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Area forecast discussion 
National Weather Service Mount Holly New Jersey
645 PM EDT Friday Jul 29 2016

Synopsis...
scattered showers and thunderstorms with locally heavy rainfall
will re-develop Saturday afternoon and linger into Monday with low
pressure and a frontal boundary hung up across the mid Atlantic
states. High pressure will then bring mainly dry and less humid
weather for the remainder of the next work week.

&&

Near term /until 6 am Saturday morning/...
630 PM estf: fcstg band of heavy showers moving south into northern
NJ, which may remain alive until dissipating around 9 PM.

Then dry overnight.

Winds will be continuing to diminish. This, combined with the
recent heavy rainfall across portions of the region means we could
see patchy fog especially across the axis of heaviest precip in
northern Delmarva, The Pine Barrens and the northwest tip of New Jersey.

&&

Short term /6 am Saturday morning through 6 PM Saturday/...
the upper level trough becomes more defined as it moves closer to
the region. As a result, should see an area of precipitation move
into the region (exact timing is uncertain by the higher chances
look to be in the afternoon). As far as hazards, the primary hazard
appears to be heavy rain. Precipitable water values are well above
normal, and storm motions look to be quite slow (<15 kts) as the
flow is weak. However, with limited focus for surface convergence
(at least over our immediate area), not confident that there will be
a widespread flooding threat. Thus, not planning to issue a Flash
Flood Watch at this time.

&&

Long term /Saturday night through Friday/...
highlights...

* scattered showers and thunderstorms Saturday night/Sunday with the
potential for heavy rainfall and a very localized flood threat

* scattered showers/thunderstorms linger Monday, otherwise much of
the next work week will be dry and less humid

Details...

Saturday night and Sunday...

A couple of additional shortwaves will move across our region along
with a frontal boundary in the vicinity. The result will be periods
of scattered showers and thunderstorms Saturday night into Sunday.
Specific timing is uncertain at this point, but pwats of 2+ inches
will bring the potential for locally heavy rainfall. While any
flood threat looks very localized, weak low level wind fields may
result in slow movement and back building of any thunderstorms,
so that will need to be watched. Weak wind fields will also result
in a low overall risk for severe weather, but a few strong storms
can not be ruled out.

Monday...

Guidance has trended a bit slower over the past 24 hours. Frontal
boundary will still be across our region along with another piece of
shortwave energy moving in on Monday. The result will be the
continued chance for scattered showers and thunderstorms.

Tuesday through Friday...

Large high pressure will be building across the mid Atlantic states.
While we can not rule out a few lingering showers Tuesday, mainly
dry and less humid weather is expected through Friday. High temps
will mainly be in the 80s for much of the next work week.

&&

Aviation /00z Saturday through Wednesday/...
the following discussion is for kphl, kpne, kttn, kabe, krdg,
kilg, kmiv, kacy and surrounding areas.

Tonight...VFR with sct clouds aoa 6000 ft. Showers should dissipate
as they approach krdg/kabe this evening. Light wind becoming calm
with a chance of patchy fog NW New Jersey and in the seabreezed areas of
coastal New Jersey and coastal Delaware.

Saturday...cirrus ceilings lower to sct-bkn aoa 3500 ft during
the afternoon with showers and isolated tstms spreading newd.
Showers could begin to move into the western taf sites (kabe,
krdg) after 15z and Delaware valley taf sites (kphl, kpne, kilg,
and kttn) after 18z. East or southeast wind.

Outlook...

Saturday night through Monday...moderate to high confidence.
VFR dominates but periods of lower conditions expected in
scattered showers and thunderstorms.

Tuesday and Wednesday...moderate to high confidence in mainly VFR
conditions.

&&

Marine...
winds and seas should remain below Small Craft Advisory criteria tonight and
tomorrow.

Outlook...Saturday night through Wednesday...a wave of low pressure
may result in a brief period of marginal Small Craft Advisory seas
across our northern waters Sunday afternoon/early evening.
Otherwise, weak pressure gradient should keep winds/seas mainly
below Small Craft Advisory thresholds through Wednesday. Main
concern for mariners will be the threat of scattered thunderstorms
Saturday night through Monday.

Rip currents...the probability for the development of dangerous
rip currents on Saturday is low.

&&

Climate...
phl: heading for top 8 warmest July on record. July avg temp for
phl will be about 80.9 or 81.0f, 8th warmest July in the period of
record since 1874. If its 81... would be tied for 7th.

Acy: 8.77 inches as of 5 PM ranks 6th wettest July on record with
its monthly record of 13.09 set in 1959. The por is back to 1874.

1959 13.09
1969 12.64
1958 10.92
1945 10.22
1903 10.14
2016 8.77

July normal 3.72

Still opportunity to rise in the monthly ranking, though wpc has
only about .75 for the rest of the month.

&&

Phi watches/warnings/advisories...
PA...none.
New Jersey...none.
Delaware...none.
Maryland...none.
Marine...none.

&&

$$
Synopsis...99/drag 645
near term...drag/Johnson 645
short term...Johnson
long term...99
aviation...Johnson/99 645
marine...Johnson/99 645
climate...645

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