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Area forecast discussion 
National Weather Service New York New York
1225 am EDT Thursday Sep 18 2014

Synopsis...
high pressure remains over the region most of the time through
Sunday. A weak cold front moves through Thursday. Another cold
front moves through the region to start the new week. High
pressure builds back in the wake of the front.

&&

Near term /until 6 am this morning/...
minor changes with this update mainly to reflect temperature and
dewpoint trends. Clear skies and light winds prevail.

Overnight lows will drop into the middle to upper 50s in/around
NYC...and generally in the 40s elsewhere. A few spots across the
interior and The Pine Barrens of Long Island could drop into the
upper 30s.

&&

Short term /6 am this morning through 6 PM Friday/...
the upper and middle level short wave continues to track east through
southern Canada Thursday while a weak cold front moves through the
area during the day. Upper level height begin to rise Thursday
afternoon as another Canadian air mass build toward the region.
Little moisture and lift will be associated with the front and
only an increase in clouds will accompany the passage. Kept probability of precipitation
near zero with the front. Again will be a cool day with northerly
flow and used GFS guidance for highs.

There is a moderate risk of rip current development at the
Atlantic beaches on Thursday.

Thursday night and Friday will remain tranquil as an upper ridge
remains across the eastern third of the United States. And at the
surface high pressure moves out of south central Canada and off
the New England coast. With a much cooler air mass moving in the
NAM and GFS temperature guidance seems a little too high so used
the cooler ecs for temperatures Thursday night and Friday.

&&

Long term /Friday night through Wednesday/...
weekend starts off with high pressure pushing offshore under a near
zonal flow. Generally expecting the dry conditions to continue
Friday night into Saturday with this set up. Partly cloudy skies
over eastern areas with subsidence aloft...increasing cloud cover to
the south and west with weak embedded vorticity maximum riding the flow. 12z
runs of NAM/GFS suggestive of light precipitation formation Sat afternoon though
failing to really see any trigger at the surface or aloft
combining with a still moistening atmo. So will maintain dry probability of precipitation
heading into Sat night.

Changing conditions by Sunday as the next amplifying middle/upper level
trough swings south across the Great Lakes region with surface low
pressure trekking through southern Canada. First thing of note for
Sunday to be addressed is the formation of low pressure forming off
the southeast US with associated middle level energy swings north ahead
of the trough. 12z CMC bit quicker with the progression...allowing
for the phasing of the detached energy with the main trough
developing in a much deeper/stronger system moving through the northeast.
For now...sided with a solution leaning more to the European model (ecmwf) and
GFS...which has the low riding the cold front as it moves through on
sometime Sunday night into Monday...then lingering just offshore
into Monday night and finally exiting the region by Tuesday morning.
Concerning probability of precipitation...introduced slight chance by Sun afternoon for extreme
northwest areas right ahead of the front...then spreading to the
east Sun night and Monday...then tapering off from west to east by
06z Tuesday. Enough moisture should be ushered in with the southerly
flow ahead of the front to result in at least light showers for some
time Sun night-Mon. However...uncertainty on the timing so will
maintain lower end chance probability of precipitation.

Model solutions then come back into decent agreement by 12z
Tuesday...with high pressure building in behind the front...resulting
in dry conditions for middle week.

Period of below normal temperatures will be short lived with warm air advection along the
southerly flow pushing temperatures back to near normal levels by Sat. Cold air advection
with the cold front Monday through middle week will see temperatures dropping
a few degrees below normal once again.

&&

Aviation /06z Thursday through Monday/...
high pressure/VFR through taf period.

Winds weaken and become light west/northwest late. North/northwest winds Thursday
morning...backing west/northwest in the afternoon. Late day sea breeze
possible at kjfk/kbdr/kgon.

Winds shift to north/northwest behind cold front late Thursday evening.

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: northwest winds 7-10 knots likely backing to left of
310 mag in the afternoon. Late day sea breeze possible.

Klga fcster comments: northwest winds 7-10 knots likely backing and
wavering around 310 mag in the afternoon. Occasional gusts into
the middle teens possible in afternoon.

Kewr fcster comments: northwest winds 7-10 knots likely backing and
wavering around 310 mag in the afternoon. Occasional gusts into
the middle teens possible in afternoon.

Kteb fcster comments: no unscheduled amendments expected.

Khpn fcster comments: no unscheduled amendments expected.

Kisp fcster comments: no unscheduled amendments expected.

Outlook for 00z Friday through Monday...
Thursday night-Sunday...VFR.
Sunday night-Monday...chance of MVFR or below with scattered
showers.

&&

Marine...
with high pressure over the waters tonight into Thursday...the
flow will be rather light. A weak cold front does move across the
waters Thursday afternoon into Thursday evening. Another high
builds in from Canada Thursday night into Friday. A northeast flow
around the high increases late Thursday night into Friday. Some
gusts may approach small craft levels on the eastern ocean waters
during Friday. In addition to the flow a southeast swell may allow
for seas on the ocean to build to around 5 feet during Friday.

Generally expecting sub-Small Craft Advisory conditions through the coming week. Seas
will attempt to build to 5 feet on the ocean waters sun-Monday with the
persistent southerly flow...but overall should remain at 3-4 feet.

&&

Hydrology...
no rainfall is expected through the first half of the weekend. No
significant precipitation resulting in hydrologic issues is
expected Sunday through next week.

&&

Okx watches/warnings/advisories...
CT...none.
New York...none.
New Jersey...none.
Marine...none.

&&

$$
Synopsis...Sears/met
near term...jc/mps/met
short term...met
long term...Sears
aviation...Nevada
marine...Sears/met
hydrology...Sears/met

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