678
FXUS61 KPHI 210647
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
247 AM EDT Fri Aug 21 2026

.WHAT HAS CHANGED...
The threat for flash flooding on Saturday afternoon and evening
has increased. WPC added a SLIGHT (2/4) Risk for Excessive
Rainfall south of I-78.

Small Craft Advisory extended through 8 AM.

&&

.KEY MESSAGES...
1. Another round of heavy rain is on the horizon Saturday into
Saturday night, which could bring the next round of flash
flooding to the region. Unsettled weather continues
through Sunday.

2. Fair weather is expected to return for early next week.

&&

.DISCUSSION...
KEY MESSAGE 1...Another round of heavy rain is on the horizon
Saturday into Saturday night, which could bring the next round
of flash flooding to the region. Unsettled weather continues
through Sunday.

Today will be pleasant with a cold front moving offshore with
our region drying out. We will get a brief reprieve from the
muggy conditions and wet weather with a rather pleasant day
expected. Highs get into the upper 70s to low 80s with mostly
sunny to partly cloudy skies.

Our attention now turns to Saturday afternoon and evening. An
area of low pressure will move in from the southwest bringing
another round of heavy rain to the region. PWATs are again
expected to get near 2" mark with model soundings showing a tall
and skinny CAPE profile. Warm cloud layers also will be over 10k
feet AGL, indicating that any storms that move through will be
quite the efficient rainfall producers. We are starting to get
into range of the CAMs as well. Guidance is all over the place
regarding the placement of the axis of heaviest rainfall, but
some of the QPF numbers are a bit concerning. Both the NAM and
the HRRR have bullseyes over 4" for different parts of the area.
Additonally, most areas yesterday saw over an inch of rain,
with the highest amounts of 4 to 6". So, we are quite
saturated, making it easier to flood in most spots. Will have to
see if guidance later today starts to hone in on where the
heaviest rain will fall before considering any Flood Watches.
However, WPC has added a Slight (2/4) Risk for Excessive
Rainfall for most of area - south of I-78. The risk is certainly
there for more flash flooding.

In terms of the severe weather risk, parameters (shear,
instability, moisture, forcing) are all lower compared to what
we saw yesterday. While a strong to severe thunderstorm can`t be
ruled out completely, the threat for damaging
winds/tornadoes/hail is much lower compared to what we saw
Thursday.

Some showers could linger through Sunday on the backside of the
low but not expecting anything significant through the day.

KEY MESSAGE 2...Fair weather is expected to return for early
next week.

More zonal flow with some subtle ridging moves in for the first
half of the week. At the surface, high pressure will mainly be
in control, resulting in dry and tranquil weather through
Wednesday. Temperatures should be seasonable through this
stretch. Another frontal system looks to move in towards
Thursday-Friday, but too early to speculate on specific impacts.

&&

.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY and surrounding areas.

Today...VFR conditions expected at the Lehigh Valley terminals
as stratus has cleared out. MVFR CIGs expected to linger for the
next couple of hours but should break by 10z-12z at the I-95
terminals and 14z-17z for KMIV/KACY. VFR at all terminals once
the MVFR CIGs lift. Northerly winds around 5 to 10 kt will
become more northeasterly as the day goes on. A sea-breeze
should develop late in the afternoon, resulting in more easterly
winds at KACY/KMIV.

Tonight...Primarily VFR. Some MVFR stratus possible (20-30%
chance) later in the night as another system approaches, but
more widespread restrictions should hold off until daybreak
Saturday. Winds generally light and 5 kt or less, favoring an
east/southeast direction. Moderate confidence.

Outlook...

Saturday through Sunday...Restrictions likely with scattered
showers and thunderstorms moving through at times. Saturday
evening into Saturday Night and Sunday afternoon currently are
the periods that have the highest chance for rain/thunderstorms.

Sunday Night through Tuesday...VFR. No significant weather.

&&

.MARINE...
A Small Craft Advisory is in place for all marine zones through
8 AM as winds near 25 kt have been observed on the waters.

Once the SCA expires, sub-SCA conditions expected through
tonight. Winds out of the east/northeast around 10 to 15 kt and
seas 2 to 4 feet.

Outlook...

Saturday through Tuesday...No marine headlines expected.
Widespread showers and thunderstorms expected on the waters
Saturday afternoon through Saturday Night.

Rip Currents...

For today, a MODERATE Risk for rip currents is in place for
Ocean and Monmouth County, where north/northeast winds around
10 to 20 MPH are expected with breaking waves around 2 to 3
feet. An onshore swell with a dominant period of 9 seconds will
also add to the rip current risk. For the southern NJ shore and
Delaware Beaches, winds will be a bit less with slightly lower
breaking waves. This will result in a LOW risk for rip currents
in these locations.

For Saturday...onshore winds around 10 MPH and multiple swell
groups (one of which has a 12 to 14 second period) will result
in a MODERATE risk for rip currents at the Jersey Shore.
Breaking waves will also be around 2 to 3 feet. For the Delaware
Beaches, winds should be lower with lower breaking waves,
resulting in a LOW risk for rip currents.

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

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...None.
NJ...None.
DE...None.
MD...None.
MARINE...Small Craft Advisory until 8 AM EDT this morning for ANZ430-
     431-450>455.

&&

$$

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