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Area forecast discussion 
National Weather Service New York New York
647 am EDT Monday Sep 22 2014

Synopsis...
a cold front continues east of the area today with high pressure
building in from the west. The high pressure remains in control of
the weather through the weekend.

&&

Near term /until 6 PM this evening/...
forecast is on track with just minor adjustments to reflect latest
observations.

Otherwise...the cold front has pushed east of the County Warning Area this
morning as the deep upper trough slowly pivots east through the
day. High pressure at the surface then quickly builds in from the
west today.

With the subsidence building in...skies will clear with just
scattered middle level clouds this afternoon. Cold air advection behind the cold front
coupled with a tightening pressure gradient as the high approaches
will lend to gusty winds today...20-25mph at the highest this
afternoon.

Very little change in the temperatures today with a general
mav/met/gmos blend used. With the upper trough over the area and a
cool northwest flow...highs will be below normal...middle 60s to lower 70s.

There is a high risk of rip currents today at Atlantic Ocean
facing beaches mainly due to a swell from an offshore low pressure
system.

&&

Short term /6 PM this evening through 6 PM Tuesday/...
pressure gradient slackens overnight as high pressure builds over
the area. With mostly clear skies and light winds...low temperatures will
be able to drop into the lower 40s for interior locations and
range to the lower 50s near the NYC metropolitan...quite below normal for
this time of year.

Even with the base of an upper trough to the north of the area on
Tuesday...little moisture is in place to provide for many clouds.
Expecting a mostly sunny sky and light northwest-north flow.

Mav/met/gmos blend again worked well for temperatures. Highs on Tuesday
will be near to slightly below normal.

&&

Long term /Tuesday night through Sunday/...
strong high pressure builds into the region Tuesday night and
Wednesday...eventually lifting north of the region Wednesday night
and Thursday. This high will provide the region with fair and dry
conditions through the majority of the long term period.

The 00z model guidance has started to hint at a low pressure system
developing off the southeast coast and pass south and east of Long
Island Thursday into Thursday night. For now...thinking the high
will be strong enough to keep the precipitation associated with this
low south of the region.

High pressure re-establishes itself back over the region for the end
of the week...with continued dry conditions.

Temperatures through the long term will remain near normal through
Thursday...then rise above normal for the end of the week and
weekend.

&&

Aviation /12z Monday through Friday/...
high pressure gradually builds into the region from the west
through tonight.

West-northwest winds increase and become gusty after daybreak with isolated
gusts to 30kt. Winds generally will waver between 290 and 320 mag
during the day. Winds and gusts gradually subside this
evening...becoming light northwest after midnight.

VFR today with scattered 3.5-4.5 kft cumulus this afternoon...locally broken at
western terminals. Clearing skies tonight.

New York metropolitan enhanced aviation weather support...

Detailed information...including hourly taf wind component forecasts can
be found at: http:/www.Erh.NOAA.Gov/zny/n90 (lower case)

Kjfk fcster comments: moderate confidence in winds averaging just
left of 310 mag early this morning...veer to the right of
310 mag by middle morning...then back to left of 310 mag this
afternoon ahead of trough approach.

Klga fcster comments: moderate confidence in winds averaging just
left of 310 mag early this morning...then veer to the right of
310 mag by middle morning and remain there through the afternoon.

Kewr fcster comments: moderate confidence in winds averaging just
left of 310 mag early this morning...veer to the right of
310 mag by middle morning...then back to left of 310 mag this
afternoon ahead of trough approach.

The afternoon kewr haze potential forecast is green...which implies
slant range visibility 7sm or greater outside of cloud.

Kteb fcster comments: no unscheduled amendments expected.

Khpn fcster comments: no unscheduled amendments expected.

Kisp fcster comments: no unscheduled amendments expected.

Outlook for 12z Tuesday through Thursday...
Tuesday...VFR with light winds.
Wednesday...MVFR ceilings around 3000ft possible. East-northeast winds 5-15kt.
Thursday...VFR with light NE flow.

&&

Marine...
wavewatch is currently 2-3 feet too high with both wave heights and
swell...with the swell peaking through about 12z today. Seas will
still increase through the afternoon with ocean seas reaching
6-8ft by 18z as an offshore low continues to track northeast away
from the area. Wind also increases this afternoon behind a cold
front and gusts to 25kt are expected on the ocean waters. No
changes were made to the existing Small Craft Advisory in place. Occasional gusts
to 25 knots are also possible on the other waters but confidence too
low to issue a Small Craft Advisory.

Seas decrease through the night with winds and waves falling below
Small Craft Advisory criteria by Tuesday morning. Conditions will remain below
small craft levels on Wednesday. Model guidance is showing the
possibility of a developing low pressure system developing well
south of our waters and passing south and east of Long Island
Wednesday night through Thursday night.

There is some uncertainty to the intensity and track of the low.
Guidance is indicating a strong pressure gradient between the low and
high pressure north of the region...which should build seas to
small craft levels. Have undercut wavewatch by a little due to the
uncertainty of this event.

Sub-Small Craft Advisory conditions return for the weekend.

&&

Hydrology...
dry conditions expected through the weekend.

&&

Okx watches/warnings/advisories...
CT...none.
New York...none.
New Jersey...none.
Marine...Small Craft Advisory until 8 PM EDT this evening for anz355.
Small Craft Advisory until 6 am EDT Tuesday for anz350-353.

&&

$$
Synopsis...BC/ln
near term...BC/ln
short term...line
long term...British Columbia
aviation...Nevada
marine...BC/ln
hydrology...line

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