567
FXUS61 KPHI 062003
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
403 PM EDT Mon May 6 2024

.SYNOPSIS...
Overall a very unsettled pattern in place this week. A cold
front approaching from the west will work its way through the
region tonight before becoming nearly stationary south of
Delmarva. Low pressure tracks along the front late tonight
through Tuesday morning. Another area of low pressure passes
through the region on Wednesday followed by a stronger low on
Thursday. A cold front passes through on Friday. Several
disturbances are possible this upcoming weekend.

&&

.NEAR TERM /THROUGH TUESDAY/...
A cold front will slowly slide south across the forecast area
tonight. With the best Omega and RH across the southern half of the
forecast area, PoPs will be highest here for the overnight.

Showers can be expected with embedded thunderstorms. As alluded to,
most of the rain should be confined to areas south of Philadelphia,
but can`t rule out a few showers as far north as the I-78 corridor.

As for rainfall, a quarter to a half inch of rain can be anticipated
down around southern New Jersey and Delmarva.

Although there is a cold front expected tonight, fog is once again
in the forecast, and it could be dense in spots. Drier air will be
slow to move in and there is very little wind accompanying the
front.

Overnight lows will be in the lower 50s to lower 60s.

Weak low pressure will be just east of Delaware Tuesday morning.
This will keep showers and isolated thunderstorms in the forecast
through at least the daybreak hours. Showers and thunderstorms are
expected to decrease by lunchtime as low pressure moves offshore.
PoPs won`t be zero for the remainder of the day, but the most
widespread precipitation should be in the morning.

Afternoon highs will be in the 70s.

Another area of low pressure will track from the Great Lakes into
the Ohio Valley. A warm front extending out from that system will
lift towards southwest portions of the forecast area later in the
day.

&&

.SHORT TERM /TUESDAY NIGHT THROUGH THURSDAY NIGHT/...
Another area of low pressure will track from the Great Lakes into
the Ohio Valley. A warm front extending out from that system will
lift towards southwest portions of the forecast area Tuesday night.
Scattered showers and thunderstorms will develop in the evening and
then become likely for most of the region after midnight Tuesday
night and into Wednesday morning as that warm front lifts through
the region. Precipitation tapers off by midday Wednesday, and then a
warm and humid airmass will be in place. Highs top off in the mid to
upper 80s, except for the low 80s in the southern Poconos and
northern New Jersey, and in the 70s along the coasts. Surface dew
points will be in the upper 50s to low 60s in the afternoon.


Low pressure approaches from the west Wednesday night, and scattered
showers and isolated thunderstorms will move into portions of
southeast Pennsylvania and Delmarva late Wednesday night. As the
main surface low tracks towards western New York and
Pennsylvania, a secondary low will develop out ahead of this
primary low, resulting in more widespread showers with
scattered thunderstorms moving into the region Thursday
afternoon and evening as a warm front lifts north of the region.
Global guidance has indicated some instability as the warm
front lifts north, suggesting the potential for some strong to
severe thunderstorms south of the warm front during the
afternoon, but exactly how far north the warm front progresses
will greatly determine the coverage of any strong to severe
storms in our forecast area. At the moment, it remains too
uncertain to mention anything more specific at this time. Even
the afternoon high temperatures will be highly variant on where
the warm front ends up, with low to mid 60s north of the front
and mid to upper 70s south. Showers and storms will taper off
Thursday night as the storm system shifts offshore.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
A cold front will push through the region Friday afternoon and
evening. Yet another round of scattered showers and isolated
thunderstorms will affect the area during that time.

Behind the cold front, surface high pressure builds east.
Several weak disturbances may touch off some afternoon showers
on Saturday and Sunday.

Highs will then be in the 60s for southeast Pennsylvania and
New Jersey and in the low to mid 70s in Delmarva on Friday.
Below normal highs expected for Saturday and Sunday, generally
in the low to mid 60s.

&&

.AVIATION /20Z MONDAY THROUGH SATURDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY and surrounding areas.

Tonight...MVFR/VFR conditions are likely to drop to IFR around
midnight or so. Fog is possible once again...and it may be dense.
Winds will be light and variable. Higher confidence the terminals
see IFR, but lower confidence on how thick or widespread the fog
will become.

Tuesday...After some IFR in the morning, visibilities and ceilings
are expected to rise into the VFR category. Light E to NE winds.

Outlook...

Tuesday night through Saturday...Sub-VFR conditions at night in
fog and stratus, while VFR conditions overall during the day.
Chances for SHRA/TSRA throughout the period with sub-VFR
conditions. More widespread SHRA with scattered TSRA Thursday
afternoon and evening.

&&

.MARINE...
Tonight...Sub-SCA conditions expected. Mainly a light south wind
with seas 2 to 3 feet. Areas of fog...possibly dense.

Tuesday...Sub-SCA conditions expected. Light south winds becoming NE
5 to 10 kts. Seas 2 to 4 feet. Areas of morning fog...possibly
dense.

Outlook...

Tuesday night through Saturday...Overall, sub-SCA conditions
through the period. Scattered showers and thunderstorms will
result in locally higher wind gusts and seas, with biggest
impacts coming on Thursday afternoon and evening.

&&

.TIDES/COASTAL FLOODING...
Astronomical tides will be elevated this week with a new moon
on Tuesday. Minor tidal flooding and spotty moderate tidal
flooding is likely during the high tide cycles starting Tuesday
evening and continuing into at least Thursday. Coastal Flood
Advisories will be needed.

&&

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

&&

$$

SYNOPSIS...MJL
NEAR TERM...Kruzdlo
SHORT TERM...MJL/MPS
LONG TERM...MJL/MPS
AVIATION...Kruzdlo/MJL
MARINE...Kruzdlo/MJL
TIDES/COASTAL FLOODING...