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000
FXUS61 KOKX 060902
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
502 AM EDT Thu May 6 2021

.SYNOPSIS...
High pressure builds through today. The high will slide east
tonight into Friday. A low pressure trough will move slowly
across Friday night into Saturday. A warm front along with an
associated low pressure area will approach the region on Sunday
into Sunday night. The low and front move east of the region
Monday into Monday night. High pressure will then gradually
build in from the west going into the middle of next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
A nw flow continues today, but will begin to relax this afternoon
into early this evening as the pressure gradient decreases. A good
deal of sunshine is expected through today, with temps likely to be
just a few degrees below normal. For tonight with weak high pressure
nearby skies will start off mostly clear, but some higher levels
clouds begin to work in later at night. With a light wind out of the
north and northeast temperatures will be allowed to cool, especially
during the first half of the night before any higher and mid level
clouds could have an impact on temps. Lows will settle right around
seasonable levels in urban locations, and a bit cooler in rural
locations with some degree of radiational cooling.

&&

.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
The upper level trough which progresses through the Eastern CONUS
will amplify slightly and begin to go more negative tilt later
Friday into Friday night. Low pressure will start to develop off the
SE US coast on Friday. The low should get better organized once it
gets further offshore into Friday night and Saturday. This should
prevent the region from seeing impacts from the offshore low as the
the upper level trough should progress enough to the east as to
prevent the low from taking a track closer to the coast.

On Friday expect temperatures once again to be a few degrees below
normal despite some sunshine. A developing onshore flow should keep
temperatures a touch cool, especially further east. For now tried to
be more optimistic with respect to cloud cover and strayed away from
the NBM cloud cover and went more optimistic. By later in the day
and into Friday night as a low pressure trough develops over the
area more clouds are anticipated. The majority of the forecast
guidance keeps the majority of the region dry through Friday night,
with perhaps far western areas getting into the leading edge of some
showers which are progged to edge their way towards the area from
the west in response to a norlun type trough and upper level
forcing. Temperatures once again Friday night will average close to
seasonable norms. The current thinking has slight chance POPs for
late Friday night east of NYC, and chance POPs west of NYC. The
trough axis is then expected to swing through into Saturday. For
now, thought it prudent to go with chance POPs across the entire
area, with higher end chance POPs further west during Saturday
morning.

The upper level trough axis pivots through by late Saturday
afternoon. This will bring any chance of showers to an end by
evening and maybe by late in the day. Any precipitation for early in
the weekend is expected to be light. Skies will then clear into
Saturday night. Temperatures should average below normal on Saturday
with a good deal of clouds with the upper level low swinging through
and a light northerly flow to start. A west to northwest flow
Saturday night will reinforce the cool conditions as temperatures
will average a good 5 to 7 degrees below average.

&&

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
There will be SW flow increasing on Sunday with dry conditions in
place initially as high pressure will be offshore in the Atlantic.
Highs forecast are in the upper 50s to mid 60s, a few degrees below
normal. Expecting an increase in clouds during the day as high
pressure moves farther out to sea and a warm front approaches from
the west.

This warm front approaches near the region along with its associated
low pressure center Sunday night into Monday. Isentropic lift and
warm air advection in the low levels will allow for the development
of overrunning stratiform rain Sunday night into Monday. Lows Sunday
night will be ranging from the lower 40s to lower 50s and highs for
Monday will only range from the upper 50s to lower 60s.

Rain ends Monday night as the front and low move east of the region
and out into the Atlantic. Lows for Monday night will be a few
degrees cooler than those of the previous night with some cold air
advection developing on increasing NW flow.

Skies will begin to clear as high pressure builds in from the Great
Lakes. Northwest flow will introduce some weak CAA, helping keeping
our temperatures a few degrees below normal both Tuesday and
Wednesday. Conditions look to remain dry into midweek.

&&

.AVIATION /09Z THURSDAY THROUGH MONDAY/...
High pressure will gradually build in through the TAF period.

VFR conditions are forecast. Main issue will be gusty winds
from the NW, mainly to the right of 310 degrees magnetic. Gusts
between 15 and 20 kt at times into early this morning will be
followed by more frequent gusts mid to late this morning around
20-24 kt. Winds will lower this afternoon with gusts more in
the 16-20 kt range. Winds diminish tonight.


 ...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...

The timing of wind gusts could be a few hours off in the TAF.
The gusts may very well be less frequent and not occur each
hour.

.OUTLOOK FOR 09Z FRIDAY THROUGH MONDAY...
.Late tonight...VFR. Diminishing NW winds.
.Friday...VFR.
.Friday night through Saturday...Periods of MVFR or lower
possible at times with rain shower chances.
.Sunday...Mainly VFR. W-SW wind gusts 15-20 kt on Sunday. MVFR
to IFR possible at night with rain becoming likely.
.Monday...MVFR to IFR with chances of rain.

Detailed information, including hourly TAF wind component
forecasts, can be found at: http:/www.weather.gov/zny/n90

&&

.MARINE...
Small craft conditions are expected through about midday or so
across the coastal waters. The pressure gradient will begin to relax
during this afternoon resulting in sub SCA conditions returning.
More tranquil conditions will follow for tonight and into early on
Friday. An easterly flow will increase later Friday afternoon into
Friday evening across the eastern most waters, but conditions should
remain below SCA criteria through the first half of the weekend.

Sub-SCA conditions are expected Sunday through much of Monday. Late
Monday afternoon through Monday night, is when SCA conditions are
forecast, mainly in terms of seas on the ocean. Wind gusts will be
marginal for SCA for parts of the eastern ocean which could reach 25
kt at times late Sunday afternoon into Sunday evening. Non-ocean
waters will be below SCA criteria Sunday through Monday night.

SCA potential lingers into Tuesday for ocean waters as the pressure
gradient tightens between the departing low and building high. Non-
ocean waters are expected to remain below SCA criteria.

&&

.HYDROLOGY...
No significant widespread rainfall is forecast at this time.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory until 2 PM EDT this afternoon for ANZ331-
     332-335-338-340-345-350-353-355.

&&

$$
SYNOPSIS...JE/JM
NEAR TERM...JE
SHORT TERM...JE
LONG TERM...JM/DR
AVIATION...JM
MARINE...JE/JM/DR
HYDROLOGY...JE/JM