608
FXUS61 KPHI 150950
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
550 AM EDT Mon Jun 15 2026

.WHAT HAS CHANGED...
Updated Aviation section for 12z TAFs.

&&

.KEY MESSAGES...
1. Another round of minor coastal flooding is expected
with the Monday evening high tide cycle along the Atlantic coast and
Delaware Bay.

2. High pressure building in will bring fair weather
with seasonable temperatures and comfortable humidity levels through
Tuesday.

3. Some severe thunderstorms possible Thursday afternoon and
evening.

&&

.DISCUSSION...
KEY MESSAGE 1...Another round of minor coastal flooding is expected
with the Monday evening high tide cycle along the Atlantic coast and
Delaware Bay.

Minor tidal flooding occurred once again this past evening in
association with the New Moon that just occurred Sunday. As we
remain near the New Moon, at least one more cycle of widespread
minor coastal flooding is expected with the Monday evening high
tide cycle along the Atlantic coast and the Delaware Bay. New
Coastal Flood Advisories have been issued as a result. There may
also continue be some back bay flooding even this morning
around Barnegat Bay so we`ve ran the Coastal Flood Advisory for
Ocean County starting this morning and going right to 2 AM
Tuesday.

Beyond Monday, tides will continue remain at least somewhat elevated
heading into midweek but will generally trend lower with each
cycle.


KEY MESSAGE 2....High pressure building in will bring fair weather
with seasonable temperatures and comfortable humidity levels through
Tuesday.

A cold front will be pushing offshore through early this morning
with a much drier airmass build in behind it as high pressure moves
into the eastern CONUS. Expect mainly sunny to partly cloudy skies
for Monday and Tuesday with low humidity levels and highs generally
in the upper 70s to near 80. Monday will be a bit breezy with NW
winds gusting to around 20 mph at times with lighter winds for
Tuesday.


KEY MESSAGE 3...Some severe thunderstorms possible Thursday
afternoon and evening.

An upper-level trough centered over south-central Canada is forecast
to strengthen eastward and also southward across the Great Lakes to
end the week. A strong shortwave rounding the base of this trough
may result in a portion of it taking on a negative tilt across the
eastern Great Lakes and toward New England late Wednesday and
Thursday. This feature is a bit stronger in the ECMWF solution,
while the GFS ensembles are mostly a little weaker. A deepening
surface low will accompany it and track across the eastern Great
Lakes and into adjacent Canada during Thursday. A strong cold front
will then arrive into our area Thursday afternoon or Thursday
evening.

As the synoptic pattern evolves, the flow will increase out of the
south and southwest. This will advect deeper moisture northward, and
in tandem with strengthening warm air advection will lead to
increased instability during the day Thursday. In addition, a strong
mid to upper level jet is forecast to extend eastward from the
eastern Great Lakes. While the core of the 500 mb jet (80-100 knots)
is forecast to remain mainly northwest of our area, 40-70 knots of
flow at 500 mb is still forecast across our area Thursday afternoon
into the evening. This increased flow will result in greater shear
magnitudes. While there remains some timing differences among the
guidance regarding the main features, the consensus is that enough
instability should overlap with the stronger shear along with
incoming stronger forcing. As a result, there continues to be some
severe thunderstorm potential Thursday afternoon and evening. As of
now, locally damaging winds are the primary threat especially if
convection develops into a squall line. However if shear and
instability ends up being even greater, than all severe thunderstorm
hazards may come into play especially if the mode is discrete for a
time. The details remain much less certain at this time range given
the typical uncertainty with instability and the thermodynamic
profiles. The forecast synoptic setup however with a deepening
surface low tracking to our northwest with strong flow within a
warmer and more moist environment suggests some risk for severe
thunderstorms. In addition, the main trough may end up arriving on
Friday with some additional chances for showers and some
thunderstorms.

The I-95 corridor and the coastal plain (away from the immediate
coast) looks to be the hottest during Thursday ahead of the
convection, with the heat indices potentially getting very close to
100 degrees.

&&

.AVIATION /09Z MONDAY THROUGH FRIDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY and surrounding areas.

Today...VFR with a few/scattered clouds in the afternoon.
Northwest winds around 10-15 kt, occasionally gusting up to 20
kt. High confidence.

Tonight...VFR. NW winds diminishing to 5-10 knots around sunset
and then to 5 knots or less overnight. High confidence.

Outlook...

Tuesday...Mainly VFR.

Wednesday...Some sub-VFR conditions with a few showers or a
thunderstorm possible.

Thursday...A period of sub-VFR conditions probable in the afternoon
and evening as showers and some thunderstorms increase.

Friday...Some showers and thunderstorms may linger with areas of sub-
VFR conditions possible at times.

&&

.MARINE...
The Small Craft Advisory was allowed to expire but winds will be
a bit breezy across the waters through this morning with a brief
period of 20-25 knot gusts possible from around day break
through the early part of the morning. Otherwise, no marine
headlines expected through Monday night. Expect seas generally
around 2-4 feet.

Outlook...

Tuesday through Wednesday...The conditions are anticipated to
be below Small Craft Advisory criteria.

Thursday...A period of Small Craft Advisory conditions probable.
Southerly wind gusts could near gale force for a time later Thursday.
Some gusty thunderstorms late in the afternoon and evening possible.

Friday...The conditions are anticipated to be below Small Craft
Advisory criteria.

Rip Currents...

For Monday, winds become northwest 10-20 mph with a continued
medium southerly swell of 6-7 seconds. With breaking waves 2
feet or less, have gone with a LOW risk for the development of
dangerous rip currents at all beaches.

For Tuesday, winds start northerly before shifting southeasterly,
but only at around 5 mph with a continued medium southerly
swell of 6-7 seconds. With breaking waves 2 feet or less, have
gone with a LOW 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...None.
NJ...Coastal Flood Advisory from 8 PM this evening to 2 AM EDT
     Tuesday for NJZ012>014-021>024-027.
     Coastal Flood Advisory until 2 AM EDT Tuesday for NJZ020-026.
DE...Coastal Flood Advisory from 8 PM this evening to 2 AM EDT
     Tuesday for DEZ002>004.
MD...None.
MARINE...None.

&&

$$

DISCUSSION...DeSilva/Fitzsimmons/Gorse/Hoeflich
AVIATION...DeSilva/Fitzsimmons/Gorse
MARINE...Fitzsimmons/Gorse