Area Forecast Discussion
Issued by NWS Upton, NY

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FXUS61 KOKX 062344

Area Forecast Discussion
National Weather Service New York NY
644 PM EST Fri Dec 6 2019

A cold front passes through the area this evening. High
pressure will follow for Saturday and then build offshore on
Sunday. A slow moving frontal system will affect the area
through mid week, followed by arctic high pressure late in the


Cold front passing across the western half of the CWA this
evening. Northern stream shortwave passes across New England
tonight, and associated clipper system departs east of New
England as the front moves to the east.

Limited moisture and upper dynamics noted, with any lingering
light shower activity ending quickly this evening.

Gusty W/SW winds ahead of the front shift to WNW in its wake.
Gusts of 20-30 mph likely ahead of and behind the front,
ushering in a Canadian airmass with slightly below seasonable
temps. Generally mid 20s interior, upper 20s to lower 30s


Northern stream trough amplifies over the region Saturday,
sliding east Saturday Night, with weak upper ridging building in
for Sunday.

Mostly sunny, dry and unseasonably cool conditions Saturday as
Canadian high pressure builds overhead. High generally in the
lower 30s Interior, and mid to upper 30s city/coast. Occasional
NW gusts to 15 to 20 mph possible.

Potential for strong radiational cooling conds Saturday Night
with high pressure overhead. Lows well down into the lower teens
across Interior, particularly where snowpack lingers, as well
as pine barrens of LI. Otherwise, lows generally in the upper
teens to lower 20s coast, mid 20`s city.

High pressure slides offshore Sunday, with developing return
flow and temperatures moderating a bit. Another dry day, with
increasing high clouds filtering in with PAC flow. Highs
generally upper 30s to lower 40s, but still a few degrees below


Large upper trough moves out of the west and across the middle
of the country early next week, with good model consensus. The
trough axis passes Thursday as it lifts northeastward, with
rising heights by late in the week.

At the surface, high pressure continues to move well to the
east as waves of low pressure ride along a front over the mid
west to the northeast. As these waves of low pressure ride along
the front toward the Great Lakes region, a warm front lifts
north of the area Monday. Rain chances increase Sunday night
into Monday ahead of this warm front, and in strong WAA and
increasing lift, along with plenty of sub tropical moisture. The
cold front will approach the area Tuesday, and model consensus
tracks the front across the area Tuesday night. The front moves
slowly east Wednesday, with a lingering sfc trough possibly
passing through Wednesday late in the day or at night. High
pressure then builds behind, ushering in the coldest air of the

As for sensible weather, showers on Tuesday and Tuesday night
taper off early Wednesday, with some difference in the models
with amount of post frontal precip lingering ahead of slow
moving trough Wednesday. Depending on amount of precip behind
the front, enough cold air could result in a period of wintry
weather Wednesday morning.

Gusty southerly winds will result in mild temperatures Sunday
night (rising) and Monday. This mild air remains in placed ahead
of the cold front Monday night and Tuesday, before temperatures
fall back Tuesday night and Wednesday. Very cold air will
settle in Wednesday night and Thursday, with temps likely remain
below freezing. A slight warmup is expected by Friday as the
high passes east.

Total QPF amounts of 1-3 inches is expected with this long
duration event, Sunday night-Wednesday morning. 6Z GEFS plumes
show this spread, with mean right around 1 1/2 inches.


Predominately VFR conditions expected through the forecast
period. 5kft ceilings will give way to mostly clear skies
following a cold front pushing south through the region late
this evening during the overnight hours.

Fairly high confidence in winds 10-15 G20-25kt this evening but
may be a brief lull as the front passes through. Timing of
fropa roughly 01Z NYC metros and 01Z-02Z east, with winds
shifting WNW at first and then right of 310 mag toward midnight.

.Saturday and Sunday...VFR.
.Sunday night and Monday...Rain showers likely with MVFR or lower
.Tuesday...MVFR or IFR in rain, with conditions improving late
at night.
.Wednesday...VFR. NW G30kt possible.


A Gale warning remains in effect for the ocean waters with SCA
conditions elsewhere into tonight with winds continuing to ramp
up ahead of an approaching cold front. The cold front passes
through the waters this evening. Gusts of 30 to 35 kt
diminish to below SCA by daybreak Saturday as high pressure
builds in from the west. SCA waves may linger a bit on the
eastern ocean waters Saturday morning, before falling below SCA.
Otherwise, sub-SCA conds through Sunday as high pressure moves

Southerly winds increase Sunday night into Monday as the
pressure gradient tightens between the departing high to the
east and cold front to the west. As the front draws closer, the
southerly flow will increase late Monday into Monday night, with
gusts 25-35 kt or near gale force for eastern waters. Winds
diminish somewhat as the front nears and passes Tuesday, Tuesday
night and possibly into Wednesday. Winds should increase as
they turn to the west/northwest late Wednesday.

Seas will builds Sunday night and Monday in strengthening
southerly flow. Seas will subside slowly Tuesday-Wednesday as
the cold front passes and winds diminish somewhat.


No significant liquid equivalent is forecast through Sunday.

A significant long duration rainfall event is expected later
Sunday night, continuing through Tuesday night. There will be
some lulls in the precipitation, but the rain could be heavy at
times Monday and Monday night, and again later Tuesday. The long
duration of the event should preclude widespread flooding.
Nuisance/poor drainage flooding is the most likely outcome.


NYC NOAA Weather Radio Station KWO35 (162.55 MHz) is still
operating at reduced power.

The KOKX WSR-88D radar will be out of service until
approximately 12/7 due to the refurbishment of the transmitter.
This work is part of the NEXRAD Service Life Extension Program.


MARINE...Small Craft Advisory until 3 AM EST Saturday for ANZ330-335-
     Gale Warning until midnight EST tonight for ANZ350-353-355.


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