Special Marine Warning 50, NWS Philadelphia/Mount Holly

Area Forecast Discussion
National Weather Service Mount Holly NJ
823 PM EDT Fri Jun 12 2026

.WHAT HAS CHANGED...
Severe weather risk and heat risk have ended for tonight.

Updated aviation section for 0Z TAFs.

&&

.KEY MESSAGES...
1. Much less humid on Saturday.

2. Showers and some thunderstorms return Sunday afternoon and
Sunday night, with some severe thunderstorm risk. Cooler and
less humid for the first half of next week.

3. Widespread minor coastal flooding with the evening high tide
cycles Saturday and Sunday along the Atlantic coast, Delaware
Bay, and possibly on the tidal Delaware River.

&&

.DISCUSSION...
KEY MESSAGE 1...Much less humid on Saturday.

A cold front is forecast to move through the region overnight,
which will knock the temperatures down a few degrees and allow
dew points to return to more comfortable levels for the weekend.
Although it will still be hot with high temperatures in the
upper 80s to low 90s over the weekend, dew points will mainly be
in the upper 50s to low 60s. Therefore, heat indicies will not
be far removed from the actual air temperature, thus no heat
headlines are anticipated over the weekend.

KEY MESSAGE 2...Showers and some thunderstorms return Sunday
afternoon and Sunday night, with some severe thunderstorm risk.
Cooler and less humid for the first half of next week.

An expansive upper-level trough across much of eastern Canada
Sunday will gradually shift eastward into early next week. Some
stronger shortwave energy within the southern portion of the
trough will slide across our area later Sunday. A cold front
will also be tied to this feature and that will cross our area
later Sunday afternoon and Sunday evening. The low to mid level
flow will increase some in response to this incoming shortwave
and cold front, which will also increase the warm air advection
and also the low-level moisture advection. At least some of the
guidance shows a rapid moisture return in the lower levels as
the air mass recovers from the substantial drying on Saturday.
This will result in it feeling more humid Sunday, however it is
not expected to be at the levels we currently are experiencing.

The main forecast challenge is the timing, coverage and
intensity of convection with this incoming system. It appears to
be later in the afternoon and at night regarding the timing.
There will be a period of stronger synoptic forcing arriving,
and with the low to mid level flow increasing some the shear
will increase some as well. The amount of instability should be
sufficient enough to support some thunderstorms, however the
magnitude of this will determine the intensity of the
thunderstorms. If sufficient instability can be realized, then
some severe thunderstorms will be possible with damaging winds
the main severe weather threat. Given mostly unidirectional flow
ahead of the cold front, convection should tend to develop into
a couple of clusters or a line, with this potentially more
favorable from about the Philadelphia metro on southward. Some
model forecast soundings show steep low-level lapse rates with
some dry air in the mid levels. The steep low-level lapse rates
would result in higher DCAPE values, which is supportive of an
enhanced wind threat with any stronger thunderstorms.

In the wake of the cold front, a less humid and cooler air mass
overspreads our area through the first half of next week. An
upper- level trough starts to approach on Tuesday and that may
result in a few showers Tuesday and Wednesday, with a greater
chance for some showers and thunderstorms during Thursday.

KEY MESSAGE 3...Widespread minor coastal flooding with the
evening high tide cycles Saturday and Sunday along the Atlantic
coast, Delaware Bay, and possibly on the tidal Delaware River.

A New Moon this weekend will result in higher than normal
astronomical tides. Astronomical tides will generally be 1/2
foot less than minor coastal flooding thresholds, and tidal
departures will be around 1 foot or so. This will result in
widespread minor coastal flooding with the evening and nighttime
high tide cycles Saturday and Sunday, and potentially Monday as
well on the Atlantic coast and Delaware Bay. The tidal Delaware
River and its tributaries could experience some spotty minor
tidal flooding by Sunday night's high tide, and potentially
Monday night too, but generally these astronomical tide driven
flooding events produce more noteworthy impacts for the Atlantic
coasts and Delaware Bay. The highest of the New Moon tides will
be Sunday night and Monday night. Tidal flooding is not
currently expected along the eastern shore of Chesapeake Bay.

&&

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

Tonight...VFR. Westerly winds early will shift to northwest
around 5-10 kt overnight in wake of a cold front. High
confidence.

Saturday...VFR/SKC. West-northwest winds around 5-10 kt. High
confidence.

Outlook...

Saturday night...VFR.

Sunday...Sub-VFR conditions probable for a time due to showers
and some thunderstorms, especially in the afternoon and evening.

Monday...VFR. Northwesterly wind gusts to 20 knots possible.

Tuesday and Wednesday...Some sub-VFR conditions with some
showers possible.

&&

.MARINE...
No marine headlines are in effect through Saturday. Winds shift
northwest tonight in wake of a frontal passage. Northwest winds
will continue through Saturday morning, before transitioning
back to southwest by Saturday afternoon. Seas generally around
2-3 feet, locally up to 4 feet.

Isolated thunderstorms diminishing this evening. Fair weather
is expected on Saturday.

Outlook...

Saturday night...No marine hazards anticipated.

Sunday...A brief period of SmallCraft Advisory conditions are
possible in the afternoon and evening due to wind gusts to 25
knots.

Monday through Wednesday...No marine hazards anticipated.

Rip Currents...

For Saturday, a medium period 8 second swell, offshore winds,
and breaking waves 2 feet or less will result in a LOW risk for
development of dangerous rip currents at the Jersey Shore and
Delaware Beaches.

For Sunday, winds become southerly and increase to around 15-20
MPH. However, with a medium period swell around 8 seconds
continue, breaking waves will be again 2 feet or less, for most
beaches. The exception will be at southern facing beaches in
Cape May and Atlantic counties where breaking waves in the surf
zone will be up to 3 feet as the winds will be most directly
onshore here. Therefore, the risk for the development of
dangerous rip currents will be higher for these beaches, and a
MODERATE risk is currently forecast for these two counties. For
the remainder of the Jersey Shore and the Delaware Beaches, a
LOW risk for the development of dangerous rip currents is
forecast.

Ocean water temperatures are mostly in the mid to upper 60s.

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

&&

.CLIMATE...
Hot air mass is moving out, but some record highs were set.
We've shared the list in the RER products and on social media.
The following record warm low temperatures could still be set if
temperatures remain this high through 1 AM EST (12 midnight
standard time).

Location                   6/12 Record Warmest Low/Year

Allentown                     70/1942
Trenton                       72/2015 & 2017
Atlantic City Airport         73/1973 & 2015
Georgetown                    73/1947, 1973, 1986, & 2017

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...None.
NJ...None.
DE...None.
MD...None.
MARINE...None.

&&

DISCUSSION...AKL/DeSilva/Gorse/RCM
AVIATION...DeSilva/Gorse/RCM
MARINE...AKL/DeSilva/Gorse/RCM

Hazardous Weather Outlook
National Weather Service Mount Holly NJ
517 AM EDT Fri Jun 12 2026

MDZ012-015-019-020-130930-
Kent MD-Queen Annes-Talbot-Caroline-
517 AM EDT Fri Jun 12 2026

This Hazardous Weather Outlook is for northeast Maryland.

.DAY ONE...Today and tonight.

There is a SLIGHT Risk (level 2 out of 5) of severe thunderstorms
today. Hot and humid conditions will continue through today.

.DAYS TWO THROUGH SEVEN...Saturday through Thursday.

There is a SLIGHT Risk (level 2 out of 5) of severe thunderstorms on
Sunday.

.SPOTTER INFORMATION STATEMENT...

Weather spotters are encouraged to report significant weather
conditions according to standard operating procedures.

Staarmann

Preliminary Local Storm Report
National Weather Service Mount Holly NJ
623 PM EDT Fri Jun 12 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0446 PM     Tstm Wnd Dmg     1 NNE Leisuretowne      39.90N 74.70W
06/12/2026                   Burlington         NJ   Newspaper

            Wires down near Big Hill Road in Southampton
            Township. Time estimated from radar.

&&

AKL

Preliminary Local Storm Report
National Weather Service Mount Holly NJ
629 PM EDT Fri Jun 12 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0600 PM     Marine Tstm Wind Harvey Cedars           39.70N 74.14W
06/12/2026  M52 MPH          Ocean              NJ   Mesonet

            NJWxNet Station NJ11 Harvey Cedars.

&&

AKL

Preliminary Local Storm Report
National Weather Service Mount Holly NJ
631 PM EDT Fri Jun 12 2026

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0559 PM     Marine Tstm Wind 1 SSE Bay Side          39.66N 74.21W
06/12/2026  M44 MPH          ANZ451             NJ   Mesonet

            WeatherFlow Station XLBI.

&&

AKL

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