177
FXUS61 KPHI 212341
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
741 PM EDT Tue Jul 21 2026

.WHAT HAS CHANGED...
Aviation section updated for 0z TAFs.

The Tornado Watch has been cancelled for our eastern PA and
northern NJ zones.

&&

.KEY MESSAGES...
1. There continues to be an elevated risk for severe thunderstorms
and flash flooding this evening and Wednesday, with the greater
risk through this evening.

&&

.DISCUSSION...
KEY MESSAGE 1...There continues to be an elevated risk for severe
thunderstorms and flash flooding this evening and Wednesday,
with the greater risk through this evening.

As of early this evening, there are still strong to severe
storms ongoing across portions of Delmarva and southern NJ.
Farther north and northwest over eastern PA northern NJ storms
have exited and the threat for additional severe weather has
diminished. For this reason, we cancelled the Tornado Watch for
these areas while farther south the watches remain in effect.

Storm evolution will remain chaotic this evening with
additional storms likely over Delmarva and southern NJ. There
will continue to be a threat for severe weather, including
tornados, along with flash flooding. The threat of severe
weather should start to diminish by the second half of the
evening while the threat for flash flooding could linger into
the overnight before the cold front arrives from the west and
pushes all the convection towards the coast by around 2 AM or
so. During the rest of the overnight hours, convection may
persist mainly across the southern Delmarva as the frontal
boundary stalls across the region. The flash flood guidance for
this region is not as sensitive to excessive rainfall, but will
still bear monitoring through the early morning hours.

On Wednesday, the cold front will sag farther south and east and
depending on how quickly this clears our area there will be some
showers and thunderstorms, especially as additional shortwaves move
through the flow within the upper-level trough overhead. This looks
to be more concentrated across southern New Jersey to Delmarva but
could extend into the I-95 corridor for a time. There is some severe
weather risk mainly near and south/east of the I-95 corridor with
locally damaging wind gusts the main threat. The greater instability
and shear looks to reside across Delmarva on southward, where a
little higher severe thunderstorm risk is indicated. Some locally
excessive rainfall is possible with some local flash flood risk,
however this looks to be less compared to today given the shift
farther south and more into the coastal plain. Once the front moves
away by later Wednesday, it turns drier for Thursday/Friday and
right into the weekend.

&&

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

Tonight...Still some showers and thunderstorms around this
evening mainly from around Philly southward. In any of these
showers conditions may still drop to MVFR or even IFR...best
chances for this at MIV and ACY. Otherwise, widespread showers
diminish by the overnight period with MVFR cigs likely affecting
most sites by around the 04-07z time frame. Winds generally
southwest 10 to 15 knots but locally strong and variable winds
possible in any storms.

Wednesday...Once morning clouds clear by around 14Z, should
have prevailing VFR conditions. However, temporary MVFR or even
IFR conditions will be possible with showers and storms. The
highest risk of showers and storms is at KACY, but it is
possible the storms will be south of all TAF sites. Southwest
winds around 10 KT with some gusts of 15-20 knots possible.
Moderate confidence.

Outlook...

Thursday through Saturday...VFR.

&&

.MARINE...
Small Craft Advisory conditions for all coastal waters through
Wednesday evening. SCA conditions do subside though overnight
on Delaware Bay. Gusty thunderstorms probable mainly this
evening and into tonight.

Outlook...

Wednesday...Small Craft Advisory remains in effect for the ocean
zones.

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

Rip Currents...

For the rest of today, southerly winds of 15-25 mph with either a
shore parallel or slight onshore flow expected depending on
location. Breaking waves of 2-4 feet will result in more energy
within the surf zone. As a result, maintained a MODERATE risk for
the development of dangerous rip currents at all beaches.

For Wednesday, winds turn more southwesterly but still 10-20 mph.
However, breaking wave heights are expected to increase, with
breaking waves in the surf zone as high as 5 feet possible. Still a
7 second period though which will mitigate the rip current threat
some. However, will continue with a MODERATE risk for the
development of dangerous rip currents at all beaches.

For Thursday, winds come around to the northeast and will generally
be 15 to 20 mph. Breaking waves are expected to be around 2-4 feet
with a 7 second period. With the onshore component of the wind and
multiple swell groups expected, expecting a MODERATE risk for the
development of dangerous rip currents at all beaches.

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

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...Flood Watch until 2 AM EDT Wednesday for PAZ070-071-101>106.
NJ...Flood Watch until 2 AM EDT Wednesday for NJZ008>010-012>015-
     017>019.
DE...Flood Watch until 2 AM EDT Wednesday for DEZ001.
MD...None.
MARINE...Small Craft Advisory until 6 AM EDT Wednesday for ANZ430-431.
     Small Craft Advisory until 2 AM EDT Thursday for ANZ450>455.

&&

$$

DISCUSSION...Fitzsimmons/Gorse/MJL
AVIATION...Fitzsimmons/Gorse/Johnson
MARINE...Gorse/Hoeflich/MJL