Area Forecast Discussion
Issued by NWS Upton, NY

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FXUS61 KOKX 261556

Area Forecast Discussion
National Weather Service New York NY
1156 AM EDT Wed Apr 26 2017

Weakening low pressure near the Delmarva this morning tracks
very slowly northeast today, passing southeast of Long Island
tonight. The low dissipates along the New England coast on
Thursday. A weakening cold front will approach from the northwest
Thursday and Thursday night, then also dissipates over the area
on Friday. Another cold front pushes south of the area Saturday
night. This front then moves back toward the area as a warm
front Sunday night into Monday with the associated cold front
moving through Monday night into Tuesday morning.


Main area of moderate rain showers across parts of Southern CT
into the Western Lower Hudson Valley with otherwise light rain
showers across other parts of the region. There is some patchy
fog mainly across Southeast CT and Eastern Long Island, which
is locally dense this morning. Temperatures and dewpoints are
pretty much right on track.

A closed upper low near the Delmarva this morning will lift
slowly NE today, in tandem with the surface low. This will keep
the area under a weak NE flow.

Weak lift and saturated low levels will result in light rain
and/or drizzle for much of the day. In addition, with the
diminishing NE flow and saturated low-levels, there will be some
patchy fog.

Highs today will be near normal in the lower 60s.


Weakening low pressure passes to the south and east of Long
Island tonight and dissipates along the New England coast on

Low-levels will remain moist with light NE winds. Widespread fog
and drizzle is forecast tonight. The fog may even become dense
overnight before gradually lifting on Thursday.

With a subsidence inversion on Thursday and the development of
a weak return SE flow, low clouds are likely to persist through
the day.

Overnight lows tonight will be mild in the lower to mid 50s,
with highs a bit warmer on Thursday, in the 60s to around 70.
The warmest readings will be across the interior Thursday.


A surface cold front will approach the area Thursday night and
weaken as it does so. Although there does seem to be some lift and
instability in association with the front, it is not impressive and
only a slight chance of showers and a passing thunderstorm is

Bermuda type high pressure will set up over the north central
Atlantic. This will bring in some warmth and humidity to the area.
Temperatures away from the coast will reach the upper 70s to lower
80s, while temperatures near the coast will remain in the lower to
middle 70s, with perhaps some upper 60s along the immediate coast.
Dew points will rise into the upper 50s to perhaps some lower 60s.

The next cold front approaches from the northwest Saturday and
pushes south of the area late in the day. This front looks to be a
bit stronger than the previous one, with some lift noted in the
middle and upper levels, but again, nothing too impressive. Most
unstable CAPE values however are in the 1000-2500 J/kg range, mainly
away from the coast, where conditions will be warmest. Lifted index
values of -3 to -5 noted in the 00Z GFS. So, showers and a passing
thunderstorm is once again possible Saturday. If further model runs
continue with these values, some strong to severe storms are
possible, but its too early right now.

High pressure builds in for Saturday night and Sunday, with the cold
front settling to our south. The front will then move back north as
a warm front Sunday night into Monday, with a return to unsettled
conditions starting Sunday. The warm front lifts north on Monday,
with the cold front quickly approaching and moving through Monday
night into Tuesday.


Low pressure approx 50 miles SSE KJFK will meander in the
vicinity before slowly shifting east this afternoon and evening.

Mostly IFR expected, however some prevailing or tempo MVFR cigs
expected mainly west of the Hudson River. SHRA becomes less
likely this afternoon.

NE winds around 10 KT becoming a little lighter this aftn.
Winds eventually bcmg light and variable this evening.

     NY Metro Enhanced Aviation Weather Support...

Detailed information, including hourly TAF wind component forecasts,
can be found at: http:/

KJFK TAF Comments: CHC cigs tempo 1000-1500 FT or prevailing a
couple hours this afternoon.

KLGA TAF Comments: CHC cigs tempo 1000-1500 FT or prevailing a
couple hours this afternoon.

KEWR TAF Comments: Timing of beginning/end of MVFR cigs may be
off by an hour or two.

The afternoon KEWR haze potential forecast is YELLOW...which implies
slant range visibility 4-6SM outside of cloud.

KTEB TAF Comments: Timing of beginning/end of MVFR cigs may be
off by an hour or two.

KHPN TAF Comments: Timing of beginning/end of MVFR cigs may be
off by an hour or two, or MVFR might be only tempo or not
happen at all.

KISP TAF Comments: Slight improvement in cigs might not occur or at
least may be off by an hour or two this afternoon.

.Thursday...IFR/LIFR potential to start...with gradual improvement
to VFR.
.Friday...Chance of MVFR in showers/thunderstorms.


Dense fog has developed across the eastern waters this morning.
This could potentially linger into the remainder of the day and
spread westward.

SCA for hazardous seas remains up on the ocean waters through
Thursday night due to an easterly swell as weakening low
pressure slowly lifts NE from the Delmarva this morning to the
New England coast on Thursday.

Waves remain above SCA criteria through Friday and much of Friday
night. Waves remain below 5 ft through Sunday night, though there
may be a brief period of 5 ft waves on the ocean as south to
southwesterly flow builds ahead of an approaching cold front.

Better chances of seeing SCA criteria on the ocean and back bays
Monday into Monday night as a stronger frontal system impacts the
region. Waves on the ocean build to 5 ft Monday, and up to 8 ft by
Monday night. Gusts of 25 to 30 kt are possible for the ocean and
back bays Monday into Monday night, diminishing late Monday


An additional tenth to quarter inch is possible across eastern
LI/SE CT this morning.

No significant rainfall expected in the long term. However, there
may be isolated brief heavy downpours in any thunderstorms that
develop during this time period.


Due to high astronomical tides and an easterly swell the next
couple of days, water levels may approach minor coastal flood
benchmarks, in particular across the south shore back bays of
western LI. Only 1/3 to 3/4 of a foot of surge is needed for
minor flooding. A coastal flood statement has been issued for
this evening`s high tide cycle for these locations.

In addition, the elevated water levels combined with a prolonged
period of 5-9 ft breaking surf tonight into Thu will result in
beach erosion issues and may cause some localized dune toe
erosion during the high tides.


MARINE...Small Craft Advisory for hazardous seas until 6 AM EDT Friday
     for ANZ350-353-355.
     Dense Fog Advisory until noon EDT today for ANZ330-340-350.


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