Area Forecast Discussion
Issued by NWS Upton, NY

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FXUS61 KOKX 230534

Area Forecast Discussion
National Weather Service New York NY
134 AM EDT Tue Jul 23 2019

A frontal boundary remains stalled over the area into Tuesday,
with waves of low pressure developing along it. High pressure
then builds from the west, allowing the boundary to move east of
the area by Wednesday. High pressure remains over the area into
the weekend.


Widespread shower and thunderstorm activity has moved east of
the region, as wave of low pressure along stalled frontal
boundary passes east of the region.

As much as 1 to 3 inches of rain, with locally higher amounts,
have fallen across the area today. Scattered heavy rain showers
and isolated thunderstorms will continue to move across the
area overnight into Tuesday morning, primarily between 7z and
16z. Swaths of rainfall of 1 to 1 1/2 inches are likely with
locally higher amounts possible.

A flash flood watch remains in effect for northeastern New
Jersey, the Lower Hudson Valley, NYC, Nassau County, NY and
the western portion of southeastern Connecticut into Tuesday
morning. The Flood Watch may need to be extended into Tuesday
afternoon. See the hydrology section for more information.

Temperatures will fall into the mid and upper 60s to near 70.


The frontal system will remain over the area, with the threat
for heavy rainfall and locally gusty winds continuing at least
into Tuesday morning, before building high pressure from the
west gradually allows the system to move offshore. With light
winds and recent moisture, fog may develop into Tuesday night.
Expect temperatures to be well below climatological normals on
Tuesday, then closer to normal overnight.

There is a moderate rip current risk for Atlantic Ocean beaches
on Tuesday morning, possibly becoming high in the afternoon.


Strong polar upper low drops into Hudson Bay during the mid to late
week, gradually shearing the closed low currently over Northern
Quebec towards Greenland. The associated deep Eastern US troughing
will slowly weaken through the week as a result, with weak upper
ridging signaled for the weekend ahead of the next closed
shearing eastward just north of the Great lakes.

At the surface, generally tranquil conditions expected, with weak
and elongated high pressure sprawled across the Eastern US in wake
of the offshore cold front slowly drifting eastward. A gradual
moderation in temps expected through the period, starting a
seasonable levels with comfortable humidity mid week and rising to
above seasonal with increasing humidity late week into the


A front will remain near the terminals overnight as waves of
low pressure develop and travel along the front.

Additional showers will affect the TAF sites through this
afternoon. Flight categories may fluctuate over the next few
hours between VFR and MVFR. Generally expect deteriorating cigs
and vsbys with widespread MVFR or lower through much of the TAF
period. VFR conditions are not expected to return until the
middle to late part of Tuesday as a cold front moves across the

Winds remain fairly tricky initially with multiple boundaries
moving across the area. Winds should generally be from the north
less than 10kt, then become light and variable for a period
towards daybreak. Winds are expected to be from the northwest
around 10kt.

.Tuesday afternoon...Scattered showers, with MVFR or lower
conditions expected.
.Wednesday though Saturday...VFR.


A front will remain stalled over the waters at least into
Tuesday, with waves of low pressure passing along it. Any
showers and thunderstorms that develop along or near the
boundary will likely have locally heavy downpours with
visibility restrictions, and the potential for gusty winds.
Winds will remain light outside of any thunderstorms.

A Small Craft Advisory is in effect for ocean seas to continue
at 4 to 6 ft into Tuesday evening.

Marginal SCA seas will be slow to subside through mid week, due
to residual southerly swells, as the slow moving frontal system
crawls east. Otherwise, generally

High pressure begins to build Winds and seas will then remain
tranquil into the weekend with high pressure over the area.


1 1/2 to 3 inches of basin average rainfall occurred across the
region Monday afternoon through Monday evening. Although the
widespread flash flooding threat has diminished for the
overnight, additional scattered heavy rain showers and
thunderstorms moving over already saturated grounds, will cause
localized flash flooding. This will be especially true in areas
of poor drainage, low-lying areas, and in urban areas. A few
fast reacting rivers and streams may see rises once again, with
flooding possible. The flooding threat appears to continue
through midday Tuesday, before rainfall gradually subsides.

The flash flood watch remains in effect for northeastern New
Jersey, the Lower Hudson Valley, and SW Connecticut into
Tuesday morning.

No hydrologic impacts are then expected through the remainder
of the week.


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


CT...Flash Flood Watch until 8 AM EDT this morning for CTZ005-006-
NY...Flash Flood Watch until 8 AM EDT this morning for NYZ067>075-
NJ...Flash Flood Watch until 8 AM EDT this morning for NJZ002-004-
MARINE...Small Craft Advisory for hazardous seas until 6 PM EDT this
     evening for ANZ350-353-355.


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