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Area forecast discussion 
National Weather Service New York New York
1030 am EDT Thursday Sep 3 2015

a cold front approaches from the north and passes through late in
the day into tonight. High pressure builds down from southeastern
Canada overnight into Friday and remains in control through early
next week. A cold front then moves through the region during the
middle of next week.


Near term /until 6 PM this evening/...
fog off the east end of Long Island is/has lifted. Another hot
late Summer day with moderate humidity. Highs around 90 in/around
NYC and in the middle to upper 80s elsewhere. Surface dewpoints will be
in the middle 60s...thus the heat index will be near the ambient

Have dropped chance for convection until this evening based on
latest short term nwp and surface front still back in Canada.


Short term /6 PM this evening through 6 PM Friday/...
the cold front eventually pushes south of the County Warning Area tonight with
low chances of showers/thunderstorms this evening. A trailing shortwave
pushing south then keeps a slight chance of showers for some
sections during the overnight hours. The shortwave exits to the SW
with an isolated shower still possible Friday morning for
primarily NE New Jersey and the city. Negative vorticity advection...
surface ridging and subsidence should then keep the entire County Warning Area dry
during the afternoon. Models are however showing some lingering
middle level some areas could remain mostly cloudy
through the afternoon...primarily southwestern zones. A mav/NAM
MOS blend looked good for high temperatures and should be 7-10
degrees cooler than today's in most cases.

Although minimum humidity levels should be in the 50s...gusty
east winds Friday afternoon may pose a enhanced concern for spread
of brush fires due to 400-500 kbdi values and available fine
fuels. Along the coast...the potential exists for a high rip
current risk late in the day due to easterly winds and wind waves.


Long term /Friday night through Wednesday/...
gradually increasing drought and fire weather concerns through the

High pressure...both at the surface and aloft...builds over the East
Coast this weekend with the center of the high passing through New
England. With low pressure developing over the southeast U.S. Coast...a
tightening east to northeast gradient will develop over the tri-
state area for Saturday...and then winds shift to more of a
southerly flow for Sunday as the high moves offshore.

Temperatures on Saturday will be right around normal...topping off in the
upper 70s to around 80. With warm air advection underway for
Sunday...highs will climb into the middle and upper 80s.

Bermuda high pressure then strengthens along the East Coast with
increasing heat and humidity for the start of the new week. Highs on
Monday and Tuesday will top off in the middle to upper 80s...and
possibly around 90 for NYC and NE New Jersey. Surface dewpoints will also rise
into the low to middle 60s for much of the area and in the middle to upper
60s for Long Island and southeast CT.

The ridge along the coast breaks down and moves offshore late
Tuesday/Tuesday night...and then a cold front approaches on
Wednesday and moves through during the middle to the end of next


Aviation /14z Thursday through Monday/...
a cold front will approach today...and move across the area

Mainly VFR through the period. Some MVFR visibilities are possible due to
haze. Also...a few isolated showers or thunderstorms will be
possible this evening and early overnight. At this time confidence
in timing/occurrence is too low to place in tafs.

Winds will be light from the north-northeast...and give way to
afternoon seabreezes. Unsure if the seabreeze reaches kteb. Winds
become light and variable throughout again this evening...then
become NE behind the front.

... 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-high confidence in occurrence of
seabreeze. Moderate confidence in timing of seabreeze.

Klga fcster comments: moderate confidence in occurrence of
seabreeze. Low-moderate confidence in timing of seabreeze.

Kewr fcster comments: moderate confidence in occurrence of
seabreeze. Low-moderate confidence in timing of seabreeze.

The afternoon kewr haze potential forecast is yellow...which
implies slant range visibility 4-6sm outside of cloud.

Kteb fcster comments: low confidence of seabreeze occurring this

Khpn fcster comments: moderate confidence in occurrence of

Kisp fcster comments: moderate-high confidence in occurrence of
seabreeze. Moderate confidence in timing of seabreeze.

Outlook for 12z Friday through Monday...
Friday...mainly VFR. Isolated shower/thunderstorm possible
mainly to the west of city terminals into Friday afternoon. NE-east
winds g15-20kt possible.
Friday night...VFR. East-NE winds g15-20kt possible.


dense fog south the east end of Long Island will dissipate by

Relatively tranquil conditions for today and this evening
with a weak surface pressure gradient remaining in place. Winds
then pick up late tonight into Friday as high pressure builds down
from the north...tightening the pressure gradient. There could be
a few gusts up to 25 knots over the ocean waters by late
afternoon...and seas could rise to 5 feet by evening as well over
the eastern ocean waters. Models have trended a little weaker and
later with increasing wavewatch has delayed the onset
of 5 feet seas for the past couple of runs. Add to this that would
be a late third-period event...will therefore hold off on Small Craft Advisory
issuance for now and let the day shift see if trends continue and
issue Small Craft Advisory as necessary.

A tight east to northeast gradient remains over the waters on
Saturday...and wind gusts to 25 knots along with 4-6 feet seas are likely
on the ocean waters before conditions gradually subside Saturday

With high pressure over the waters for the start of the new
week...conditions will remain below Small Craft Advisory criteria.


no widespread significant rainfall is forecast today through the
middle of next week. Drought will continue to develop region wide.
Long Island and southern CT are currently experiencing moderate
drought conditions.


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


near term...tongue
short term...jc
long term...mps
aviation...British Columbia

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