649
FXUS61 KPHI 242105
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
505 PM EDT Sat May 24 2025

.SYNOPSIS...
Low pressure continues to move away from the region over the next
couple days as it moves into the Canadian Maritimes while high
pressure gradually builds in from the north and west through Monday.
Low pressure tracks into the Ohio Valley while another low tracks
well to our south Tuesday and Wednesday. A cold front may then
approach from the west later Thursday.

&&

.NEAR TERM /THROUGH SUNDAY/...
The upper low across New England continues to pull away to the east.
Surface high pressure over MI/OH will build SE tonight and Sunday
while slowly weakening. Clouds continue across most areas with
breaks across Delmarva and south NJ. Scattered showers are across
the northern half of the CWA as of 2PM. These clouds and showers
will be around thru the early evening before diminishing. We`ll
continue with chance pops for the situation. Winds decrease too this
evening with gusts 20 to 25 mph at times.

Overnight, skies will be partly clouds and temperatures will be cool
for this time of year. Lows will drop into the 40s most spots. Winds
will be West to Northwest at 5 to 10 mph.

Fair weather is expected Sunday with fewer clouds than today. The
winds will also be less active with speeds mostly around 10 mph
and perhaps a few gusts of 15 to 20 mph. Temperatures will remain
cool for late May with highs only in the mid/upper 60s for the
N/W and low 70s for Delmarva and south NJ.

&&

.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY/...
High pressure gradually building south and east into the area will
dominate most of the area for Sunday night through Monday. The one
thing that will have to be watched is a weak disturbance sliding by
south of us. Most likely its precipitation will stay to our south
but we do maintain a 20 to 30 percent chance of showers over most of
our Delmarva counties for Sunday night. Expect highs Monday mostly
in the low to mid 70s except cooler over the southern Poconos and
near the shore as the relatively light winds should allow a
seabreeze to develop. Monday should also feature a partly to mostly
sunny sky.

High pressure crests over the area Monday night and then begins to
retreat slightly during Tuesday as the next system approaches. It
should remain dry though through Tuesday but with increasing mid and
high level cloudiness. Expect lows Monday night ranging from the mid
40s to mid 50s with highs Tuesday similar to Monday...generally in
the low to mid 70s except cooler near the shore and over the
southern Poconos.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
The long term period turns more unsettled once again as the eastern
CONUS comes under the influence of an upper level pattern
dominated by more "troughiness". That said, there are still some
differences in the forecast models regarding the specifics of
how this pattern evolves. But getting into a little more detail,
there will likely be an initial shot of some rain/showers
Tuesday night into Wednesday as low pressure over the midwest
starts to approach. The main differences in the models are that
the deterministic GFS has a weaker and more fragmented system
while the GEM, ECMWF, and some of the GEFS ensembles favor a
system that remains more consolidated. In either case, at least
some rain is likely but the GFS solution could result in it
being mostly dry over the area by the second half of Wednesday
following the initial shot of rain Tuesday night while the ECMWF
and GEM solutions would keep it more unsettled right through
Wednesday. Beyond this time, an approaching cold front will
bring chances for more showers and storms by later Thursday and
then a new upper level low looks to move south and east by the
end of next week into next weekend keeping at least chances for
some showers/storms around, mainly in the PM hours. So all in
all, a generally unsettled several days but it won`t be raining
this entire time. And as we get closer to midweek we`ll be able
to better refine timing as far as when the best chances for wet
weather will be.

&&

.AVIATION /21Z SATURDAY THROUGH THURSDAY/...
.Tonight... Decreasing clouds and winds around dusk. Scattered low
clouds and some high clouds overnight. Northwest to west winds decreasing
to the 5 to 10 knots range. High confid.

.Sunday... VFR. Scattered low clouds and some mid/high clouds for
Delmarva and south NJ. West to Northwest winds around 10 knots with
some gusts 15 to 20 kts after 14Z/15Z. Medium/high confid.

Outlook...

Monday and Tuesday...Prevailing VFR.

Wednesday through Thursday...periods of MVFR or lower possible with
rain showers.

&&

.MARINE...
Winds have started to diminish across the waters so we`ll drop the
SCA flag with the 4PM issuance product issuance. Winds and seas will
remain below SCA levels thru Sunday. West to Northwest winds around
10 knots with some gusts around 20 kts Sunday afternoon. A few
widely scattered showers into the evening then Fair tonight and
Sunday.

Outlook...

Sunday night through Tuesday...winds and seas are expected to stay
below Small Craft Advisory conditions.

Wednesday through Thursday...marginal Small Craft Advisory
conditions will be possible due to seas getting to around 5 feet.

Rip Currents...

For Sunday, west-northwest winds around 10-15 mph and breaking
waves of 1-2 feet with periods of 8-10 seconds. This results in
a LOW risk for the development of dangerous rip currents for all
beaches.

For Memorial Day, north winds around 5-10 mph in the morning,
becoming east-southeast in the afternoon. Breaking waves of 1-2
feet with periods of 8-10 seconds. This results in a LOW risk
for the development of dangerous rip currents for all beaches.

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

&&

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

&&

$$

SYNOPSIS...Fitzsimmons/Gorse/RCM
NEAR TERM...OHara
SHORT TERM...Fitzsimmons
LONG TERM...Fitzsimmons
AVIATION...Fitzsimmons/OHara
MARINE...DeSilva/Fitzsimmons/OHara