708
FXUS61 KPHI 221448
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
948 AM EST Fri Nov 22 2024

.SYNOPSIS...
Low pressure strengthening off the New Jersey coast will
retrograde north and west today as it gets captured by an upper
level low. The low will then gradually move away through the
weekend. Weak high pressure briefly arrives for later Sunday and
Monday, followed by a cold front Monday night into Tuesday. A
low pressure system may affect the area around the Thanksgiving
Day timeframe.

&&

.NEAR TERM /THROUGH SATURDAY/...
945 AM...As of mid morning, low pressure was centered north of
the area over eastern NY state. The system is becoming
"vertically stacked" as it has become nearly co-located with the
associated large upper level low. Moisture continues to pinwheel
around the system with snow still ongoing over higher terrain
areas of the southern Poconos as well as NW NJ. Upwards of a
foot of snow has fallen around Highland Lakes. Farther south,
we`ve seen some snow start to mix in with the rain showers even
as far south as the I-95 corridor. Expect the low to linger in
our vicinity through today with continuing periods of snow in
higher elevations (over 1000 feet) north of the I-78 corridor
where another 1 to 3 inches could fall. For lower elevations
areas, any snow accumulation during the day today should be
mainly under an inch in the north with no accumulation expected
in the I-95 corridor despite some snow mixing in with rain
showers at times. South of the I-95 corridor towards the coast,
we`ve actually had some clearing and sunshine this morning but
clouds will fill back in here by this afternoon with showers
returning as precip rotates south and southeastward. So in
summary, a gray, chilly, breezy, and unsettled day. Temperatures
won`t rise too much from morning values so should generally
hover in the low to mid 30s over the southern Poconos and NW NJ
with upper 30s to low 40s farther south.

System finally heads eastward away from us this evening with
dwindling POPs. Any remaining rain/snow mix should end overnight
with little if any additional accumulations. Winds will stay
elevated and it will remain relatively cloudy, so have lows
mostly above freezing except in the Poconos and NW NJ.

Moderation takes hold with some breaks of sun for Saturday as
the system continues moving away. However, the gusty northwest
wind will continue. Highs will rebound around 10 degrees from
today, though again, with the gusty wind it will feel cooler.

&&

.SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY NIGHT/...
Overall, the short term forecast looks to be dry as the closed
upper low and surface low continue to depart and strengthen
offshore. However, the increasing strength of the offshore low will
place us on the fringe of a tight pressure gradient with high
pressure settling to our southwest. Winds will be out of the
west to northwest around 10-15 mph with gusts up to 20-25 mph
Saturday night and 20-30 mph on Sunday. Lows Saturday night
will be mainly in the upper 30s to low 40s. High temperatures
on Sunday are forecast to be in the low to mid 50s for most
locations.

As the low continues to move further away Sunday night, a weak
ridge with the aforementioned high pressure begin to build into
the region. This will help relax the pressure gradient and
Sunday night will be less breezy as a result. Dry conditions
continue with lows in the 30s.

&&

.LONG TERM /MONDAY THROUGH THURSDAY/...
THe brief period of ridging continues Monday bringing dry and
tranquil weather. Highs remain forecast to be mainly in the 50s
except for some low 60s over our southern most zones in
Delmarva and South Jersey and some 40s over the southern
Poconos.

The next system will affect the area Monday night into Tuesday
as an upper level trough and associated surface low move
eastward through Ontario into Quebec. This will drag a cold
front through the area with some showers mainly for the Monday
night into early Tuesday time frame. This system will be
relatively moisture starved so not expecting large precip
amounts. Tuesday will still be relatively mild with high
temperatures similar to Monday but will be followed by colder
but dry weather for Wednesday as high pressure briefly returns.
Expect highs Wednesday mainly in the 40s to around 50 except 30s
in the Poconos.

As we turn our attention to the end of next week, most of our
available model guidance indicates a low pressure system
developing and affecting the east coast around about
Thanksgiving Day into that night. However given that this is
still several days out, there is lots of uncertainty regarding
the system`s strength, track, and overall evolution including
timing. The track will help determine precip type (rain, snow,
or a mix) but it`s worth mentioning this looks like a setup
where there won`t be a strong, cold antecedent high. Therefore,
currently not looking like the best setup for a major snowstorm
in the urban corridor.

&&

.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY and surrounding areas.

Today...MVFR to IFR conditions overspread region from NW to SE
thru the day, first at KRDG/KABE, then I-95 terminals, then
finally KMIV/KACY toward sunset. Rain will be most common but
terminals north of KPHL may see snow, with minimal if any
accumulation. W to SW winds generally 10 to 15 kt with 20 to 25
kt gusts. Low confidence overall.

Tonight...IFR with rain/snow ending but low clouds and mist
lingering much of the night. Winds remaining W to SW 10 kts or
so. Low confidence.

Saturday...Breaking to VFR early and remaining VFR thru the day.
Wind remaining gusty from the W to NW 10-15 kts with gust to 25
kts. Moderate confidence.

Outlook...

Saturday night through Tuesday...VFR with no significant weather
through the day Monday. Some showers and associated restrictions
will be possible for a time Monday night into early Tuesday.

&&

.MARINE...
Conditions will remain at Small Craft Advisory criteria through
Saturday, with a few periods of winds gusting to around gale
force across the ocean waters, so have Gale Warnings for ocean
waters thru most of the period. Exception is the far northern NJ
ocean waters, where winds may drop off solidly to SCA tonight,
so allow Gale to drop then, but may be needed there again on
Saturday. For the Bay, winds ramp up later today thru tonight,
so have SCA transition to Gale midday and continue thru tonight.
Winds mainly west 20-25 kts with gusts 30-35 kts.

Outlook...

Saturday night through Sunday...Small Craft Advisory criteria
conditions expected. West to northwest winds 20-25 kts with gusts up
to 30 kts and seas 3-6 feet. Gale force wind gusts may linger into
the first half of Saturday night, most likely south of Great Egg
Inlet.

Sunday night through Monday...The conditions are anticipated to be
below Small Craft Advisory criteria.

Tuesday...Small Craft Advisory conditions may develop behind a cold
front.

&&

.CLIMATE...
Driest autumn (Sep-Nov) on record, and any 3-calendar month
period on record, plus current status:

                   9/1-11/21   Driest          Driest 3         Year/
Site              2024 precip  Autumn Year  Calendar months    months
Allentown (ABE)       2.60      3.81  1922      3.58        Oct-Dec 1928
A.C. Airport (ACY)    2.17      3.34  2001      2.35        Oct-Dec 1946
A.C. Marina (55N)     1.58      2.89  1941      2.52        Aug-Oct 1895
Georgetown (GED)      1.17      2.67  2001      2.20        Aug-Oct 2024
Mount Pocono (MPO)    4.25      4.21  1931      3.36        Oct-Dec 1928
Philadelphia (PHL)    1.98      2.37  1922      2.37        Sep-Nov 1922
Reading (RDG)         2.20      2.89  1922      2.89        Sep-Nov 1922
Trenton (TTN)         1.86      3.18  1922      2.66        Jun-Aug 1966
Wilmington (ILG)      1.61      3.17  1922      3.17        Sep-Nov 1922

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...Winter Weather Advisory until 4 PM EST this afternoon for
     PAZ062.
     Winter Storm Warning until 4 PM EST this afternoon for PAZ054-
     055.
NJ...Winter Weather Advisory until 4 PM EST this afternoon for
     NJZ001-007-008.
DE...None.
MD...None.
MARINE...Small Craft Advisory until noon EST today for ANZ430-431.
     Gale Warning until 6 AM EST Saturday for ANZ430-431.
     Gale Warning until 6 PM EST this evening for ANZ450.
     Gale Warning until 6 PM EST Saturday for ANZ451>455.

&&

$$

SYNOPSIS...Fitzsimmons/RCM
NEAR TERM...Fitzsimmons/RCM
SHORT TERM...AKL
LONG TERM...AKL/Fitzsimmons
AVIATION...AKL/Fitzsimmons/RCM
MARINE...AKL/RCM
CLIMATE...