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fxus61 kokx 221613 
afdokx

Area forecast discussion
National Weather Service New York New York
1113 am EST Fri Nov 22 2019

Synopsis...
a cold front will move through the area this afternoon. High
pressure will then briefly return for Saturday. Next low
pressure system brings moderate rain Saturday evening and all
day Sunday. Weak high pressure then builds in for Monday through
the middle of next week. A cold front will move through late
Wednesday into Wednesday night.

&&

Near term /until 6 PM this evening/...
probabilities have been adjusted based on the 12z href.
Otherwise, no major changes were made to the forecast.
Shortwave trough extending south through the Ohio River valley
pivots across New York state today. This trough brings with it
significant positive vorticity advection and dynamically driven lift through the region
which will act as the main lifting mechanism for precipitation
this afternoon. Temperatures in the afternoon will be relatively
mild reaching the mid 50s before the expected rain.
Precipitable water values prior to the cold front are around
0.60-0.90 inches which is slightly more than the 75% moving
average according to the Storm Prediction Center sounding climatology. Meaning there
is a fair amount of ambient moisture to generate light to
moderate rainfall. Rainfall totals range from 0.10-0.25 inches
with the larger amounts expected east of the NYC Metro.

&&

Short term /6 PM this evening through Sunday night/...
following the cold front, conditions will be breezy with
dewpoints dropping into the low 20s with overnight low
temperatures falling into the low 30s and upper 20s. The high
pressure system and associated cold airmass shifts overhead as a
mid- level ridge builds from the west. A chilly Saturday is
still expected despite the clear skies with temperatures only
reaching the mid 40s by the afternoon.

Towards the evening and overnight hours on Saturday a shortwave
trough and deepening low pressure system near the Appalachian
Mountains will have to be monitored for the next batch of
impactful weather. Initially, as the system nears the lower
Hudson Valley, precipitation falling through the residual cold
airmass may be able to refreeze prior to reaching the surface.
This is most likely in the northwest portion of Orange County
late Saturday night into early Sunday morning with little to no
accumulation of freezing rain or sleet expected. A steady cold
rain is expected for the rest of the forecast area through the
day. Precipitable water values around 1 inch will allow for ample rainfall
Sunday. Quantitative precipitation forecast totals between 1.00-1.50 inches with isolated higher
amounts will be possible. This could lead to nuisance street
flooding and ponding of water in poor drainage areas.

The aforementioned low pressure system exits to the northeast by
the late evening allowing a stable dry airmass to enter the
forecast area overnight.

&&

Long term /Monday through Thursday/...
weak surface ridging builds in from high pressure over the Gulf
of Mexico Monday, then pushes offshore on Tuesday.

A frontal system approaches for the middle of the week, lifting a
warm front north of the area Tuesday night into early Wednesday
morning. The associated cold front quickly moves through Wednesday
into Wednesday night as the associated low passes well north and
east of the area, tracking over the eastern Great Lakes region then
into southeastern Canada. Temperatures will be warm enough at this
point for all rain everywhere.

&&

Aviation /16z Friday through Tuesday/...
a cold front approaches this morning, and passes across the area
this afternoon. High pressure builds to the south and west tonight.

VFR conditions are expected this morning. Brief MVFR conditions are
possible in showers, generally during the 15-21z timeframe, west to
east. VFR prevails this evening through Saturday morning.

SW winds increase this morning, and gusts become more frequent late
this morning, 14-16z. Winds veer to the west briefly, then
west/northwest after 18-20z. Gusts of 25-30 kt are expected late
this afternoon and evening. Gusts should gradually diminish tonight,
ending early Saturday morning. Northwest winds veer to the west Saturday
morning under 10 kt.

... 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: gusts could be occasional 14z-16z. Timing of wind
shift to the northwest may be off 1-2 hours this afternoon. Low chance for
IFR in showers this afternoon.

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

Klga taf comments: gusts could be occasional 14z-16z. Timing of wind
shift to the northwest may be off 1-2 hours this afternoon. Low chance for
IFR in showers this afternoon.

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

Kewr taf comments: gusts could be occasional 14z-16z. Timing of wind
shift to the northwest may be off 1-2 hours this afternoon. Low chance for
IFR in showers this afternoon.

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

Kteb taf comments: gusts could be occasional 15z-18z. Timing of wind
shift to the northwest may be off 1-2 hours this afternoon. Low chance for
IFR in showers this afternoon.

Khpn taf comments: gusts could be occasional 15z-18z. Timing of wind
shift to the northwest may be off 1-2 hours this afternoon. Low chance for
IFR in showers this afternoon.

Kisp taf comments: gusts could be occasional 14z-16z. Timing of wind
shift to the northwest may be off 1-2 hours this afternoon. Low chance for
IFR in showers this afternoon.

Outlook for 12z Saturday through Tuesday...
Saturday...VFR.
Saturday night...IFR in rain. Chance of freezing rain at kswf.
Sunday...rain with MVFR/IFR. Northwest winds gusting to around 20-30 kt in
the afternoon and evening.
Sunday night-Tuesday...VFR.

&&

Marine...
SW flow ahead of an approaching cold front continues to increase on
the waters this morning. Small Craft Advisory conditions will develop through the
morning. The cold front moves across the waters in the afternoon
with winds becoming west-northwest and should be well east by early evening.
Gale force winds are likely in the afternoon and evening on the
waters east of Fire Island Inlet, eastern Li bays, and eastern Li
sound. An occasional gale gust cannot be ruled out west of Fire
Island Inlet. Gale warnings and small craft advisories are in
effect. Ocean seas will also build to 5 to 8 ft, highest east of
Moriches Inlet. Winds slowly decrease overnight from west to east as
high pressure builds to the south and west. Winds should be below
Small Craft Advisory levels early Saturday morning. Seas also subside below Small Craft Advisory
levels through tonight.

Sub-Small Craft Advisory conditions will occur on Saturday with high pressure near
the waters. These conditions should continue into Saturday night
with intensifying low pressure approaching the waters. The low moves
across the waters Sunday morning and early afternoon and then
quickly north and east away from the New England coast Sunday
evening. Winds and seas should remain below Small Craft Advisory levels in the
morning, but increasing northwest winds on the backside of the low should
bring Small Craft Advisory winds on all waters with potential for gale gusts on the
ocean. Seas will also build in the afternoon as the low passes east.
Elevated seas are then possible due to lingering swell into Monday
morning. Otherwise, sub-Small Craft Advisory conditions are likely with high pressure
over the waters.

&&

Hydrology...
no hydrological concerns are expected through Saturday. Liquid
equivalent amounts of 1.00"-1.50" are forecast from late
Saturday into late Sunday as an area of low pressure impacts the
region. There is some uncertainty with the amounts depending on
the track and intensity of the low.

&&

Tides/coastal flooding...
astronomical tides will be increasing late this weekend due to a new
moon early next week. An intensifying, fast moving low pressure
system will also move across the region on Saturday night into
Sunday. The quick movement of the system should prevent significant
coastal impacts. However, minor coastal flooding is possible with
Sunday morning high tide across the South Shore back bays and Sunday
afternoon high tide across the western sound.

Minor flooding benchmarks may be reached early next week due to
the new moon.

&&

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 5 am EST Saturday for anz335-338-
345-355.
Gale Warning until midnight EST tonight for anz330-340-350-353.

&&

$$
Synopsis...dj/16
near term...
short term...dj/16
long term...dj/16
aviation...ds

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