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fxus61 kokx 170017 
afdokx

Area forecast discussion
National Weather Service New York New York
717 PM EST Tue Jan 16 2018

Synopsis...
low pressure develops along the mid Atlantic coast tonight and
then passes near or just east of Long Island on Wednesday before
moving up the coast into the Canadian Maritimes Wednesday
night. High pressure will then build to the south through Friday
and move into the western Atlantic this weekend. A cold front
then passes through Monday night into Tuesday morning.

&&

Near term /until 6 am Wednesday morning/...
light snow continues across northwest portions of Orange County. Radar
returns are very light and accumulations have been slow through
the day with a report in Greenville just under an inch. The
steadier precipitation develops after midnight across the
region.

The forecast largely remains on track. The latest 18z models as
well as the latest hrrr and hrrrx support the ongoing forecast
for tonight into Wednesday morning so no major changes have been
made. The biggest challenge continues to lie with the northward
extent of the warmer air and how far the rain/snow line works.
Right now, it appears that it should remain all snow just north
of hpn and dxr, and about 10 to 20 miles to the north and west
of the I-95 corridor in New Jersey.

A prolonged period of southeast winds in the low levels ahead of the
developing low off the mid Atlantic coat tonight will gradually
increase temperatures in the boundary layer. This warming
appears to be sufficient enough for primarily a rain event along
the immediate coast. At the same time, interior sections of the
lower Hudson Valley and southwest Connecticut will be the
recipients of a moderate snowfall event with amounts around
warning criteria. No changes made to the winter weather
headlines from the previous update.

An amplifying upper trough moving across the Ohio Valley
tonight will allow for the forcing to shift to the mid Atlantic
coast tonight, with low pressure developing and tracking
northeast to near or just southeast of Long Island in the
morning. The transition of energy is slow enough that an
inverted trough to the northwest of the low track, extending back into
the Hudson Valley of New York, will allow for an influx of
warmer air ahead of the low.

Temperatures will remain nearly steady overnight and even slowly
rise. Lows will range from the upper 20s in the interior to the
mid 30s along the coast.

&&

Short term /6 am Wednesday morning through Wednesday night/...
low pressure near Long Island in the morning lifts northeast
during the day and up into the Canadian Maritimes by Wednesday
night. Precipitation shuts down across most of the area by late
morning/early afternoon and perhaps ends as period of snow at
the coast. Even if the changeover to snow occurs a bit faster
than indicated in the city/at the coast, limited duration of
precipitation on the backside of the low will limit any
accumulation. Highs will top out in the mid to upper 30s with
northwest winds developing on the backside of the storm. Gust up to 20
mph develop late in the day and possibly linger into first half
of the night.

Cold air will follow for Wednesday night with lows in the teens
inland and around 20 at the coast. This is slightly below
normal.

&&

Long term /Thursday through Tuesday/...
surface high pressure will build to our south on Thursday and
Friday. Meanwhile, an upper trough shifts through with some
shortwave energy Thursday night into Friday. Moisture looks
insufficient for any pcpn, so dry weather is expected. Highs a few
degrees below normal for Thursday, returning to near normal on
Friday. Ridging aloft will then keep the weekend dry with warming
temperatures.

Low pressure enters the Great Lakes region Sunday night, eventually
tracking through Quebec on Tuesday. Some warm advection precipitation may
reach some of the northern zones Sunday night into Monday morning,
which could be in the form of a wintry mix. A cold front otherwise
approaches with increasing chances of rain during the afternoon and
night. Some timing differences still exist among the global models
with the cold front passage, so have capped pops at chance through
Tuesday morning. Rain chances otherwise diminish Tuesday afternoon
with dry weather likely returning Tuesday night. Temperatures Sunday
through Tuesday will remain above normal.

&&

Aviation /00z Wednesday through Sunday/...
a developing coastal low with move north towards the region
overnight, tracking just southeast of Long Island on Wednesday,
and then into the Canadian Maritimes by Wednesday evening.

Conditions expected to gradually lower to MVFR this evening, then
lower to IFR late tonight as precipitation develops across region.
Expect all snow at kswf, which may be moderate at times between
06z and 12z. Rain expected to develop for NYC/New Jersey terminals after
midnight, likely mixing with snow towards daybreak, and then
briefly changing to all snow Wed morning. Khpn/kbdr may see a
mix of rain/snow overnight, before changing to all snow towards
daybreak. All rain expected to for kisp/kgon. Precip taper off
from west to east Wed morning into early afternoon, with conditions
improving to VFR.

East/NE winds less than 10 kt overnight, becoming north/north-northwest towards
daybreak. Winds become west-northwest with gusts 20 to 25 kt Wed afternoon
continuing into eve push, likely averaging just right of 310
magnetic.

New York Metro enhanced aviation weather support...

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

Kjfk taf comments: IFR conds expected with -ra/-sn mix or -sn
for morning push. Snow totals less than 1 inch possible through
Wednesday morning. Winds likely backing from north-northeast to northwest during
the morning push. VFR with northwest gusts 20-25 kt for evening push.

Klga taf comments: IFR conds expected with -ra/-sn mix or -sn
for morning push. Snow totals less than 1 inch possible through
Wednesday morning. Winds likely backing from north-northeast to northwest during
the morning push. VFR with northwest gusts 20-25 kt for evening push.

Kewr taf comments: IFR conds expected with -sn for morning
push. Snow totals of 1-2 inches possible through Wednesday
morning. Winds likely backing from north to northwest during the morning
push. VFR with northwest gusts 20-25 kt for evening push.

Kteb taf comments: IFR conds expected with -sn for morning
push. Snow totals of 1-3 inches possible through Wednesday
morning. Winds likely backing from north to northwest during the morning
push. VFR with northwest gusts to 20 kt for evening push.

Khpn taf comments: LIFR conds expected with -sn for morning
push. Snow totals of 2-4 inches possible through Wednesday
morning. Winds likely backing from north to northwest during the morning
push. VFR with northwest gusts to 20 kt for evening push.

Kisp taf comments: IFR conds with -ra expected for morning
push. Winds likely backing from NE to north during the morning
push. VFR with northwest gusts to 20 kt for evening push.

Outlook for 00z Thursday through Sunday...
Wednesday night-Thursday...VFR. West-northwest winds g20-25kt for Wed eve
push and on Thursday.
Thursday night-Friday...VFR. West-SW winds g20kt possible.
Saturday-Sunday...VFR.

&&

Marine...
Small Craft Advisory in effect for the ocean waters as seas remain 4-5 ft. Ocean
seas increase a bit more tonight. Flow returns to a northwest direction
and begins to gust late on Wednesday.

Small Craft Advisory conditions continue on the ocean for Thursday through Friday
morning, then sub-advisory conditions are expected for a brief
period Friday afternoon and night. Winds and seas then pick up with
marginal advisory conditions on the ocean during Saturday and
Saturday night. A weaker pressure gradient then returns relatively
tranquil conditions for Sunday.

&&

Hydrology...
no significant hydrologic impacts are expected.

&&

Equipment...
NYC National oceanic and atmospheric administration weather radio station kwo-35 (162.55 mhz) is off the
air for an extended period of time.

&&

Okx watches/warnings/advisories...
CT...Winter Weather Advisory from midnight tonight to 1 PM EST
Wednesday for ctz005>008.
New York...Winter Weather Advisory until noon EST Wednesday for nyz069-
070.
Winter Storm Warning until noon EST Wednesday for nyz067-068.
New Jersey...Winter Weather Advisory until noon EST Wednesday for njz002-
004-103>105-107.
Marine...Small Craft Advisory from midnight tonight to 6 am EST
Thursday for anz355.
Small Craft Advisory until 6 am EST Thursday for anz350-353.

&&

$$
Synopsis...jc/dw
near term...dw/ds
short term...dw/ds

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