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fxus61 kokx 112146 
afdokx

Area forecast discussion
National Weather Service New York New York
446 PM EST Mon Nov 11 2019

Synopsis...
low pressure moving out of the Ohio Valley passes across the
region tonight through Tuesday, bringing a strong cold front
through by late Tuesday. High pressure builds in from the west
Tuesday night. The high will build across the area Wednesday
and then offshore on Thursday as a weak warm front passes
through. This will be followed up by another cold frontal
passage Friday night and high pressure next weekend. Low
pressure may impact the area late Sunday into Monday.

&&

Near term /until 6 PM Tuesday/...
guidance has come into better agreement with the timing and
movement of low pressure moving through the northeast through
Tuesday, and the associated full latitude upper eastern trough.
Precipitation remains confined to the cold frontal boundary,
mainly behind the front. With that, much of tonight will be dry,
with precipitation moving into the western zones after
midnight. With boundary temperatures remaining relatively warm
precipitation will begin as rain. The low and cold front will
remain progressive and the period of precipitation will be
confined to Tuesday. The challenge is how quickly the colder air
moves into the area before the precipitation shuts off. The
trend has been for a slower and more brief period of changeover.
Will basically have chance and slight chance probabilities with
the mix and changeover to snow.

Temperatures during Tuesday will also be a challenge and timing
of the colder air will have an impact on the changeover. The
front moves into the western zones by late Tuesday morning and
through the area during the afternoon. High temperatures across
the western zones will probably be first thing in the morning,
and with highs only a few degrees above Monday night lows across
the rest of the forecast area. Temperatures hold steady then
begin the sharp drop in the afternoon into Tuesday night.

&&

Short term /6 PM Tuesday through Tuesday night/...
temperatures continue to fall sharply Tuesday evening, and
record cold for Tuesday will be possible just before midnight.
Precipitation may linger across the Twin Forks in the very early
evening hours. However, the trend is for a quicker ending. The
upper trough will be across the east with the trough axis
passing through late Tuesday night as heights begin to rise. At
the surface high pressure will be building to the west and a
strong pressure gradient force will exit between the high and
the departing low. Gusty northwest winds will result in winds
chills in the single digits above zero to around 10 above across
the region. Record lows will be possible Wednesday morning. See
the climate section for details on the records.

&&

Long term /Wednesday through Monday/...
the long term period starts off with an early season Arctic
airmass bringing record cold to the area through Wednesday
night. Both highs and lows will be around 20 degrees below
normal with the possibility that temperatures do not get above
freezing Wednesday afternoon. This is due to a high amplified
upper flow with ridging across the West Coast extending
northward into Alaska with deep-layered northwest flow feeding
into the mean trough across eastern North America. The upper
level low associated with the pool of Arctic air will lift into
eastern Canada Wednesday, so this will be a quick shot of cold
air.

High pressure will then build across the area Wednesday night
and offshore on Thursday. A weak warm front will move across the
region late Thursday. This still looks to be a dry frontal
passage but a sprinkle or flurry can't completely be ruled out.

Another cold frontal passage is on track for the end of the
week, but the airmass this time around will not be as cold as
the previous midweek shot. Low pressure may impact the region
late Sunday into early next week as an upper low along the
southeast coast gets drawn northward ahead of an upper trough
moving across the Mississippi Valley. Temperatures moderate
Sunday into Monday.

&&

Aviation /21z Monday through Saturday/...
low pressure moves across the terminals tonight. A strong cold
front passes on Tuesday.

VFR into the first half of tonight. Light winds will continue to
become S-southeast under 10 kt. The winds shift to the SW tonight and then
gradually increase into early Tuesday morning.

Rain develops around daybreak with conditions lowering to MVFR.
Winds will shift to the northwest and become gusty. Gusts 20-30 kt are
likely, especially into the late morning and afternoon. The rain may
mix with some light snow as the precipitation ends. However, it will
be brief and no accumulation is anticipated at NYC, Long Island, and
Connecticut terminals. Kswf may change to all snow and a light
accumulation is possible by midday.

Conditions return to VFR from west to east Tuesday afternoon.

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: no unscheduled amendments expected.

Klga taf comments: no unscheduled amendments expected.

Kewr taf comments: no unscheduled amendments expected.

Kteb taf comments: no unscheduled amendments expected.

Khpn taf comments: no unscheduled amendments expected.

Kisp taf comments: no unscheduled amendments expected.

Outlook for 18z Tuesday through Saturday...
Tuesday afternoon...MVFR with rain/mixed precip early, VFR with northwest
gusts 25-30 kt PM.
Tuesday night-Wednesday...VFR. Northwest winds g25-30 kt Tuesday night and
northwest winds g20-25 kt Wednesday. Winds diminish Wednesday night.
Thursday-Saturday...mainly VFR.

&&

Marine...
southerly winds will be increasing ahead of a low that will
track west and north of the forecast waters through Tuesday,
with an associated cold front passing through Tuesday. Small
Craft Advisory conditions are expected to develop on the ocean
waters this evening, and then across the remainder of the waters
overnight. With the passage of the cold front winds shift to the
west and northwest with winds and gusts increasing across all
the waters. Gale gusts may be possible by late afternoon across
portions of the ocean waters, however, confidence was not high
enough to begin the warning. Gale gusts will be likely Tuesday
night, and a Gale Warning was posted for the ocean waters, and
the eastern sound and eastern Long Island bays. Then the Small Craft Advisory was
extended through Tuesday night across the remainder of the
waters. Winds and gusts will begin diminishing late Tuesday
night.

Winds will gradually subside on Wednesday as high pressure
builds in from the west. Sub-Small Craft Advisory conditions are forecast
Wednesday night into Friday. Following a cold frontal passage
Friday night, northerly winds will likely bring Small Craft Advisory conditions
back to the waters.

&&

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

&&

Climate...
record lows for Tuesday November 12th
temperature | year
nyc| 26 | 1926
jfk| 29 | 2017
lga| 32 | 2013
ewr| 28 | 2017
isp| 25 | 2001
bdr| 28 | 1957, 2013

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 from 1 am Tuesday to 6 am EST Wednesday
for anz335-338-345.
Small Craft Advisory from 1 am to 6 PM EST Tuesday for anz330-
340.
Gale Warning from 6 PM Tuesday to 6 am EST Wednesday for
anz330-340-350-353-355.
Small Craft Advisory until 6 PM EST Tuesday for anz350-353-355.

&&

$$
Synopsis...19/dw
near term...19
short term...19
long term...dw
aviation...ds

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