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fxus61 kphi 200715 
afdphi

Area forecast discussion
National Weather Service Mount Holly New Jersey
315 am EDT Fri Sep 20 2019

Synopsis...
high pressure across the middle Atlantic region today will weaken
and move offshore by the end of the weekend. Low pressure will move
across Canada and cause a cold front to cross our region Monday
night. More high pressure will build in next Tuesday and remain
through the middle of next week.

&&

Near term /until 6 PM this evening/...
the mid-level ridge over the eastern U.S. Will sharpen today. As
this occurs, surface high pressure across the northern mid-Atlantic
will settle across the Carolinas.

Vertical profiles show little moisture today. The exception is right
at the surface and between h5-h3. As a result, we could see a bit of
fog right at sunrise and some high cirrus as we move through the
day.

So, all-in-all, another quiet day.

Afternoon high temperatures should top out about 5 degrees warmer
than yesterday. Most locations will make it into the mid to upper
70s. There will be very little change in dewpoints compared to
yesterday. Winds will be less than 10 mph from the west.

A comfortable day ahead.

&&

Short term /6 PM this evening through 6 am Saturday/...
very little change expected in the overall pattern across the
eastern U.S. Tonight. The mid-level ridge axis shifts from the
central Great Lakes to the eastern Great Lakes. Surface high
pressure remains in place.

We will see some warm air advection. West winds will transport some
warmer air from the Ohio Valley across the mid-Atlantic. So even
though skies will be mainly clear tonight and winds will go light
once again, temperatures will be several degrees warmer compared to
what's occurring right now at this hour.

Patchy shallow fog is possible toward daybreak.

&&

Long term /Saturday through Thursday/...
Sat thru Sunday night...fair weather with some increasing clouds
Sunday night. High pressure to the south will weaken and move
offshore. A return flow of mild and somewhat more humid air will be
across the area. Highs both Sat and sun will be above normal with
readings Sunday in the mid/upper 80s. Sat night will be seasonably
chilly, but Sunday night will be mild. Some patchy fog is possible
Sun morning.

Monday/Monday night...the high pressure will have moved away and a
progressive 500 mb trough and sfc cold front will approach from the northwest.
Increasing clouds for Monday with chc pops overspreading the area
from west to east. Monday will be another very warm day with highs like
that on Sunday.

Tue/Wed/Thu...more fair weather is expected during the mid-week
period with another high pressure area building across the area.
Temperatures Tue/Wed will be close to normal but then readings will
jump back above normal for Thursday.

&&



Aviation /07z Friday through Tuesday/...
the following discussion is for kphl, kpne, kttn, kabe, krdg, kilg,
kmiv, kacy and surrounding areas.

Today...VFR. Light west-SW winds in the morning, becoming west-SW 5 to 10
kt in the afternoon.

Tonight...mainly VFR conditions expected. Patchy fog possible. Light
west-SW winds.

Outlook...
Saturday thru Sunday night...VFR expected. Increasing clouds Monday.
Patchy morning fog possible each day.

Monday and Monday night...mostly VFR. Scattered showers.

Tue...VFR expected.

&&

Marine...
today...southwest winds increasing to 10 to 15 knots. Seas at the
buoys, very early this morning, are showing 5 to 8 feet. They are
expected to diminish to 4 to 6 ft later today. But as a result of
seas remaining 5 feet or higher, a Small Craft Advisory is in place. Dominant periods
are long...about 9 to 12 seconds. But as the wind increases this
afternoon, periods will effective shorten.

Tonight...Small Craft Advisory conditions should continue for much of the night. West
winds should continue to gust in the 15 to maybe 20 kt range. Long
period swells emanating from Humberto should begin to slowly drop
off after midnight.

Outlook...
Sat/sun...sub-sca conditions expected with fair weather. Winds and
seas will slowly increase Sunday afternoon.

Sun night/Monday...Small Craft Advisory conditions expected on the ocean and sub-Small Craft Advisory
across Delaware Bay. Scattered showers Monday.

Mon night thru Tue...mostly sub-Small Craft Advisory expected. Few showers Mon
night then fair.

Rip currents... a high risk for the development of dangerous rip
currents continues through today as the long period swells and high
seas continue from Hurricane Humberto. A rip current statement
(under the coastal hazard message) is carrying the related info.

&&

Phi watches/warnings/advisories...
PA...none.
New Jersey...high rip current risk through this evening for njz014-024>026.
Delaware...high rip current risk through this evening for dez004.
Maryland...none.
Marine...Small Craft Advisory until 8 am EDT Saturday for anz450>455.

&&

$$
Synopsis...O'Hara
near term...kruzdlo

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