s over
Delmarva.

For Tuesday...An upper-level trough is forecast to shift
eastward and amplify some as it overspreads the Northeast and
Mid-Atlantic. This will drive a cold front across our region
later Tuesday. An uptick in the shear is forecast, especially
across Pennsylvania and New Jersey where the stronger mid level
flow is forecast to be. Moderate instability may develop and if
this overlaps with the greater shear, a favorable area for
severe thunderstorms (damaging winds) may develop Tuesday
afternoon and/or early evening. The details will depend on the
magnitude of the shear and instability as well as the timing of
the cold front and upper-level trough axis. 12z suite of
guidance continues to look favorable for some severe weather
though and through the extended, this will be the day to watch.
Temperatures are forecast to top out between 85-90F for much of
the region, although if cloud cover and convection hold off
long enough the highs could be a little higher than forecast.
While it will be rather humid, extreme heat is currently not
forecast.


&&

.LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/...
Summary...Some showers and thunderstorms to start, otherwise no
extreme heat forecast.

Synoptic Overview...An upper-level trough is forecast to move
into much of the East by Tuesday Night. This trough looks to
become reinforced as it remains across much of the East through
the end of next week. At the surface, a cold front moves
offshore by Tuesday Night, then high pressure builds closer
later Wednesday into Thursday before settling over our area on
Friday.

For Tuesday Night, the cold front pushes offshore, with the last
of the showers and thunderstorms moving off the coast by
midnight or so. Lows should be a few degrees cooler than the
previous nights, with upper 60s/low 70s expected.

For Wednesday and Thursday...The upper- level trough across the
Northeast and Mid- Atlantic may tend to sharpen again as
additional energy rounds its base. The cold front should be
south and east of our area to start Wednesday, and while
temperatures do not look to drop much, the dew points are
forecast to lower some in the wake of the cold front. Despite
the presence of the upper-level trough, less in the way of
deeper moisture should keep the instability lower as well. Given
surface high pressure building closer to our area with time,
the chance for any showers and thunderstorms at this time is
little to none.

For Friday...The upper-level trough is forecast to still be in
place with weak surface high pressure becoming more established
over our area. The return flow up the Ohio Valley will increase
the low-level warm air advection with a northeastward moving
warm front. The forcing for this, as of now, looks to remain
well to our west and therefore little in the way of shower
chances. Daytime temperatures in the 80s for most, and the dew
points are forecast to be in the low to mid 60s. Overall, looks
like a nice forecast for the 4th of July. Nice weather should
continue into the holiday weekend.

&&

.AVIATION /16Z SATURDAY THROUGH WEDNESDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY and surrounding areas.

Today... Low CIGS and some reduced VSBYs too (especially
KACY/KMIV) will continue into the morning as a slow moving front
crosses the area. While improving conditions are expected
today, the exact time of the categories is somewhat uncertain, I
have generally kept the TAFS (at 06Z) similar to the previous
ones since the guidance seems to support the slow improvement
trends. Scattered showers thru the day and a few tstms during
the afternoon. Low/medium confid overall.

Tonight... Scattered showers and tstms this evening will bring
localized lower CIGS/VSBYs with low-end MVFR or IFR possible.
After that, winds will shift to West/Northwest and improving
conditions overnight. VFR is possible by dawn Sunday at KPHL and
nearby sites too. Medium confid overall.

Outlook...

Sunday Night...VFR. No significant weather.

Monday through Monday Night...Primarily VFR. Restrictions
possible though with scattered showers and thunderstorms
(30-50%).

Tuesday through Tuesday Night...Restrictions likely (60-80%)
with showers and thunderstorms moving through, mainly in the
afternoon.

Wednesday through Thursday...VFR. No significant weather.

&&

.MARINE...
Winds will veer from SE early this morning to SW by late afternoon
and into the evening. After that, winds will further switch to West
Sat night. Winds and seas will remain below SCA conditions as a warm
front crosses the waters today and tonight. Seas on the ocean will
be mostly around 3 to 4 ft while 1 to 2 ft waves will be across
Delaware Bay. We`ll continue with the Dense Fog Advisory for the
waters this morning and mention scattered showers/tstms for today
and tonight.

Outlook...

Sunday Night through Wednesday...No marine headlines expected.
Some showers and thunderstorms possible (50-70%) later in the
day on Tuesday and into Tuesday Night.

Rip Currents...

For today, the flow turns southerly so there will be less of an
onshore component however the seas will continue to be around 3
to 4 feet with a lingering onshore swell. For this reason,
we`ll continue with a MODERATE risk for the development of
dangerous rip currents for the NJ Shore and Delaware Beaches.

For Sunday, seas lessen some and winds become more variable,
however the period will increase to around 9 seconds with
breaking waves around 2 to 3 feet. Thus, we`ll keep a MODERATE
risk for the development of dangerous rip currents for the NJ
Shore and Delaware Beaches.

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

&&

.TIDES/COASTAL FLOODING...
With onshore flow decreasing today, no further widespread tidal
flooding is expected. Only spotty minor tidal flooding will be
possible with tonight`s high tide along the Delaware Bay and
tidal Delaware River.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...Heat Advisory until 8 PM EDT this evening for PAZ070-071-102-
     104-106.
NJ...Heat Advisory until 8 PM EDT this evening for NJZ015-017>019.
DE...Heat Advisory until 8 PM EDT this evening for DEZ001.
MD...None.
MARINE...None.

&&

$$

SYNOPSIS...Gorse/Hoeflich
NEAR TERM...OHara
SHORT TERM...Gorse/Hoeflich
LONG TERM...Gorse/Hoeflich
AVIATION...Hoeflich/OHara
MARINE...AKL/Hoeflich/OHara
TIDES/COASTAL FLOODING...AKL