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000 
FXUS61 KOKX 230752
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
352 AM EDT Wed Oct 23 2019

.SYNOPSIS...
High pressure builds in from the southwest through Thursday. 
High pressure for the end of the work week gives way to a broad 
area of low pressure that will affect the area for the second 
half of the weekend. High pressure then returns for the start of
the new work week.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Broad CONUS troughing dominates, with a deep closed low drifting
towards Hudsons Bay and its associated shortwave trough swinging 
through the region this morning.

At the surface, the frontal system affecting E LI/CT with some
locally heavy showers this morning moves east of Long Island by
around 12z, with high pressure building to the SW of the region
in its wake. Rain will come to an end across far eastern areas 
by around 6-8 am. Clouds scatter from w to e through this 
morning, giving way to sunny skies this afternoon from 
drying and subsidence in wake of shortwave.

Above seasonable temps expected today due to mild start, breezy
downslope flow, sunshine and gradual caa. Highs generally in 
the mid 60s, with a few upper 60s for NYC/NJ metro and coastal 
plain. 

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
Deep SW flow expected in between an amplifying Central US 
trough and Bermuda upper ridging. At the surface, high pressure 
builds in to the south of the area tonight into Thursday, 
providing a moderating SW flow to the region. 

Good radiational cooling conds tonight across far outlying areas 
with clear skies and decoupling. This should allow temps to drop 
into the mid to upper 30s across the interior and pine barrens,
wit patchy frost development. A slight onshore flow should help
keep temps near seasonable in the 40s for the rest of the 
coastal plain and urban areas.

Fair and unseasonably mild on Thursday in SW flow regime. Highs
once again averaging in the mid 60s.

&&

.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
Dry weather is expected to start off the long term period with 
surface high pressure centered south of the area. Farther west, an 
amplifying trough begins to eject out of the Rockies Thursday night 
before the flow splits during the day on Friday.

As the flow aloft splits, this will send a northern stream shortwave 
towards the region late in the day on Friday into Friday night. 
Models continue to disagree on the degree of amplification this 
shortwave will be able to achieve as it approaches the area, but it 
should result in a slight chance to chance of showers Friday evening 
into Friday night, primarily north of New York City. 

Once the shortwave passes, attention then turns to the upper low 
over the southern plains. Notable timing differences still remain 
between the models in terms of how quickly this system ejects 
northeast towards the Great Lakes, with the GFS bringing 
precipitation into areas west of NYC as early as Saturday afternoon 
while most of the other guidance holds off on any precipitation 
until overnight. Given the tendency of the GFS to be too fast in 
these situations, think the daylight hours on Saturday should remain 
dry, with rain moving in from west to east after sunset. Rain then 
continues through the day on Sunday before tapering off Sunday night.

High pressure returns at least briefly on Monday. The next chance of 
rain is possible again as early as Monday night as another trough 
begins to dig into the central U.S., but again think models are 
likely too fast with this system and any associated precipitation 
for the local area.

Temperatures through the period are expected to be near to a few 
degrees above normal, with daytime highs generally ranging from the 
upper 50s to mid 60s and overnight lows ranging from around 40 in 
outlying areas to the lower 50s in the New York City metro.

&&

.AVIATION /07Z WEDNESDAY THROUGH SUNDAY/...
Low pressure system with a trailing cold front continues to move 
across the local region. Rain showers are quickly ending from west 
to east and winds becoming northwesterly behind the front. In 
addition, conditions have improved to MVFR/VFR at the NYC terminals 
and points west. East of NYC, conditions remain IFR or less. 
Conditions will continue to improve through 10-12z, with VFR 
expected everywhere by 12z, and remaining VFR through the TAF period.

Winds become northerly behind the cold front through 12z and 
northwesterly Wednesday afternoon with gusts near 20kt possible. 

.OUTLOOK FOR 06Z THURSDAY THROUGH SUNDAY...
.Wednesday night-Thursday...VFR.
.Friday-Saturday...Chc MVFR and rain Fri PM into SAT AM.

&&

.MARINE...
Marginal SCA gusts on all waters today, with gusty WNW flow in 
wake of cold front. 3-4 ft easterly swells and 2-4 ft W wind 
waves will maintain SCA conds on the ocean today. Winds will 
gradually subside this evening into tonight as high pressure 
moves towards the region, with waves quickly subsiding below 
SCA as well.

Sub SCA conds expected on Thursday with high pressure building 
to the south, and wind and seas continuing to subside.

Winds and seas will continue to remain below Small Craft Advisory 
criteria through Saturday. By Saturday night into Sunday, winds will 
increase to 25 kt on the ocean, eastern Sound, and Bays as an area 
of low pressure approaches the waters. In addition, seas on the 
ocean could increase to 5-8 ft on Sunday. Gusts will begin to 
subside Sunday night as the low moves off to the northeast, although 
seas will remain elevated through much of the day on Monday.

&&

.HYDROLOGY...
No hydrologic impacts are anticipated through this week. 
Rainfall amounts with a weekend system could approach one inch,
but predictability remains low at this time.

&&

.EQUIPMENT...
NYC NOAA Weather Radio Station KWO35 (162.55 MHz) remains off the
air.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory until 8 PM EDT this evening for ANZ350-
     353-355.

&&

$$
SYNOPSIS...FEB/NV
NEAR TERM...NV
SHORT TERM...NV
LONG TERM...FEB

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