737
FXUS61 KPHI 252106
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
506 PM EDT Tue Jun 25 2024

.SYNOPSIS...
A weak ridge of high pressure across the region will move east
overnight. Low pressure and its associated front will move
towards eastern Pennsylvania later Wednesday and then move
offshore by Thursday morning. More high pressure moves in for
the last past of the week. Another disturbance will be across
the area for the upcoming weekend.

&&

.NEAR TERM /THROUGH WEDNESDAY/...
Dry weather will continue for the remainder of this afternoon
with only some high level clouds blowing off the convective
complex moving across the Ohio River Valley. As the short
wave/vorticity impulse associated with this convective complex
moves across our area later this evening and overnight, there
could be some showers move across portions of northeast
Pennsylvania and northern New Jersey. However, most areas are
expected to remain dry as this activity will mostly dissipate
before reaching our area.

Wednesday is expected to be another hot and humid day across
much of the area as southwest/return flow will lead to
increasing temperatures and dewpoints across the area. We have
kept the Heat Advisory in place where it was before as
temperatures north and west of the advisory may stay suppressed
enough with increasing clouds, and they may stay on the western
side of a pre-frontal trough that develops and moves across the
area. Heat Index values across the advisory area are expected to
reach the 100-105 degree range. Areas south of the advisory are
expected to remain below the 105 heat index criteria; although
it will be quite hot and humid there.

In addition to the heat and humidity, there remains the
potential for a round of showers and thunderstorms during the
afternoon hours. There will be plenty of instability across the
area with CAPE values potentially reaching 1000-2000 J/kg, shear
values increase to 25-35 knots, and there will be a short
wave/vorticity impulse moving across the area during the
afternoon that could help enhance the lift along with the pre-
frontal trough. We remain in a slight risk for severe weather
from the SPC, with damaging winds being the main threat due to
DCAPE values in the 1000-12000 J/kg range although there will be
a chance for hail, and an isolated tornado cannot be ruled out.
Heavy rainfall will also be possible with any thunderstorms as
PW values approach 2 inches, but they should be progressive
enough to preclude a flash flood threat.

&&

.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
Showers and thunderstorms will be across the area Wednesday
night as the low and front pass through. The activity will end
from west to east during the overnight hours with some showers
possible along the shore areas around sunrise. Clouds will
remain most of the night most areas. Lows will drop into the low
60s across the far NW areas where cold air advection will begin
before Thu. morning. Other areas will remain mild/humid with
lows mostly mid/upper 60s. Winds will turn W/NW overnight and
remain around 10 mph with some gusts 20-25 mph early.

For Thursday and Friday, fair weather is expected as high
pressure arrives from the Midwest Thu and crests over the area
Fri. Dry weather with seasonable temperatures are expected.
Highs will favor the mid/upper 80s for both days. Humidity
levels will be comfortable by in large with dew points in the
60s Thu and 50s for Fri.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
The closing days of June, this weekend, will feature summerlike
conditions more typical of July with `low-end` hot temperatures
and ample humidity. While the heat builds there will also be
opportunities for showers and a few tstms too as shortwave
energy and a few surface front move towards the area from the
Great Lakes area. The activity will be scattered however and
while it may affect both days, the overall amount of time with
rains will not be that great. A higher chance for rains is
expected Sunday, mostly in the morning and early afternoon, so
likely pops are in the grids while other areas have chance pops.
High temperatures will be above normal with upper 80s/low 90s
across most spots. Cooler highs will be found at the shore and
southern Poconos. The overnight lows will be mild and humid.

As July arrives, cooler and drier air drops down from the N/W
areas and brings more temperate conditions. Highs Mon/Tue will
be in the low/mid 80s most areas with comfortable humidity
levels too. Not much in the way of disturbances for the new
week, so pops will be low and skies should be mostly sunny both
Mon/Tue.

&&

.AVIATION /21Z TUESDAY THROUGH SUNDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY and surrounding areas.

Rest of today-Tonight...VFR conditions expected. South-
southwest winds 5-10 knots with gusts 15-20 knots this
afternoon.

Wednesday...Mostly VFR conditions expected. Chance of showers
and thunderstorms in the afternoon which may lead to lower
conditions. Southwest to west winds 5-10 knots, occasional gusts
15-20 knot sin the afternoon. Stronger winds in thunderstorms.

Outlook...

Wed night... Showers and tstms with lower CIGS/VSBYS will be
moving through this period. MVFR or possible IFR conditions with
the rains. Conditions improve late from West to East.

Thu thru Friday... Mostly VFR expected.

Sat/Sunday... VFR most of the time, but scattered showers/tstms
with lower conditions at times. Most likely Sat evening thru
Sunday morning.

&&

.MARINE...
Tonight-Wednesday...Small Craft Advisory remains in effect for
the Atlantic Ocean waters tonight through Wednesday due to
increasing winds and waves. Tstms expected Wed
afternoon/evening.

Outlook...

Wed night... SCA conditions early with showers/tstms over the
waters. Conditions improve late with winds and seas diminishing.

Thu thru Fri night... sub-SCA expected. Fair weather.

Sat/Sat night/Sunday... Scattered showers tstms Sat becoming
more numerous Sunday. Low-end SCA winds and seas developing Sat
afternoon and lasting into the overnight.

Rip Currents...

Wednesday...South to southwest winds increasing to 15-20 mph,
with breaking waves building to 3 to 5 feet along the NJ shore
and 2 to 3 feet along the DE beaches. With winds parallel to
slightly onshore, have upgraded to to a HIGH risk of rip
currents for the Jersey Shore but kept a MODERATE risk for the
Delaware beaches.

Thursday...West to northwest winds of 10 to 15 mph in the
morning become variable in the afternoon. Breaking waves will
decline from 2-4 feet early to 1-2 feet late, with lowest along
the DE coast. Thus, went with a MODERATE risk along the Jersey
shore and a LOW risk along the Delaware beaches.

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


&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...Heat Advisory from 9 AM to 9 PM EDT Wednesday for PAZ070-071-
     102-104-106.
NJ...Heat Advisory from 9 AM to 9 PM EDT Wednesday for NJZ010-012-
     013-015-017>020-027.
     High Risk for Rip Currents from Wednesday morning through Wednesday
     evening for NJZ014-024>026.
DE...Heat Advisory from 9 AM to 9 PM EDT Wednesday for DEZ001.
MD...None.
MARINE...Small Craft Advisory until 6 AM EDT Thursday for ANZ450>453.
     Small Craft Advisory from 11 PM this evening to 11 PM EDT
     Wednesday for ANZ454-455.

&&

$$

SYNOPSIS...OHara
NEAR TERM...Robertson
SHORT TERM...OHara
LONG TERM...OHara
AVIATION...OHara/Robertson
MARINE...OHara/RCM/Robertson