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fxus61 kokx 121308 
afdokx

Area forecast discussion
National Weather Service New York New York
808 am EST Tue Nov 12 2019

Synopsis...
a strong cold front will move through the area this morning.
High pressure builds in from the west through Wednesday, 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 the first part of next week.

&&

Near term /until 6 PM this evening/...
forecast on track this morning just just a few minor adjustments
to reflect the latest observations. Also, one minor change made
was to slow down the cold air across the far eastern portions
of the County Warning Area. This was based on the latest hi-res models.

Otherwise, a cold front will move through the forecast area
this morning, as an area of low pressure develops along
boundary, passing well north and east of the area. The cold
front is expected to be offshore by late this morning into the
early afternoon hours. A non-diurnal temperature forecast for
today as temperatures are expected to drop immediately behind
the front. Temperatures in the 40s and 50s for much of the area
will drop to the 30s and 40s by early afternoon, and 20s and 30s
by early this evening.

Precipitation will largely be behind the front, starting off as
rain. The rain will mix with or change over to all snow briefly
before ending, with the best chances for a changeover across
inland areas. However, with such light amounts of precipitation
forecast (less than a 0.25" for the entire forecast area, a
tenth of an inch for New York City and points north and west),
not expecting a lot in the way of accumulations, if at all. A
dusting to a coating is possible, again, mainly for inland
areas. However, some mesoscale models are indicating some
enhancement in precipitation as the precipitation band moves
east and the low strengthens, with some accumulating snows
across southeast Connecticut and eastern Long Island. Will have
to continue to monitor this, but again, less than an inch is
expected.

Of some concern would be the potential for black ice as the
colder air moves in allowing any standing water to freeze.
However, windy conditions due to the strengthening low (gusts
of 35 to 40 mph are possible, allowing for evaporation) and low
forecast precipitation amounts may preclude this from happening.
Will continue to monitor for the potential of an Special Weather Statement.

&&

Short term /6 PM this evening through 6 PM Wednesday/...
conditions will continue to be windy tonight, especially along
coastal areas. Winds will slowly diminish overnight. However,
with near record lows forecast Tuesday night into Wednesday
morning (see climate section below), wind chill values will
range from the teens and single digits above zero across
coastal areas, to either side of zero inland. Actual lows will
be in the teens and 20s.

Wednesday will continue to be breezy, again, especially along
the coast. Temperatures will not get out of the lower to middle
30s. Combined with the winds, it will feel more like the 20s
during the warmest part of the day.

&&

Long term /Wednesday night through Monday/...
high pressure will build over the area Wednesday night. Light winds
and clear skies Wednesday night will allow for good radiational
cooling, as temperatures fall into the teens and 20s.

The high slides offshore on Thursday, allowing winds to become more
southerly as a warm front lifts north across the region.
Temperatures on Thursday will reach the upper 30s and 40s.

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 what we see
over the next two days. 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 through
Tuesday.

&&

Aviation /13z Tuesday through Saturday/...
a cold front continues to move across the terminals this morning.

Mostly MVFR in rain this morning, however IFR possible due to visibilities
in -sn or -rasn. Rain ends in a brief mix with snow for most
terminals, but a longer period of snow is more likely for kswf. VFR
returns this afternoon with the end of precipitation.

Northwest winds increasing 15-20 kt for the afternoon and evening with
gusts around 30 kt.

..NY 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: MVFR duration may be shorter than forecast. Rain
could end a couple hours before forecast, and snow might not have a
chance to mix in upon precip ending.

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

Klga taf comments: MVFR duration may be shorter than forecast. Rain
could end a couple hours before forecast, and snow might not have a
chance to mix in upon precip ending.

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

Kewr taf comments: MVFR duration may be shorter than forecast. Rain
could end a couple hours before forecast, and snow might not have a
chance to mix in upon precip ending.

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

Kteb taf comments: MVFR duration may be shorter than forecast. Rain
could end a couple hours before forecast, and snow might not have a
chance to mix in upon precip ending.

Khpn taf comments: MVFR duration may be shorter than forecast. Rain
could end a couple hours before forecast

Kisp taf comments:mvfr duration may be shorter than forecast. Rain
could end a couple hours before forecast

Outlook for 12z Wednesday through Saturday...
Wednesday...VFR. Northwest winds g25-30 kt Tuesday night and northwest winds g20-
25 kt Wednesday. Winds diminish Wednesday night.
Thursday-Saturday...VFR. Northwest gusts 15-20 kt Friday night. North-NE gusts
15-20 kt Saturday.

&&

Marine...
winds will increase today with Small Craft Advisory conditions
continuing on the ocean waters, and then across the remainder
of the waters by daybreak this morning. Winds shift from the
west to the northwest with the passage of the cold front early
this morning. Gusts will increase across all the waters.
Occasional gale gusts are possible by late this afternoon
across the ocean waters, with more frequent gale gusts tonight.
A Gale Warning remains in effect for the ocean waters, and the
eastern sound and eastern Long Island bays. Small Craft Advisory remains in
effect through Tuesday night across the remainder of the
waters. Winds and gusts will begin diminishing late Tuesday
night into Wednesday. Seas will build to 5 to 9 ft across the
ocean waters, and 3 to 5 ft for the eastern sound. Waves
diminish tonight, falling below Small Craft Advisory criteria on the ocean by
late Wednesday afternoon.

Sub-Small Craft Advisory conditions are forecast Wednesday night into Friday. A cold
frontal passage Friday night will result in northerly winds, which
will likely bring Small Craft Advisory conditions back to the area 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 until 6 am EST Wednesday for anz335-338-
345.
Small Craft Advisory until 6 PM EST this evening for anz330-
340-350-353-355.
Gale Warning from 6 PM this evening to 6 am EST Wednesday for
anz330-340-350-353-355.

&&

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

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