-- Discussion containing changed information from previous version are highlighted. --
883
FXUS61 KPHI 241052
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
652 AM EDT Mon Jun 24 2024

.SYNOPSIS...
A cold front pushes offshore today with high pressure building in
off to the south through Wednesday morning. The heat ramps up on
Wednesday ahead of another strong cold front coming in late
Wednesday. High pressure builds in once the front moves offshore,
and will remain in control through the first half of the weekend
before another frontal system comes in late Saturday/Sunday

&&

.NEAR TERM /THROUGH TONIGHT/...
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The main cold front is still pushing east from eastern PA this
morning and is expected to move offshore in the next few hours.
As a result, while showers and thunderstorms are expected to
dissipate after the front pushes through, we could see one more
round of showers and storms, mainly across the Delmarva and
extreme southern NJ early this morning before the front finally
finishes its trek east.

After the front has moved through the region Monday morning, drier
and cooler air arrives behind it. Clouds will decrease from NW to SE
across the area. Daytime temperatures will be quite a bit cooler for
most areas with mid/upper 70s for the Southern Poconos and Lehigh
Valley areas and low/mid 80s for metro Philadelphia and much of NJ.
A few upper 80s for Delmarva are possible. The dew points will be
much lower, dropping to the mid-50s, with a more comfortable feel to
the air. Winds will be West to Northwest and increase to 10 to 15
mph with gusts to 25 mph at times.

High pressure continues to build in Monday night with mostly clear
skies. NW-WNW winds will maintain a steady breeze overnight, around
5-10 mph. A very cool and comfortable night ahead with lows in the
60s and low humidity.
.
-- End Changed Discussion --

&&

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
High pressure builds in for Tuesday into Tuesday Night. We will
get a little warmer as flow turns more southwesterly and warm
air advection sets up. Temperatures will get into the upper
80s/low 90s, but with dew points in the 50s, it won`t feel
nearly as oppressive as the previous week. Skies will be mostly
sunny and it will be a pretty nice early summer day overall.
Temperatures on Tuesday Night will be a bit on the milder side
as a warm front lifts through and dew points increase ahead of a
hot and humid Wednesday. Looking at upper 60s/low 70s with
increasing clouds.

For Wednesday, a warm and muggy day is on tap as dew points climb to
near 70. Ahead of a cold front, warm, moist air will advect in and
PWATs will surge to near 2 inches. The front approaches as we get
into Wednesday afternoon, and some afternoon and evening showers and
thunderstorms are expected. The setup is not too dissimilar from
what we saw yesterday (similar instability, steep low level lapse
rates, and forcing for example), though with perhaps just a touch
more shear. So there is some severe weather potential with the main
threat being damaging wind gusts. With such a moist airmass in
place, cannot rule out some localized flash flooding, but would
expect storms to be moving at a steady pace based off some of the
model soundings. With the front coming in later in the day, it will
allow temperatures to soar into the low to mid 90s, again similar to
yesterday. Heat indices will get near triple digits and a Heat
Advisory may be needed, especially for the urban corridor.  Showers
and thunderstorms should taper off into the night, but
rain chances remain until the front passes. Temperatures will
drop into the upper 60s/low 70s on Wednesday Night.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
Relatively quiet in the long term with seasonable temperatures
overall.

The cold front moves offshore by Thursday, ushering in a more
comfortable airmass with lower dew points. There could be some
lingering showers/thunderstorms near the coast in the morning as the
front passes, but it should be mainly dry day, especially along and
west of the I-95 corridor. Upper level ridging begins to move in
with an expansive area of surface high pressure slowly sliding by
just to the north. This will result in a few nice days through the
first half of the weekend with dry weather and seasonable
temperatures (mid to upper 80s for highs).

Another frontal system looks to move in somewhere in the late
Saturday/Sunday window, which will bring another chance from some
showers and thunderstorms. Still a lot of timing differences among
guidance though and a bit far out to see any severe potential.

&&

.AVIATION /12Z MONDAY THROUGH FRIDAY/...
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The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY and surrounding areas.

Monday...VFR conditions are expected. Winds will increase out of the
northwest to 15-20 knots, with gusts 25-30 knots. High confidence.

Monday night...VFR conditions expected. Gusty northwest winds around
20 knots early in the evening, then northwest 5-10 knots.

Outlook...

Tuesday through Wednesday morning...VFR. No significant weather.

Wednesday afternoon through Wednesday Night...Restrictions likely
(60-80%) with SHRA/TSRA as a cold front comes through.

Thursday...Some restrictions possible for the first half of the day
possible (30%), mainly at KACY/KMIV. Otherwise, primarily VFR.

Thursday Night through Friday...VFR. No significant weather.
-- End Changed Discussion --

&&

.MARINE...
Small Craft Advisory will continue into Monday evening and Monday
night. A brief lull in winds early this morning will drop gusts
below SCA criteria, but ramp right back up behind the cold front
with gusty NW winds 25+ kts developing in the afternoon. Seas 4-6 ft
this morning will gradually fall to 3-5 ft this afternoon then
finally drop below 5 ft tonight.

Outlook...

Rip Currents...

Tuesday through Tuesday Night...No marine headlines expected. Fair
weather.

Wednesday through Wednesday Night...SCA conditions possible (30-40%)
as seas near 5 feet and southerly wind gusts get near 25 kt.

Thursday through Friday...No marine headlines expected.

Monday...West-northwest winds around 10-15 mph with gusts up to
20 mph and breaking waves around 2 to 3 feet. Although wind
direction will be directed offshore, wave periods are expected
to increase to around 7 to 8 seconds. For this reason, have
maintained a MODERATE Risk for the development of dangerous rip
currents for both NJ/DE beaches.

Tuesday...Northwest winds will back to southerly as the day
goes on around 10 mph. Breaking waves around 1 to 2 feet. With
winds mainly directed offshore or parallel to the coast and
much lower wave heights, have opted to go with a LOW Risk of rip
currents for all beaches.

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

&&

.CLIMATE...
With this stretch of heat, our climate sites set or tied 20
record high maximum temperatures or record high minimum
temperatures. The stretch of heat is over with the passage of
this cold front.

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...None.
NJ...None.
DE...None.
MD...None.
MARINE...Small Craft Advisory until 8 PM EDT this evening for ANZ430-
     431.
     Small Craft Advisory until 2 AM EDT Tuesday for ANZ450>452.
     Small Craft Advisory until 11 PM EDT this evening for
     ANZ453>455.

&&

$$

SYNOPSIS...Hoeflich
NEAR TERM...MJL
SHORT TERM...Hoeflich
LONG TERM...Hoeflich
AVIATION...Hoeflich/MJL
MARINE...Hoeflich/MJL
CLIMATE...