Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

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FXUS61 KPHI 261340

Area Forecast Discussion
National Weather Service Mount Holly NJ
940 AM EDT FRI AUG 26 2016

A weak cold front will move across the area today and push to our
south tonight. High pressure builds to our north Saturday, then
offshore later Sunday. An area of low pressure is expected to pass
to our north Monday, bringing a front across the area later on
Monday that will slowly sag southward through Tuesday. Another
cold front is forecast to move across the area around Wednesday.


Earlier showers have dissipated/moved out of the region. There is
another area of light showers to our north, but expect this to
stay north of our region through the day. So have removed mention
of precip for the remainder of the day. Otherwise, few changes
with the 930 AM update.

An upper-level ridge still centered to our south will become the
main weather feature today. This ridge is forecast to actually build
a bit northward into our area by late afternoon. This will keep the
stronger flow from the Midwest to the Great Lakes then to New
England. At the surface, a weakening cold front will continue to
settle south and eastward across our area through midday. This
boundary may then end up dissipating during the afternoon as it is
mostly just a dew point boundary. Given the building ridge, there
is a very small window of opportunity for a shower or thunderstorm
mainly through midday. There will be more of a cap across the
southern areas due to the building ridge and then some drying
occurs from northwest to southeast during the course of the day
across much of the region. This coupled with a lack of defined
forcing is not good for convective chances.

Some convective cloud debris is expected to move across at least
parts of the region this morning, however some increase in
subsidence especially this afternoon along with some drying should
allow for less cloud cover through the day across much of the area.
It will be hot however for most areas as the boundary layer flow
turns to the west and northwest for areas behind the weakening
cold front. The heat indices will be driven by how much the dew
points lower, however a humid day overall is expected with the
highest heat indices anticipated from about the Philadelphia metro
on south and east. It still appears that the heat indices fall
short of advisory criteria.


As the upper-level ridge continues to build across our region
tonight, surface high pressure near the Great Lakes will slide
eastward. This will allow for a more northeasterly low-level flow,
although most places should have the winds decouple during the
evening. While some high level clouds may drift across from time to
time, overall a mostly clear sky is anticipated. It will be
mild/warm, however the dew points should actually drop some allowing
for a bit more radiational cooling. This is especially the case
across the northern areas where dew points are forecast to be the


The frontal boundary will continue to push to our south Saturday and
stall or wash out south of the area over the weekend while high
pressure builds to our north. This high will keep dry weather in
place across the area through the weekend. Temperatures will remain
warm over the weekend, but humidity levels will be much lower with
dewpoints only in the 60s.

The high pressure will build offshore of New England Sunday night
into Monday, and a cold front will move into the area Monday. The
front is expected to slowly move south of the area into Tuesday.
Several vorticity impulses should move across the area Monday into
Tuesday, which could help lead to isolated/scattered showers or

Another frontal boundary is forecast to move across the area
Wednesday, then push south of the area into Thursday. There could
continue to be some isolated/scattered showers or thunderstorms
Wednesday or Thursday, but the chances remain small.

Temperatures through next week will continue to be several degrees
above normal, but not as warm and humid as today.


The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG, KILG,
KMIV, KACY and surrounding areas.

Today...VFR conditions are expected. Earlier low clouds have moved
out of the region, and while there may be a few transient mid
level decks through the day, expect VFR conditions to continue. A
weak cold front settles across the area, therefore most terminals
will have a wind shift to the northwest with an increase to around
10 knots. ACY should take the longest to have a wind shift to the
west. A few showers will move across the region mainly early this

Tonight...VFR. Northwest winds diminish early, then become northeast
or locally light and variable.

Saturday through Sunday night...VFR conditions expected.

Monday-Tuesday...Generally VFR expected. A chance of isolated
showers or thunderstorms.


A weakening cold front arrives during the course of the day,
however the wind shift to the northwest looks to hold off mostly
until tonight. If a lingering pre-frontal trough however moves
through, then a wind shift to westerly would occur sooner. The
southwesterly flow has diminished some across much of the waters
early this morning, and while some uptick may occur for a time we
are expecting the conditions to remain below Small Craft Advisory
criteria. Once the wind shift to the northwest occurs this
evening, a turn more to the north and northeast is expected
overnight as high pressure builds from the Great Lakes to New

Saturday through Tuesday...Sub-Small Craft Advisory conditions
expected to continue across the waters.

For today...The risk for the formation of dangerous rip currents
is low as the winds look light enough, and there should be a wind
shift to more westerly by late day as a weak cold front settles

For the weekend into early next week...With increasing long
period swells (10-15 seconds), we will have an enhanced rip
current risk. Monday and Tuesday could have the highest risk.




Near Term...Gorse/Johnson
Short Term...Gorse
Long Term...Robertson
Marine...Gorse/Robertson is the U.S. government's official web portal to all federal, state and local government web resources and services.