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fxus61 kokx 131422 
afdokx

Area forecast discussion
National Weather Service New York New York
922 am EST Wed Nov 13 2019

Synopsis...
high pressure builds in from the west today, then moves
offshore on Thursday as a weak warm front passes to the north.
This will be followed by a cold front Friday night and high pressure
this weekend. Low pressure may then impact the area Sunday night
into the first part of next week.

&&

Near term /until 6 PM this evening/...
forecast is on track.

Dry, but cold conditions today, as high pressure at the surface
continues to build into the area. The relaxing pressure gradient
will allow winds to diminish through the day.

This Arctic high will continue the very cold temperatures
today. Temperatures at 850 mb will range from -12 c to -15 c,
translating to highs in the upper 20s to lower 30s for the most
part, even under full sunshine. This is cold, for January, let
alone mid-November. Despite the winds diminishing today, wind
chill values will make it feel colder than it really is. Wind
chill values will remain in the teens and 20s, even during the
warmest part of the day.

With high pressure in control, precipitation is not expected.

&&

Short term /6 PM this evening through 6 PM Thursday/...
the main challenge tonight will be in the clouds and thus
temperatures forecast.

Temperatures will fall pretty quickly after sunset, given the
very dry air mass, with dew points in the single digits above
zero. However, as the night progresses and the center of the
high translates offshore, high clouds will lower and thicken.
The timing of these clouds will present the challenge. Right
now, the forecast starts off clear this evening, with partly
cloudy skies after midnight. This would allow temperatures to
drop during the first half of the night and then remain constant
or rise slowly through the second half of the night. But, if
clouds come in later than forecast, temperatures would continue
to fall. If clouds come in sooner, then temperatures would warm
up sooner than forecast.

A return southerly flow sets up for Thursday, sending a warm
front north of the area tonight into Thursday. This, along with
veering profiles in forecast soundings will mean warmer
temperatures for Thursday. However, temperatures will still be
below normal. 850 temperatures suggest highs in the upper 30s
and 40s.

The return flow will also allow for an increase in low level
moistures, models are hinting at some light rain or drizzle by
Thursday afternoon for eastern areas.

&&

Long term /Thursday night through Tuesday/...
the left entrance quadrant of an upper jet streak passes through
Thursday night. This may add some lift along with a low to mid level
shortwave to produce low chances of light rainfall over Li and southeast CT
where shallow moisture remains. The lift and moisture shift east on
Friday with dry conditions across the tri-state area. A cold front
then passes through Friday night with limited moisture and a cold
Canadian air mass behind it. The core of this air mass passes to our
north on Saturday along with the center of high pressure. This will
be the coldest day in the long term forecast with high temperatures
only in the middle and upper 30s in most locations and lows mostly
in the teens and 20s both Friday and Saturday nights.

The high to the north begins to shift into the Canadian Maritimes on
Sunday, and a stacked low drifts NE from the southeast coast. Will
opt for a dry forecast late Saturday night through Sunday as this
setup would produce plenty of dry air in the mid-levels along with
models not showing much in the way of lower to mid level lift where
most of the moisture would be. Moisture then deepens through the
atmospheric column Sunday night into Monday with the storm getting
closer to US as it continues its movement NE. European model (ecmwf) continues to be
farthest west with the track of this storm as compared to
GFS/UKMET/Canadian and would bring likely pops to most of the areas.
Will continue to limit pops in the chance category during this
period - would like to see more model agreement this far out before
raising current pops. Models then diverge further with the timing
and placement of the next coastal low pressure system that develops
in response to deep longwave troughing shifting closer to US and
shortwave energy beginning to round its base. Will therefore
maintain chance pops into Tuesday.

Should this pattern hold, a prolonged east-NE wind flow could
potentially result in at least minor coastal flooding starting
Sunday and continuing with high tide cycles into early next week.
One mitigating factor is that this period will feature relatively
lower astronomical tides as we'll be nearly halfway between a full
and new moon.

&&

Aviation /14z Wednesday through Sunday/...
high pressure continues to build in from the west today.

VFR conditions today with gusty northwest winds. Gusts will generally range
between 20-25 kt, then diminish through the afternoon. Winds
speeds then become light and variable tonight. Winds become
southerly by Thursday morning.

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: occasional wind gusts may be stronger than
forecast this morning.

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

Klga taf comments: occasional wind gusts may be stronger than
forecast this morning.

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

Kewr taf comments: occasional wind gusts may be stronger than
forecast this morning.

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

Kteb taf comments: occasional wind gusts may be stronger than
forecast this morning.

Khpn taf comments: occasional wind gusts may be stronger than
forecast this morning.

Kisp taf comments: occasional wind gusts may be stronger than
forecast this morning.

Outlook for 12z Thursday through Sunday...
Thursday-Friday...VFR. Light S then SW winds Thursday into
Friday.
Friday night...VFR. Northwest wind gusts 20-25 kt.
Saturday-Sunday...VFR. North-NE gusts around 20 kt Saturday.

&&

Marine...
winds have generally diminished to below gale criteria. However,
occasional gusts to 35 kt are possible, especially across the
eastern sound, Peconic and gardiner's bays and the eastern ocean
zones. Therefore, a Small Craft Advisory has been issued everywhere as gusts to
25 kt or greater (but below 35 kt) are still expected across
the waters today.

Winds will continue to diminish rather quickly as the center of
high pressure moves over the coastal waters. All other waters
will fall below 25 kt by the afternoon. Waves will diminish,
with the ocean waters falling below 5 ft by late this afternoon.

Winds and waves remain below Small Craft Advisory criteria tonight through
Thursday.

Sub-Small Craft Advisory conditions are forecast Wednesday night into Friday. A cold
front passage Friday night will result in northerly winds, which
will likely bring Small Craft Advisory conditions back to the area waters. Gale force
gusts are even possible heading into Saturday as the pressure
gradient tightens between high pressure trying to build in from the
north and low pressure taking shape off the southeast coast. The
storm is forecast to head NE through the weekend, so a continued
threat of gale force gusts remains into Sunday.

&&

Hydrology...
no hydrologic impacts expected through the period.

&&

Climate...
record minimum high temperatures for Wednesday November 13th
temperature | year
nyc| 33 | 1911
jfk| 41 | 2013
lga| 39 | 1977
ewr| 41 | 2013
isp| 39 | 2013
bdr| 38 | 1995

Record lows for Wednesday November 13th
temperature | year
nyc| 24 | 1986
jfk| 25 | 1986
lga| 26 | 1986
ewr| 24 | 1986
isp| 24 | 2001
bdr| 23 | 1986

&&

Equipment...
NYC National oceanic and atmospheric administration weather radio station kwo35 (162.55 mhz) is operating
at reduced power until further notice.

&&

Okx watches/warnings/advisories...
CT...none.
New York...none.
New Jersey...none.
Marine...Small Craft Advisory until 1 PM EST this afternoon for anz335-
338-345-353-355.
Small Craft Advisory until 4 PM EST this afternoon for anz330-
340-350.

&&

$$
Synopsis...jc/jp
near term...
short term...jp
long term...jc
aviation...BC/ds

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