Philadelphia, Pennsylvania 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

977
FXUS61 KPHI 101645
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
1245 PM EDT Tue Jun 10 2025

.SYNOPSIS...
A cold front is moving through now and will be offshore by
tonight. High pressure builds in for Wednesday, keeping things
quiet and warm for Wednesday and Thursday. A cold front moves in
from the north later on Friday, stalling out near or over the
area for the weekend. Several waves of low pressure ride along
the front bringing unsettled weather for the weekend and start
of next week.

&&

.NEAR TERM /THROUGH WEDNESDAY/...
630 AM...Quick update to mention that we`ve issued a Dense Fog
Advisory for most of our coastal plain zones that includes all
of Delaware as well as southern and coastal NJ north through
Monmouth County. This is in effect until 9 AM.

As of early this morning, a warm front was located over Delmarva
extending eastward off the coast with a cold front extending from
western Maryland south and westward. This is putting SE PA right
near the triple point of a developing wave and there`s an associated
area of showers and thunderstorms moving across our eastern PA
zones.

As we head into the day today, these showers and storms move
into the urban corridor and points S/E through the first part of
the morning with a continuing threat for some localized
flooding...once again, especially for low lying, poor drainage,
as well as urban areas. This leading wave of showers/storms then
moves off the coast by around midday. Beyond this time the main
cold front pushes through the area in the afternoon and while
this could produce some additional showers/storms, they look to
be more isolated to scattered in nature...as in many or even
most places won`t see them. Instability will be increasing with
ML CAPE around 500-1000 j/kg and deep layer shear looks to be
quite strong as well. So it`s possible that any storms that do
develop could be severe it`s really the overall coverage of
storms that remains in question but is trending down with time.
But the upshot of all this is that we`re not expecting
widespread severe weather. Highest POPs for the afternoon still
look to be areas near and south/east of the urban corridor. Most
areas look to see highs getting into the low 80s as partial
sunshine develops by the afternoon. It will remain muggy through
the early afternoon before dew points and humidity levels start
to fall off behind the cold front by later in the day.

For tonight, any lingering showers/storms quickly diminish in
the early evening with otherwise clearing skies and falling
temps and dew points as drier air works in from the west. Lows
by Wednesday morning look to range from the 50s north to the low
to mid 60s south.

&&

.SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY NIGHT/...
High pressure remains in control through the middle of the week,
keeping things dry into Friday morning. We start out with clear
skies and tranquil conditions for Wednesday night with lows
mainly in the low to mid 60s. Warm west/southwesterly flow
strength. Highs around the I-95 corridor as well as interior
southern NJ likely get into the low 90s, and mid to upper 80s
elsewhere. PHL has not recored a 90 degree day yet, which the
first one typically comes in May. NBM probability of highs over
90 for Philadelphia is currently between 60-80%. Humidity won`t
be overly oppressive either and apparent temperatures will only
be a degree or two higher than the actual temperature, with
heat headlines highly unlikely to be needed. A shortwave tries
to dive in on Thursday, which could touch off a few
showers/isolated thunderstorms in the Poconos, but nothing of
significance.

Mostly clear to partly cloudy skies for Thursday night but it
will be mild coming off our likely warmest day of the year.
Overnight lows generally get down into the mid to upper 60s, but
wouldn`t be surprised to see some spots within the urban
corridor fail to fall below 70.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
A cold front sags down from the north on Friday afternoon, stalling
out over the area for the weekend. Several waves of low pressure
will ride along the front, with periods of showers and isolated
thunderstorms expected through the long term. Model guidance tends
to struggle with setups like these, and this case is no different.
Not expecting a weekend washout, but rather periods of rain with a
few thunderstorms mixed in and mostly cloudy skies outside of any
precipitation. Latest NBM seems to target Saturday afternoon and
evening with the highest PoPs (50-70%), which falls in line
with individual deterministic guidance members. PoPs remain in
the grids through the weekend and into next week as the front
lingers. Given the uncertainty of the pattern, would expect
changes as we get closer. However, not expecting any hydro or
severe weather issues as the higher instability will be off to
the south. All in all, just looks like another weekend featuring
rain.

While Friday will be warm with highs in the mid to upper 80s
ahead of the front, temperatures cool off over the weekend.
Things have trended a bit warmer for Saturday as the morning now
looks drier. Highs could get into the low to mid 80s. Sunday
onward looks cooler with highs generally in the 70s.

&&

.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY and surrounding areas.

Today...IFR conditions with periods of LIFR remaining possible
during the early morning, with ceilings gradually improving from
west to east. Showers will be most likely between 10-16Z, with
embedded thunder remaining possible, especially for the I-95
terminals. Most terminals should improve to MVFR by around 16z
or so and then VFR by mid afternoon. Light east wind becoming
west/northwest at 5-10 kt by the afternoon. Expect some gusts in
the afternoon around 15-20 knots. Moderate confidence.

Tonight...VFR. Winds generally out of the west around 5 knots.
High confidence.

Outlook...

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

Friday...VFR to start but restrictions possible later in the day as
a cold front approaches with scattered showers and isolated
thunderstorms moving in.

Friday Night through Sunday...Restrictions expected (70-80%
confidence) at times with low clouds and showers around. Slight
chance of thunder (15%) during the afternoon both Saturday and
Sunday.

&&

.MARINE...
Based on the latest observations and trends, we expanded the
Marine Dense Fog Advisory to include all our Marine zones and
extended it until 9 AM. Expect visibility 1 NM or less. There
will also be some showers/storms over the waters Tuesday, mainly
in the morning. These could produce locally strong winds over
34 knots.

Tuesday night...No marine headlines expected.

Outlook...

Wednesday Night through Saturday...No marine headlines
expected. Showers and isolated thunderstorms possible (40-60%)
on Saturday.

Rip Currents...

For Today...South-southwest winds around 10-15 mph. Breaking
wave heights of 2-4 feet with an increasing southeast swell of
3-4 feet around 6-7 seconds in length. As a result, a MODERATE
risk for dangerous rip currents is now in place for both the
Jersey Shore and Delaware Beaches. We`ll also be within 1 day
of the Full Moon phase, which may allude to stronger than
normal rip currents.

For Wednesday...West-northwest winds around 5-10 mph, becoming
south-southwest in the afternoon. Breaking wave heights of 1-3
feet with a decreasing southeast swell of 2-3 feet around 6-7
seconds in length. As a result, a MODERATE risk for dangerous
rip currents is in place for Ocean, Atlantic and Cape May
County beaches, whereas a LOW risk for rip currents is in place
for Monmouth County and Delaware Beaches. The Full Moon phase
will occur on Wednesday as well, which may allude to stronger
than normal rip currents.

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

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...None.
NJ...None.
DE...None.
MD...None.
MARINE...Dense Fog Advisory until 2 PM EDT this afternoon for
     ANZ450>455.

&&

$$

SYNOPSIS...Fitzsimmons/Hoeflich
NEAR TERM...Fitzsimmons
SHORT TERM...Fitzsimmons/Hoeflich
LONG TERM...Fitzsimmons/Hoeflich
AVIATION...Fitzsimmons/Hoeflich
MARINE...DeSilva/Fitzsimmons/Guzzo/Hoeflich