Area Forecast Discussion
Issued by NWS Mt. Holly, NJ

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000
FXUS61 KPHI 291217
AFDPHI

Area Forecast Discussion
National Weather Service Mount Holly NJ
817 AM EDT FRI JUL 29 2016

.SYNOPSIS...
Low pressure near the Delmarva will strengthen as it moves east
off the New Jersey coast today. Another area of low pressure will
develop near the Delmarva Saturday night and slowly drift out to
sea through Monday. Drier and less humid weather is expected by
the middle of next week as high pressure builds over the region.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
8 AM update...have cancelled the flash flood watch for locations
where the heaviest rain has moved out. The watch remains in effect
for portions of the NJ coastal plains through noon.

previous near term discussion...Surface low pressure was located
off the Delaware coast around 6:00 AM. The feature will move east
northeastward and it should pass farther off the coasts of
Delaware and southern New Jersey this morning before moving
quickly out to sea.

A band of moderate to heavy rainfall was located in the lift to
the northwest of the low. It extended from the upper Delmarva up
into southeastern Pennsylvania and New Jersey around 6:00 AM. As
the low makes its way out over the ocean, the precipitation will
pull away to our northeast and east during the late morning and
afternoon hours. The cloud cover is forecast to lift and break
gradually with some sunshine developing during the afternoon.

The wind is anticipated to favor the northeast to northwest
quadrant for today. Speeds may increase to 10 to 15 MPH on the
coastal plain and 5 to 10 MPH inland. The cloud cover and the
northerly flow should keep temperatures from rising above the 80s
this afternoon.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 AM SATURDAY/...
We should remain between weather systems for tonight with the low
moving farther out to sea. Weak areas of low pressure are forecast
to be over the Ohio River Valley and eastern Virginia and North
Carolina. High pressure is expected to be to our north.

We are anticipating a partly to mostly cloudy sky with a light
wind. A few light rain showers may begin to push into our region
from the west after midnight.

Minimum temperatures are forecast to be in the middle and upper
60s in the north and in the lower 70s in the south.

&&

.LONG TERM /SATURDAY THROUGH THURSDAY/...
Highlights...

* Scattered showers and thunderstorms with potential for locally
  heavy rainfall this weekend
* Transition to drier and less humid weather trending a bit slower
  during the early to middle part of next week

Details...

Saturday and Sunday...

A couple of additional shortwaves will move across our region
this weekend along with a frontal boundary in the vicinity. Right
now,it appears that the timing for the increased threat of showers
and thunderstorms will be from Saturday afternoon through Sunday
evening.

Plenty of moisture will linger through the weekend, so the threat
will remain for locally heavy rainfall. Cloud cover and showers
and thunderstorms will help hold temperatures in the 80s across
much of the region. But, humid conditions will persist with dew
point temperatures hovering around 70 in many locations.

Monday through Thursday...

Each model run is trending a bit slower with the eventual
transition to a drier weather pattern and the 29/00Z guidance is
no different. Will keep at least a slight chance of showers and
thunderstorms in the forecast through Tuesday. Likely will see
diurnally driven showers and thunderstorms on Monday and then
potentially another uptick on Tuesday as an upper level trough
finally pushes through to sweep the stagnant frontal boundary to
our south.

High pressure will build over the region, bringing us drier and
somewhat less humid weather. Look for high temperatures in the
lower to mid 80s and dew point temperatures in the lower to mid
60s, which will be quite a change from the week to 10 days
preceding it.

&&

.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
The following discussion is for KPHL, KPNE, KTTN, KABE, KRDG,
KILG, KMIV, KACY and surrounding areas.

An area of moderate to heavy rain will continue to move eastward
across our TAF sites early this morning. It was already east of
KRDG and KABE at 1000Z. Conditions will favor the IFR and MVFR
categories. The rain is forecast to begin moving out of our region
and to our northeast and east during the mid to late morning.
Conditions should begin to improve gradually at that time and we
are anticipating VFR conditions for the afternoon hours.

VFR conditions are forecast to continue into tonight. However,
some MVFR visibility restrictions may develop.

The wind is expected to favor the northeast to northwest quadrant
for today at speeds of 6 to 12 knots.

Outlook...
Sat through Sun...Shra/tsra will lower cigs/vsbys at times
Moderate Confidence.

Mon...Mainly VFR. Moderate Confidence.

&&

.MARINE...
Rain with embedded thunderstorms is anticipated for this morning.
The precipitation should move to our northeast and east during the
afternoon.

Low pressure was passing off the coast early this morning and it
will move out to sea. A northeast to north wind is expected for
today on the coastal waters of New Jersey and Delaware with speeds
increasing to 10 to 20 knots. Wave heights are anticipated to
build to around 3 feet on our ocean waters.

Wind speeds are expected to diminish to 10 knots or less for
tonight and the direction may go variable for a time.

Outlook...Saturday through Tuesday...
Winds come up a bit with the weak low pressure development nearly
over the waters on Sunday, otherwise expect generally a light wind
flow for much of the period. Biggest concern for mariners will be
the risk for thunderstorms this weekend.

RIP CURRENTS...The prevailing risk category for the development
of dangerous rip currents along the coasts of New Jersey and
Delaware for today is low. However, a northeast to north wind may
bring periods of moderate risk.

The probably risk for the development of dangerous rip currents
on Saturday is low

&&

.CLIMATE...
GED: a record daily rainfall of 2.80 inches occurred for the
28th.

PHL: heading for top 10 warmest July on record. July avg temp for
PHL will be about 80.9F, 8th warmest July in the period of record
since 1874.

ACY: already is at least 7th wettest July on record with its
monthly record of 13.09 set in 1959. The por is back to 1874.
Total for the month as of the 28th: 8.35".

&&

.PHI WATCHES/WARNINGS/ADVISORIES...
PA...None.
NJ...Flash Flood Watch until noon EDT today for NJZ012>015-018>027.
DE...None.
MD...None.
MARINE...None.

&&

$$
Synopsis...99
Near Term...Iovino/Johnson
Short Term...Iovino
Long Term...99
Aviation...Iovino/99
Marine...Iovino/99
Climate...



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