841
FXUS61 KPHI 130754
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
354 AM EDT Mon May 13 2024

.SYNOPSIS...
High pressure builds south of the Mid-Atlantic region through
the day today. Unsettled weather returns through the middle of
the week with a slow moving low pressure system. After brief
ridging towards the end of the week, more unsettled weather
returns for the weekend.

&&

.NEAR TERM /THROUGH TONIGHT/...
High pressure centered offshore of New Jersey is resulting in
tranquil weather conditions across the area this morning. Mostly
clear skies are found across much of the area with the exception of
eastern PA and northwest NJ where some low stratus has developed. As
winds are nearly calm and dew point depressions continue to lower,
anticipate some patchy fog to develop where skies are clear. Temps
this morning will be quite chilly in the 40s, with even some upper
30s in sheltered locations.

Fog and stratus is anticipated to dissipate by mid-late morning
giving way to mostly sunny skies this afternoon. An increase in
clouds may occur briefly across the Poconos and northern NJ late in
the day as a warm front lifts north across northern PA. Associated
shortwave energy will also be ridging along the northern periphery
of the upper ridge which may cause an isolated shower to occur in
these areas. However, the likelihood of occurrence is quite low, so
do anticipate most locales to remain dry. Regardless, a pleasant day
is expected with afternoon temps rebounding into the low to mid 70s
as the upper ridge builds overhead. Temps in the Poconos will be in
the mid 60s, with upper 50s to low 60s along the coast due to
seabreeze development.

Fair weather continues into tonight as high pressure remains
positioned offshore. Will see an overall increase in clouds late
tonight as the next system approaches, however no precipitation is
expected until Tuesday. Lows will be a bit warmer than this morning
mainly in the 50s.

&&

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
Showers return to the region Tuesday as height falls and PVA
will amplify lift across the forecast area. Moisture coming from
the Appalachians will move through the region and provide a
steady dose of showers late Tuesday afternoon through Wednesday.
Modest warm air advection pushes temps into the mid 70s to near
the upper 70s as the showers arrive. Guidance backed off a bit
from the 12z suite with precip totals with the max values on
the order of close to an inch over 36 hours right along the
coastline with around 0.5-0.75 over the I95 corridor with less
towards the western locations. CAPE seems relatively weak so
while a few rumbles of thunder may occur, its a low (<15%)
chance.

Wednesday still looks to be a wet day as the low pressure
system starts moving out of the region. Lingering showers should
continue through most of the day before drier air starts moving
into the area. However the low doesn`t move out quickly so
we`ll have the potential to see showers well into the evening.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
Heading towards the end of the week, Thursday should be a
mostly quiet day as an upper level ridge starts to build into
the region. Again there are still strong timing differences
between the EC ensembles and the GFS ensembles with respect to
the speed of the systems. The GFS and its ensembles are more
progressive and leads to a dry day on Thursday while the EC and
its ensembles are slight slower which would allow for isolated
showers to develop Thursday afternoon.

The brief break in rainfall ends heading into the weekend as
the next system starts to move into over the weekend. Guidance
still shows too much uncertainty to feel confident in details at
this point but the general consensus is that a northern stream
upper level trough will strengthen and bring showers to the
region sometime over the weekend with the most likely timing now
on Saturday.

Temps in the extended from Thursday onwards should be fairly
seasonable in the mid to upper 70s for highs and lows in the
upper 50s to near 60 each night.

&&

.AVIATION /08Z MONDAY THROUGH FRIDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY and surrounding areas...

Through 12Z...For KRDG/KABE, MVFR CIGs are expected to lower to IFR
CIGs by 09Z with periods of mist and patchy fog. For the remainder
of the terminals, VFR CIGs are expected to lower to MVFR CIGs around
09-10Z. Again, patchy fog or low stratus will be possible, but not
widespread. Winds light and variable or calm. Moderate confidence.

Today...Lingering fog and low clouds scatter out by 13-15Z, before
improving to VFR conditions for the afternoon. South-southwest winds
around 8-13 kt. High confidence.

Tonight...VFR expected. Mostly clear skies with an increase in
clouds late. South winds around 5-10 kt. High confidence.

Outlook...

Tuesday...Sub-VFR conditions move in late with occasional
showers.

Tuesday Night through Wednesday night...Sub-VFR conditions
expected with occasional showers.

Thursday/Friday...No significant weather expected.

&&

.MARINE...
No marine headlines are in effect through tonight. Fair weather.
South-southwest winds around 10-15 kt this morning will increase to
around 15-20 kt this afternoon. A few gusts into the 20-23 kt range
possible late. For tonight, south-southwest winds diminish to around
10-15 kt. Seas of 3-4 feet.

Outlook...

Tuesday through Wednesday...SCA conditions anticipated (40-50%)
as wind gusts get near 25 kt. Significant wave heights approach
7 feet Wednesday. Occasional showers.

Wednesday night and Thursday... SCA seas continuing,
diminishing Thu. Showers Wed night then mostly fair Thursday.

&&

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

&&

$$

SYNOPSIS...Deal/Franklin
NEAR TERM...Desilva
SHORT TERM...Deal
LONG TERM...Deal
AVIATION...Deal/Desilva
MARINE...Deal/Desilva