Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

Home |  Current Version |  Previous Version |  Text Only |  Print | Product List |  Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
730
FXUS61 KPHI 182254
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
654 PM EDT Fri Jul 18 2025

.SYNOPSIS...
High pressure will remain in place across the area today. A
weak disturbance will pass through late Saturday. A cold front
will approach from the northwest on Sunday, clearing the region
by Sunday night. High pressure will bring tranquil conditions to
the area through mid-week, before the pattern begins to become
slightly more unsettled.

&&

.NEAR TERM /THROUGH SATURDAY/...
Through the forecast period, surface high pressure will shift
from NY state eastward into the Atlantic. The cold front that
went through last night and settled to our south will slowly
lift back north as a warm front. In the mid-levels, a zonal flow
will be the prominent feature.

For tonight...

As a result of the said front and some shortwave energy, we
can`t rule out some showers and thunderstorms across the
Delmarva starting late this afternoon/evening. With lift and
instability at a minimum, SPC has this area in just the General
category. So there`s a low chance of any severe through the
night, even as PoPs increase northward up to about Philadelphia.

Dewpoints, which dropped today, will remain in the 50s across
our northern zones tonight. They`ll also remain in the 60s to
around 70 across the remainder of the region. Overnight lows
will be in the 50s across the far NW and in the 60s to lower 70s
elsewhere.

Winds will be light and variable.

For Saturday...

As the surface high to our north shifts east off the coast of
New England, precipitation chances will increase across most of
our area (PoPs in the 30-60% range) on Saturday. Our far
northern zones look dry at this time. While instability will be
a bit more robust on Saturday compared to today, it still looks
pretty tame. As a result, the severe threat is low. Once again,
the region is just in the SPC General category. However, there
will be ample moisture to work with to support at least some
potential for excessive rainfall. Hence, WPC has us in a
Marginal Risk.

Dewpoints will push upward on Saturday, but high temperatures
look similar to today due to all the clouds that are expected.

Winds will be SE 10 mph or less.

&&

.SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY NIGHT/...
Scattered showers could continue through Saturday night across
the area, though it currently does not appear that this activity
will be widespread. While some elevated instability could allow
for a rumble of thunder or two, severe weather is not expected.
Some of the showers could produce heavy rainfall, but any
residual flooding concerns should diminish during the overnight
hours. Mostly cloudy skies will persist across the entire area,
and lows are expected to range from the upper 60s to lower 70s.

There will likely be a lull in shower activity Sunday morning
and into the early afternoon hours. During this lull, at least
partial clearing is expected, with most of the area warming into
the mid 80s to near 90. With dewpoints in the low-mid 70s, heat
indices are expected to rise into the mid 90s across most of
eastern PA and northern NJ, with upper 90s in far southern NJ
and the Delmarva. As of right now, it appears that heat
headlines won`t be needed as the area should remain below
criteria, but it will still feel fairly oppressive.

Sunday afternoon and into the evening, a cold front is expected
to approach from the northwest and pass through the area. This
front, combined with larger scale ascent from trough axis
passing to the northeast, should be enough to trigger isolated
to scattered showers and thunderstorms. As mentioned, at least
partial clearing should allow for filtered sunshine and strong
surface heating, which will steepen low-level lapse rates and
allow for some instability to be present. Deep layer shear will
support storm organization. While questions remain, at least
some severe potential is apparent across the area ahead of the
cold front. Should strong storms materialize, heavy rain and
local flooding could also become concerns.

Storm chances will diminish from northwest to southeast across
the area Sunday evening into Sunday night with the frontal
passage, which will also be ushering in cooler and drier air.
Lows Sunday night could fall into the upper 50s for the Poconos,
the mid 60s for most of eastern PA and inland NJ, and near 70
along the NJ coastal strip and portions of the Delmarva.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
As surface high pressure builds into the area Monday,
seasonable to slightly below normal temperatures are expected,
along with partly to mostly clear skies. Afternoon highs should
generally be in the low-mid 80s. With the cold front having
removed the very moist airmass from our area, Monday looks to be
the most pleasant day the area has seen in at least a few
weeks. For those of us now accustomed to the oppressive heat,
Monday night could feel almost chilly, with lows in the mid 50s
across northeastern PA and northern NJ, low-mid 60s across
southeastern PA, inland NJ and the Delmarva, and upper 60s near
the coast.

Tuesday looks very similar to Monday, with mostly clear skies,
light winds, and temperatures in the low-mid 80s. Temperatures
Tuesday night will likely be a couple of degrees warmer areawide
than Monday night as a warming and moistening trend begins.
Bottom line- compared to the pattern we have had in place for
the past few weeks, Monday and Tuesday look to have great
weather.

Wednesday through Friday will likely feature a continued
warming and moistening trend. By Friday, temperatures will
likely once again be above average, with the potential for high
humidity to make another appearance as well. In addition, while
no major storm systems are expected, the overall pattern will
likely become slightly more active during this period, with
isolated storm chances returning Thursday and Friday.

&&

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

Tonight...Prevailing VFR conditions expected. Winds light and
variable. Can`t rule out a brief restriction associated with an
isolated SHRA/TSRA late tonight. This would exclude KABE, KRDG,
and KTTN. Due to the isolated nature of the precip, it was left
out of the TAFs for tonight. High confidence of the overall
pattern, but lower confidence that any terminal will see a
SHRA/TSRA due to the isolated nature of the precipitation.

Saturday...Primarily VFR with sub-VFR conditions possible in any
showers and thunderstorms. The coverage of SHRA/TSRA looks
isolated to widely scattered throughout the day and was only
introduced as VCSH given the uncertainty and isolated nature of
the precip. Winds becoming SE 10 kts or less. Moderate
confidence.


Outlook...

Saturday night through Sunday...Mainly VFR. Periods of sub-VFR
conditions will be possible in scattered showers and storms.

Sunday night through Wednesday...VFR. No significant weather
expected.

&&

.MARINE...
Tonight...Sub-SCA conditions expected. SE winds mainly 10 kts
or less. Seas 2 to 3 feet. Can`t rule out a shower or
thunderstorm south of Barnegat.

Saturday...Sub-SCA conditions expected. SE winds 10 to 15 kts.
Seas 2 to 3 feet. Can`t rule out a shower or thunderstorm south
of Barnegat in the morning, and then all the waters in the
afternoon.

Outlook...

No marine headlines anticipated. Winds are expected to remain
below 25 kt with seas below 5 ft. Scattered showers and storms
will be possible Saturday night through Sunday.

Rip Currents...

For Saturday, south to southeast winds around 5-10 mph with
breaking waves of 1-2 feet with a period of 7-8 seconds. As a
result, there is a LOW risk for the development of dangerous and
life threatening rip currents at the Jersey Shore and Delaware
Beaches.

For Sunday, southwest winds around 5-10 mph with breaking waves
of 1-2 feet with a period of 7-8 seconds. As a result, there is
a LOW risk for the development of dangerous and life threatening
rip currents at the Jersey Shore and Delaware Beaches.

Rip currents occur often in the vicinities of jetties and piers
and the speed of the currents are generally maximized at low
tides.

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

&&

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

&&

$$

SYNOPSIS...Cooper
NEAR TERM...Kruzdlo
SHORT TERM...Cooper
LONG TERM...Cooper
AVIATION...Cooper/Guzzo/Kruzdlo
MARINE...AKL/Cooper/Kruzdlo