Area Forecast Discussion
Issued by NWS Upton, NY

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760
FXUS61 KOKX 030013
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
713 PM EST Fri Dec 2 2016

.SYNOPSIS...
A series of disturbances will push across New England and the
Canadian Maritimes through Saturday night resulting in gusty
northwest winds across the area. High pressure builds Sunday, then
gives way to a weak disturbance Sunday night into Monday. High
pressure builds in late Monday into Tuesday. A frontal system will
approach for the middle of next week.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
Minor updates to temperatures and dewpoints to account for current
conditions. Radar echoes moving south over parts of Connecticut
and the Lower Hudson Valley may produce a sprinkle or two, but
with dewpoint depressions of 10-20 degrees it is unlikely that
much precipitation will reach the ground. Otherwise the forecast
remains on track.

A mid and low-level trough axis was swinging across northern New
England and Upstate New York this afternoon and was helping to set
off light precipitation across Upstate New York as well as advect
in stratus clouds into our area. The stratus has filled in from
west to east today and will remain in place overnight as this
first spoke of energy works across New England toward the Canadian
Maritimes. Dewpoint depressions at the surface are high enough
that it is highly unlikely precipitation could make it to the
ground in our area outside of a sprinkle in Orange or northern
Fairfield and New Haven Counties.

With this trough, winds have picked up ahead of it from the
southwest to west and have been gusty at times especially from The
City north and west. Gusts have reached 37 mph at Stewart Airport
and this should be the higher end of things. However, the surface
pressure gradient will remain tight enough overnight that this
will help to keep winds gusty at times overnight. Lows will be a
little colder than this morning, but given the clouds and wind
drop into the lower 30s in the coldest spots away from The City to
the lower 40s in The City.

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
The first trough and associated energy rotates offshore and is
followed by a second disturbance with associated mid-level energy
that rotates across northern New England toward Boston tomorrow
afternoon into tomorrow evening. As a result, we may get some
breaks in the clouds at times, especially toward the coast as the
flow remains offshore and the northwesterly flow off the terrain
may aid in breaking up some of the lower clouds around. The
surface pressure gradient remains tight and winds in the 925-700
mb level increase to around 35 kts, so gusts again over 30 mph can
be expected through early Saturday evening. Temps will be a little
below normal for highs.

Winds will start to drop off Saturday night as the energy works
offshore and high pressure at the surface combined with mid-level
ridging builds in from the west. Clouds should clear on out and
with less wind, expect a chillier night. The coldest spots well
north and west of The City and in the Pine Barrens of Long Island
will drop into the 20s with readings in The City in the mid to
upper 30s.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
Weak ridge aloft Sunday gives way to weak shortwave and
progressive pattern. Southern stream shortwave moves out of
Mexico, and tracks across Texas Monday before weakening as it
moves quickly across the southeast states Tuesday. Meanwhile,
closed northern stream low moves across central Canada, making
slow progress toward the Great Lakes mid week, then into New
England late in the week.

Differences noted in position and strength of this impressive trough
is moves moves east late in the week.

At the surface, high pressure builds Sunday through Monday. Two
areas of low pressure will form along this frontal boundary. One
over the Southeast that will push off the southeast coast Tuesday
night, then head east. The other will develop over the Ohio Valley
and pass north of the area into Wednesday. These systems
associated with southern stream shortwave mentioned earlier.

Cold air damming signature noted for Tuesday, so precipitation may
start off as snow inland again, then change over to rain, with a
mixture of rain and snow Tuesday night. Again, QPF is expected
to be light.

As for Sunday night, upper trough could result in a few rain/snow
showers as it moves through. ECMWF is much wetter than the other
model solutions, less than a tenth of an inch. Based on this, upped
pops slightly, but would not be surprised to see very little qpf.
Worth watching.

Temperatures will be within a few degrees of normal through mid
week. Temps could jump slightly ahead of late week trough. Then
leaned toward colder numbers Friday, closer to WPC and away from
model blend.

&&

.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
Strong low pressure will slowly drift offshore tonight. Meanwhile
high pressure builds into the Ohio valley.

VFR through the period. SCT-BKN cigs 4-6kft will dissipate
overnight.

Westerly gusts of 20-25 kt...generally left of 310 magnetic are
expected. Gusts are expected to be maintained through the evening
push for NYC/NJ metro terminals...and likely for outlying terminals.
A few peak gusts 25-30 kt are possible until about 02z. Gusts will
periodically drop out for interior TAF sites after 06z.

On Saturday, the gradient tightens and additional NW gusts are
expected. A few NW peak gusts could exceed 30 kt at times by early
afternoon. Winds direction should be very close or just to the
right of 310-320 magnetic during the day. Gusts will start to
decrease after 0z Sunday.

     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: High confidence with wind gusts coming back by
the mid to late morning, with gusts approaching 30 knots into the
afternoon.

KLGA TAF Comments: High confidence with wind gusts coming back by
the mid to late morning, with gusts approaching 30 knots into the
afternoon.

KEWR TAF Comments: High confidence with wind gusts coming back by
the mid to late morning, with gusts approaching 30 knots into the
afternoon.

KTEB TAF Comments: High confidence with wind gusts coming back by
the mid to late morning, with gusts approaching 30 knots into the
afternoon.

KHPN TAF Comments: No unscheduled amendments expected.

KISP TAF Comments: High confidence with wind gusts coming back by
the mid to late morning, with gusts approaching 30 knots into the
afternoon.

.OUTLOOK FOR 18Z SATURDAY THROUGH WEDNESDAY...
.Saturday...VFR. Afternoon NW gusts near 30 kt. Generally right
and very close to 310-320 magnetic.
.Sunday...VFR.
.Monday..VFR...Low chc of early morning MVFR.
.Tuesday...Morning VFR...chc of MVFR in the afternoon.
.Wednesday...Morning MVFR with a mixture of rain and snow for
north and west terminals with rain across southern and eastern
terminals...with chc of sub VFR into the afternoon in rain
showers.

&&

.MARINE...
Gusty northwest winds will continue on the coastal waters through
Saturday afternoon as a series of disturbances works across New
England and the Canadian Maritimes. Given the northwest wind
trajectory, the highest waves will be well offshore as well as
toward the southeast end of The Sound and toward the mouth of New
York Harbor. A Small Craft Advisory was extended through 23Z
Saturday based on a tight pressure gradient and the potential for
winds to gust as high as 30 to perhaps 35 kts. There are fairly
strong winds aloft through Saturday evening, however, an inversion
looks to keep most of the strongest momentum trapped and from
reaching the surface. Wave heights will mainly be 4 to 7 feet on
the ocean. Winds will start to decrease Saturday evening, though
the Small Craft Advisory may need to be extended a but if winds
are slower to drop off.

As high pressure builds Sunday and Monday, winds diminish and seas
remain rather tranquil. Expect conditions to deteriorate Tuesday
into Wednesday as two areas of low pressure approach the waters, and
winds increase ahead of these lows. Seas expected to build, but
lowered forecast below Wave Watch III output.

&&

.HYDROLOGY...
No significant precipitation (greater than a half inch) is
forecast through Monday.

Unsettled weather is possible mid to late week next week. However,
no significant precipitation (greater than a half inch) is forecast
at this time.

&&

.CLIMATE...
The two rounds of rain this week certainly helped with our
drought across the Tri-State area. However, most of the relief was
likely in the area of higher level soil moisture, vegetation and
streamflows with larger reservoirs showing a slight positive
response and smaller reservoirs showing a greater positive
response. Portions of our area - especially over the immediate
City - now show a surplus in the 30 and to a lesser extent 60 day
period. Ironically despite the drought Newark`s November
precipitation total of 6.52 inches was enough to rank it as the
11th wettest November on record dating back to 1931. As deeply
entrenched as the current drought has been, it will certainly not
break quickly but any trend toward a wetter pattern will certainly
help things improve or at least keep them from getting worse.

We still have yet to hit freezing this fall at Central Park. There
have only been 11 seasons counting this year back to 1871 where
the first freeze of the season held off until December. The latest
first freeze ever at The Park was back in the very warm of
December of 1998 (which as a La Nina episode) and did not take
place until the 22nd.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory until 6 PM EST Saturday for ANZ330-335-
     338-340-345-350-353-355.

&&

$$
SYNOPSIS...CS
NEAR TERM...FEB/CS
SHORT TERM...CS
LONG TERM...PW
AVIATION...JE
MARINE...PW/CS
HYDROLOGY...PW/CS
CLIMATE...



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