Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

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000
FXUS61 KPHI 260440
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
1240 AM EDT TUE JUL 26 2016

.SYNOPSIS...
A cold front will approach from the west and move through the
region early Tuesday morning, before stalling near or just to the
south of our area. This front will gradually lift north by the end
of the week with areas of low pressure developing along this
boundary.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
Lingering showers were passing off the New Jersey coast from
about Long Beach Island southward around 1230 AM. Meanwhile, a
complex of thunderstorms was moving across the middle Delmarva.
The thunderstorms were accompanied by downpours along with
frequent cloud to ground lightning and localized wind gusts
around 35 MPH. The thunderstorms should be to the southeast of
Delaware by 300 AM.

The sky should remain mostly clear over our northern counties
during the balance of the night and it will be partly cloudy over
the south. We are anticipating areas of fog to develop, especially
where heavy rain has occurred.

The wind is forecast to be light and variable. Low temperatures
will favor the 60s up north and the 70s elsewhere.

&&

.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM TODAY/...
The cold front is expected to slow down as it moves southward
through the Delmarva early Tuesday morning. There is still
uncertainty regarding how quickly the front pushes southward.
Fronts tend to get hung up in the Delmarva this time of year and
in this pattern with zonal steering flow aloft. Added a chance for
showers and storms during the afternoon hours across the southern
half of DE and adjacent eastern MD with the front likely nearby.

Unfortunately, we won`t get much of a break from the heat
tomorrow as post-frontal CAA progged to be minimal. Forecast highs
are in the low to mid 90s across most of the area (except cooler
in the higher terrain of northeast PA/northwest NJ and along the
coast). However, it will be noticeably less humid across eastern
PA and central/northern NJ with dewpoints in the upper 50s and
lower 60s. Farther south, where the front gets hung up, dewpoints
will still be in the upper 60s and lower 70s. Afternoon heat
indices should peak near 100F in the Delmarva.

&&

.LONG TERM /TONIGHT THROUGH MONDAY/...
The medium range models are in good agreement keeping high pwat
air just to our south as a sfc boundary stalls in the southern
portion of the forecast area. Higher humidity values and a slight
chance for storms will continue near the Delmarva. Heat index
values in the mid 90s are still expected from Philadelphia
southward.

In response to an approaching shortwave, heights build on
Thursday and 1000-850mb thicknesses increase resulting in temps
climbing a couple of degrees warmer compared to Wednesday, with
heat index values in the mid to upper 90s. As higher pwat air
returns...and shortwave energy moves through the region...widely
scattered to scattered storms also return Thursday.

The ECMWF/GFS/Canadian models are coming into better agreement
developing a broad upper trof over the eastern U.S. into the
weekend...bringing temperatures down closer to normal values for
late July/early August. With pwat values still 1.5-2.0" through
Monday, and weak shortwaves moving through the upper trof axis,
daily afternoon and evening showers and storms will be possible
through the remainder of the long term period.

&&

.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY and surrounding areas.

Overnight...Behind the evening showers and storms, winds will
shift more to the west, slightly northwest, but remain under 10
knots. Patchy fog will develop in the more prone areas as winds go
light and skies largely clear.

Tuesday...Patchy fog early, clearing by around 15Z. Then VFR
conditions expected for the remainder of the day. Westerly winds
around 10 to 12 knots through the afternoon.

Outlook...
Tuesday night through Friday...Mainly VFR conditions expected.
Scattered showers and thunderstorms Thursday and Friday, with
MVFR/IFR conditions possible at times.

&&

.MARINE...
Winds and seas will be just below small craft advisory criteria
through tomorrow. Seas will increase from 2 to 3 feet to 4 feet
in our coastal waters.

Outlook...
Tuesday night through Friday...Sub-advisory conditions are
expected to continue on the area waters through much of the week.
Expect higher winds and waves in and near scattered showers and
thunderstorms that become more likely at the end of the week.

Rip Currents...A moderate risk for rip currents continues through
thE NIGHT. Tuesday through the most of the week: with the Atlantic
Basin continuing quiet tropically, unless we get a strong onshore
flow...RC risk this coming week should be generally low. Tstms and
pockets of chilly upwelling water may the greater concerns. There
is some sign of colder upwelling along the coasts this evening.

&&

.CLIMATE...
The last time the temperature reached or exceeded 98F at PHL was
three years ago on July 18, 2013. The last 100-degree day at PHL
occurred four years ago on July 18, 2012.

Record high temperatures for Today through Thursday are below.

Site     26th       27th       28th
----     ----       ----       ----

PHL...   101-1892   101-1940   100-1941

ABE...    98-1940    98-1955    97-1949

ACY...    96-2011    99-2005    98-1999

ILG...    99-1894   100-1894   101-1894

TTN...    99-1892   100-1894   101-1894

GED...    97-2012    98-2005    99-1949

RDG...    99-1940    98-1955    99-1941

MPO...    89-1949    91-1955    93-1949

&&

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

&&

$$

Synopsis...99
Near Term...Iovino
Short Term...Klein
Long Term...99
Aviation...Meola
Marine...Meola
Climate...Staff



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