433
FXUS61 KPHI 051744
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
144 PM EDT Sun May 5 2024

.SYNOPSIS...
An east to southeasterly flow off the Atlantic ocean will result
in cloudy weather through Monday morning with areas of light
rain and drizzle. A cold front will work its way through the
region late Monday and Monday night. This boundary will become
stationary over the area through the mid- week period. A series
of disturbances will track along this boundary through the
middle of the week. A stronger area of low pressure moves
through the region on Thursday, followed by a cold front on
Friday.

&&

.NEAR TERM /THROUGH MONDAY/...
Weak warm advection overruning a very moist and cool marine
layer will keep low clouds and light rain or drizzle for most
locations through Monday morning. As a shortwave moves over the
region this afternoon, showers along and west of the Delaware
Valley will spread eastward into coastal areas.

The bulk of the rain moves out early this evening, but another
weak trough approaching tonight will reinforce lift and
generate additional scattered showers. Some of the model
soundings show some elevated instability, so can`t rule out some
lightning strikes late tonight, mainly within Delmarva and the
southern half of New Jersey. Some patchy fog is possible with a
moist boundary layer, greatest chance mainly north and west of
the Philadelphia metro. It will be a mild night, with lows in
the mid to upper 50s/low 60s.

Winds become southerly Monday morning ahead of a cold front that
will usher an increasingly humid airmass into the region with
surface dewpoints rising into the 60s. Any fog in the morning will
lift and dissipate by midday. The cold front passes through the
region Monday afternoon and Monday evening. Some shortwave
energy passing through the region will help kick off widely
scattered afternoon showers and thunderstorms, mainly across
the southern portions of the forecast area.

&&

.SHORT TERM /MONDAY NIGHT THROUGH TUESDAY NIGHT/...
The front becomes stationary south of the region Monday night
through Tuesday night. High pressure builds north of the region,
and an onshore flow develops, bringing somewhat cooler and
drier air down into the region. Another disturbance approaches
from the west late Tuesday and Tuesday night, touching off
another round of scattered showers and thunderstorms over the
region.

&&

.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
A prolonged period of unsettled weather on tap for the latter
part of the new week. A series of frontal boundaries and weak
low pressure systems will pass through the region during this
time. The first system is an area of low pressure that will pass
north of New Jersey Wednesday morning, and this will drag a
cold front through the region late in the day and at night. Some
rain is possible in the morning, and then another round of
showers and mostly isolated thunderstorms will affect the area
Wednesday afternoon and Wednesday evening.

The next area of low pressure will organize and develop over
the Midwest, and a warm front will develop out ahead of this
system and lift towards the local area late Wednesday
night/early Thursday morning. This will touch off some more
showers and isolated thunderstorms during this time. A secondary
low will form over the Mid-Atlantic ahead of the primary low,
and this low works its way across the region Thursday afternoon
and Thursday night. More widespread showers and scattered
thunderstorms will affect the area during this time.

The primary low passes north of the region on Friday with yet
another round of showers as a cold front passes through the
region.

Temperatures during the period will start out warm with highs
in the 80s on Wednesday,and then temperatures will trend closer
to normal on Thursday and Friday.

&&

.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY and surrounding areas.

Rest of today...Ceilings at or below 1Kft this afternoon with
ceilings 3-4Kft across southern Delaware and southeastern New
Jersey. Highest concentration of showers should move through the
Lehigh Valley and Delaware Valley.

Tonight...Low clouds and areas of fog. South to southeast wind
around 5 kt.

Monday...Cloud deck at or below 1Kft in the morning with areas
of fog. Ceilings rise to 1-2Kft by midday. winds become
southwesterly around 10 knots.

Outlook...

Monday night through Friday...No significant weather expected
Monday through Thursday morning. Widespread showers and
thunderstorms Thursday afternoon.

&&

.MARINE...
No marine headlines expected through Monday as seas will be 2
to 4 feet with winds from the east to southeast at 10 to 20 kt.
Periods of showers expected, with a 15-20% chance of
thunderstorms early Monday morning.

Outlook...

Monday night through Friday...A prolonged period of sub-SCA
conditions. VSBY restrictions in fog throughout the week,
especially at night. Best chances for widespread showers on
Thursday afternoon.

&&

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

&&

$$

SYNOPSIS...Franklin/MPS
NEAR TERM...Franklin/Hoeflich
SHORT TERM...MPS
LONG TERM...MPS
AVIATION...Franklin/Hoeflich/MPS
MARINE...Franklin/Hoeflich/MPS