388
FXUS61 KPHI 131003
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
603 AM EDT Mon Jul 13 2026

.WHAT HAS CHANGED...
Issued an Extreme Heat Watch for the Philadelphia metropolitan
area.

Updated coastal flooding section.

&&

.KEY MESSAGES...
1. Above normal temperatures take over by Tuesday, likely
continuing toward the end of the week. Wednesday will be the
hottest day of the stretch, and an Extreme Heat Watch was issued
for the Philadelphia metro.

2. Late week could be active and unsettled with a chance for
showers and thunderstorms, some of which could be severe.

3. Coastal Flood Advisories have expired. Only spotty minor
tidal flooding is expected with tonight`s high tide.

&&

.DISCUSSION...
KEY MESSAGE 1...Above normal temperatures take over by Tuesday,
likely continuing toward the end of the week. Wednesday will be
the hottest day of the stretch, and an Extreme Heat Watch was
issued for the Philadelphia metro.

A more typical summertime pattern sets up beginning on Tuesday.
Temperatures are expected to get above normal as ridging extends
into the Mid-Atlantic from the west with surface high pressure
strengthening offshore. This will set up warm southerly flow,
allowing the heat and humidity to return. The heat peaks on
Wednesday over the area as temperatures should get well into
the 90s with increasing humidity. Its not out of the question
PHL and a few other sites tag the century mark again, but
nothing like we saw to start July. Humidity will be less as
well. However, heat index values are still projected to get
near 105F or even higher, potentially up to 108F. As a result,
issued an Extreme Heat Watch for the Philadelphia metro area for
Wednesday. Further heat headlines (either Advisory or Warning)
will be needed across more of the area, but the warmest
temperatures and heat indices will be over the urban corridor.

A dry cold front looks to pass sometime late Wednesday which
will knock down temperatures a bit, but medium range guidance
and ensembles indicate above normal temperatures in the upper
80s/low 90s could remain through the end of the week and
potentially into the weekend.


KEY MESSAGE 2...Late week could be active and unsettled with a
chance for showers and thunderstorms, some of which could be
severe.

We are still several days out but we are monitoring the severe
weather setup towards the end of the week and into the weekend.
A strong cold front will slide southward to break the heat
ridge, putting potential for another round of severe weather in
play. The Storm Prediction Center (SPC) has highlighted some of
the area in a Slight Risk (15% chance of severe thunderstorms
25 miles from any point) on Friday. Storms look to be driven by
a strong cold front swinging in from the northwest and with
ample daytime heating and instability, the ingredients are
certainly there for strong to severe thunderstorms and damaging
wind gusts. Timing is uncertain, as some of the latest guidance
is somewhat faster with frontal progression.

In their long term outlook, SPC did mention some small MCS
potential during the day 7 to 10 period as some shortwaves are
likely to ripple through the northwest flow. Again, still
several days out, but we will have to monitor the severe weather
potential for the end of the week and possibly next weekend.

KEY MESSAGE 3...Coastal Flood Advisories have expired. Only
spotty minor tidal flooding is expected with tonight`s high
tide.

All Coastal Flood Advisories have expired. While astronomical
tides are increasing slightly with the New Moon tomorrow, flow
is turning more offshore. Some spotty minor tidal flooding is
likely tonight along the Atlantic coast, Delaware Bay, and tidal
Delaware River, but water levels should remain below Advisory
criteria.

With offshore flow continuing and strenghtening through the
middle of the week, no tidal issues are expected after tonight`s
high tide.

&&

.AVIATION /10Z MONDAY THROUGH FRIDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY and surrounding areas.

Today...VFR. South/Southwest winds around 5 to 10 kt. High
confidence.

Monday Night...VFR/SKC. Light southwest winds 5 kt or less. High
confidence.

Tuesday...VFR. West/southwest winds around 5 to 10 kt. High
confidence.

Outlook...

Tuesday Night through Friday...VFR. Mainly dry though cannot
rule out a few thunderstorms towards the end of the week,
potentially resulting in brief restrictions.

&&

.MARINE...
Sub-SCA conditions expected through Tuesday morning. Winds
generally 10 kt or less starting out of the east/southeast today
and becoming south/southwesterly by tonight. Seas 2 to 3 feet.

Outlook...

Tuesday Afternoon through Tuesday Night...SCA conditions
possible (40-50%) for the New Jersey coastal waters as
south/southwesterly wind gusts could get near 25 kt at times and
seas near 5 feet.

Wednesday through Friday...No marine headlines expected.


Rip Currents...

For today, a single 6 second swell combined with low breaking
wave heights (1 to 3 feet) will result in a LOW risk for the
development of rip currents for all locations. Southeast flow
remains but winds should be light, generally around 10 MPH or
less.

For Tuesday, flow turns offshore with a 7 to 9 second period
swell. Wave heights remain around 2 feet as well, resulting in a
LOW risk for rip currents continuing.

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

&&

.CLIMATE...
A brief 1-day spike in temperatures is expected, with highs
likely to approach records. Here are the records for Wednesday,
July 15:

Allentown/ABE      98 in 1995
AC Airport/ACY    100 in 1995
AC Marina/55N      99 in 1995
Georgetown/GED     96 in 2024 and 1993
Mount Pocono/MPO   92 in 1954
Philadelphia/PHL  103 in 1995
Reading/RDG       100 in 1995
Trenton/TTN       101 in 1995
Wilmington/ILG     99 in 1997 and 1995

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...Extreme Heat Watch from Wednesday morning through Wednesday
     evening for PAZ070-071-104-106.
NJ...Extreme Heat Watch from Wednesday morning through Wednesday
     evening for NJZ015-017>019.
DE...Extreme Heat Watch from Wednesday morning through Wednesday
     evening for DEZ001.
MD...None.
MARINE...None.

&&

$$

DISCUSSION...Hoeflich
AVIATION...Hoeflich
MARINE...Hoeflich