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Area forecast discussion 
National Weather Service New York New York
152 PM EDT Mon Oct 24 2016

high pressure gradually builds across the region through Wednesday
night. A frontal system approaches from the west on Thursday and
move across Thursday night into early Friday, followed by weak
high pressure later Friday into Saturday. A series of weak frontal
systems will then approach Saturday night into Sunday.


Near term /until 6 PM this evening/...
raised high temperatures into the lower 60s across Long Island,
NYC Metro, and southeast CT where readings have been running a bit warmer
than previously forecast. Have also raised sky cover this
afternoon to account for scattered-broken stratocumulus. This moisture is
trapped below a subsidence inversion around 800 hpa. Increasing
downslope flow should diminish amount of clouds as they push east
and likely will see lower coverage this evening with loss of

Pressure gradient between building high pressure from central
Canada and low pressure across the Canadian Maritimes increases
through the day. Cold air advection and this strong pressure
gradient will lead to gusty northwest winds. Gusts should not be as
strong as Sunday, generally 25 to 30 mph.

Highs will be in the upper 50s and lower 60s, a few degrees below
normal for this time of year.


Short term /6 PM this evening through 6 PM Tuesday/...
still enough of a pressure gradient tonight to allow for steady
winds and wind gusts. Rural locations and other locations away
from the coast will have lighter winds and with mostly clear
conditions anticipated, there will be some radiational cooling.
Min temperatures were taken from a blend of mav/met guidance which
yields a range from just above freezing to the lower 40s. Rural
locations with the lighter winds and generally across the interior
is where frost can be expected. However, frost coverage is only
expected to be patchy.

For Tuesday, there will be continued cold air advection and
another breezy day with a steep pressure gradient between low
pressure to the northeast of the region and high pressure to the
northwest of the region. Cyclonic flow aloft remains. The airmass
will trend drier with a continued northwest flow. Highs again
were taken from the relatively cooler guidance, mav, and will be
several degrees cooler than Max temperatures of the previous day.


Long term /Tuesday night through Sunday/...
high pressure builds into the region Tuesday night and Wednesday.
Expect a dry, cool period as temperatures Tuesday night fall into
the 30s. Wednesday will be sunny with highs in the middle and
upper 40s.

The high pressure system moves offshore Wednesday night. There
should be enough radiational cooling during the first half of the
night to allow temperatures to fall into the 30s, possibly even some
upper 20s, far north and west of NYC. However, during the second
half of the night, clouds increase as a frontal system approaches
from the west. This could limit how cold temperatures get. There
remains some uncertainty with respect to timing of the
precipitation. Some of the models want to bring the precipitation in
between 09z-12z. If this occurs, temperatures should be cold enough
for some wintry precipitation north and west of NYC. For now, will
carry slight chance/chance pops during the morning, with likely pops
by afternoon. Any wintry precipitation that falls, should quickly
change over to rain after 8am or 9am as temperatures quickly warm.
Most of the precipitation that falls with this system falls Thursday
night. If the system moves through as quickly as latest guidance
suggest, Friday could be dry throughout, but will continue to keep
chance pops in for eastern Long Island and southeast CT.

Forecast certainty diminishes after Friday, with big timing
differences noted with a series of frontal systems moving through.
Have only a broad-brush slight chance pop from Sat night into
Sunday, and this could change as the more likely time periods for
rain come into focus in later forecast cycles.


Aviation /18z Monday through Saturday/...
VFR (cig 040-050) this afternoon as high pressure builds over the
region with a gusty northwest wind flow - gusts to around 25 knots through
sunset, then diminishing.

New York Metro enhanced aviation weather support...

Detailed information, including hourly taf wind component forecasts,
can be found at: http:/www.Weather.Gov/zny/n90

Kjfk taf comments: peak winds near or just under 30 knots for the
international departure bank. Wind direction will vary +/- 20 degrees of
fcst, but average at or just right of 310 magnetic.

Klga taf comments: peak winds in the upper 20s knots range this
afternoon. Wind direction will vary +/- 20 degrees of fcst, but average
at or just right of 310 magnetic.

Kewr taf comments: peak winds in the upper 20s knots range this
afternoon. Wind direction will vary +/- 20 degrees of fcst, but average
just right of 310 magnetic.

Kteb taf comments: peak wind gusts in the upper 20s knots range this

Khpn taf comments: peak wind gusts in the upper 20s knots range this

Kisp taf comments: peak wind gusts in the upper 20s knots range this

Outlook for 18z Tuesday through Saturday...
Tuesday afternoon...VFR. Northwest winds g25-30 kt, diminishing Tuesday night.
Wednesday...VFR. Northwest-north-northwest g20 knots possible near the coast.
Thursday...MVFR possible IFR Thursday night in rain. Southeast surface wind 10-20 knots.
Friday...VFR. West-northwest surface wind gusts around 25 knots.
Sat...VFR. Chance -ra. SW surface wind 15-20 knots.


Small Craft Advisory in effect on all waters through Tuesday with a steep pressure
gradient remaining between a low across southeast Canada and
strong high pressure building into the Midwest.

Small Craft Advisory conditions continue on the waters Tuesday night but late at
night will be primarily on the ocean and the eastern sound, and
this could linger possibly into Wed morning. Sub- Small Craft Advisory conditions
are then expected from Wednesday afternoon through much of

SW flow increasing to 15-20 kt Thursday night ahead of a
frontal system should push ocean seas up to 5-6 ft Thu night. Post-
frontal west-northwest flow could gust up to 25 kt on the ocean on Fri as


no widespread significant precipitation is expected through

Thursday and Thursday night, quantitative precipitation forecast from a passing frontal system is
expected to produce anywhere from 1/2 to 3/4 of an inch of rainfall.
Local amounts over an inch are possible. No hydrologic impacts
expected at this time.


Okx watches/warnings/advisories...
New York...none.
New Jersey...none.
Marine...Small Craft Advisory until 6 PM EDT Tuesday for anz330-335-338-


long term...British Columbia

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