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Area forecast discussion 
National Weather Service Mount Holly New Jersey
1206 am EDT Sat Aug 30 2014

high pressure will continue to move northeast of our area
overnight. A warm front will lift north of our region late
Saturday, then this front will become nearly stationary near the
Canadian border during Sunday through Tuesday. A weak cold front
is then projected to move through our region late Tuesday into
early Wednesday, followed by high pressure returning later in the


Near term /until 6 am Saturday morning/...
high pressure at the surface will continue to shift to our
northeast overnight, allowing for a weak return flow to occur.
Meanwhile, an upper-level ridge will crest over the region
overnight. There will be some high level clouds at times cresting
this ridge, while some deeper moisture is located to our southwest.
The light winds and little in the way of clouds so far has
resulted in decent radiational cooling, especially areas where the
dew points are lower so far. The cooling of the boundary layer
combined with light winds may result in patchy ground fog.

The hourly temperatures were adjusted based on the latest
observations, then the lamp/lav guidance was blended in to help
assist with trends.


Short term /6 am Saturday morning through 6 PM Saturday/...
winds will shift to southerly and increase by at least middle morning.
This warm air advection will result in maximum temperatures a few degrees
higher than today, even in spite of any patchy fog that may linger
into the middle morning hours.

Southerly gusts 15 miles per hour during the afternoon.


Long term /Saturday night through Friday/...
hemispheric model analysis shows southeast U.S. Ridging with weak
troughing north of the Great Lakes and middle-west at the start of the
long term. Better troughing across the western U.S. Moves
eastward eventually carving into the top of the Southeast Ridge by
early next week. The prevailing southwest flow aloft decreases,
ultimately becoming more zonal, as the northern stream of the jet
moves to the north of our region late in the period.

Sunday - Tuesday...slow sagging boundary to the northwest of the region
slows even further and more than likely becomes pseudo-stationary
with strong ridging to our southeast. Middle and upper level flow,
being southwesterly, keep this boundary draped just to our northwest
as warm and moist Gomex air is pumped into the region. Multiple
middle-levels waves, with weak surface troughs, traverse the region
each day providing chances of showers and thunderstorms. The best
chances for convection continues to hone in on the Sunday night into
Monday timeframe as the strongest of the middle-level waves moves
through. Afterwards, higher than normal precipitable water airmass, possibly
exceeding 2 inches, and ample instability each afternoon should
allow for diurnally driven convection. Temperatures and
unfortunately the dewpoints will be on the increase this timeframe
making conditions feel truly like an early August day, in early

Wednesday...low pressure system well to the north of the region
sends a somewhat stronger cold front towards our area. Ridging to
our south should prevent a quick passage, but none-the-less we
currently expect the front to clear or become washed out later in
the day. Still have some low-end chances, mostly north, with this
front though it continues to lose steam running into the building
ridge to our south. We should be drying out north to south by the
afternoon hours with lowering of the dewpoints...temperatures should
still be in the upper-80s.

Thursday - Friday...high pressure continues to build back into our
region with zonal flow aloft. There does not look to be much in the
way of middle-level forcing from any of the passing shortwaves, most of
the energy stays well to our north...we should be dry both days.
Temperatures will venture back down into the normal range with
continued dewpoint lowering.


Aviation /04z Saturday through Wednesday/...
the following discussion is for kphl, kpne, kttn, kabe, krdg, kilg,
kmiv, kacy and surrounding areas.

Overnight...VFR overall. Localized ground fog may develop toward
daybreak, however confidence is on the low side. Light mainly
southeast winds.

Saturday...localized early morning fog possible, otherwise VFR with
scattered to broken bases developing around 5000 feet. Southerly
winds increasing to around 10 knots.

Saturday night...generally VFR. However, an increase in moisture
may result in patchy stratus and/or fog late. South-southwest
winds 5 knots or less.

Sunday...VFR. Scattered showers and thunderstorms north and west of
phl. MDT confidence.

Monday - Wednesday...VFR. Scattered showers and thunderstorms possible
everywhere. Low to MDT confidence on precipitation coverage.


wave heights should remain 2 to 4 feet, and winds less than 20kt,
thus conditions should remain below Small Craft Advisory criteria.
Patchy fog may develop Saturday morning on the Delaware Bay,
especially the Upper Bay, but should dissipate by late morning as
winds increase.

Sunday - Wednesday...sub-sca conditions expected across our waters
with high pressure offshore. Cold front will approach Monday and
Tuesday eventually crossing on Wednesday. Winds will back towards the
southwest on Sunday and remain that way through Tuesday. Seas will
increase but remain below Small Craft Advisory at this time.


Phi watches/warnings/advisories...
New Jersey...none.


near term...gorse
short term...drag/Johnson
long term...Heavener

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