Area Forecast Discussion
Issued by NWS Upton, NY

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463
FXUS61 KOKX 061049
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
649 AM EDT Mon May 6 2024

.SYNOPSIS...
High pressure off Nova Scotia shifts farther out into the Atlantic
today as a cold front approaches the region from the west, passing
through tonight. Behind it, weak high pressure briefly returns on
Tuesday, before the front returns as a warm front Wednesday. A
series of low pressure centers then impact the weather through
Friday, and possibly into the weekend as well.

&&

.NEAR TERM /THROUGH TONIGHT/...
In the wake of last night`s rain, areas of fog have developed
in parts of the region early this morning with weak flow and
residual moisture, primarily across NE NJ, but eastward into
southern CT and LI as well. While vsbys have largely remained
above a quarter mile, locally dense fog remains possible for the
next couple of hours and motorists should remain vigilant for
quick changing conditions. Otherwise, the rain has tapered
almost regionwide as the shortwave passes east, and the forecast
remains on track.

Ridging and surface high pressure that was in place over the
weekend has shifted well out into the Atlantic as a shortwave
tracks through the Northeast and offshore as well. Meanwhile, a
closed upper low swings into eastern Canada and will help send a
cold front through the region tonight.

Temperatures jump 10 to 20 degrees compared to Sunday with
ongoing WAA in the resulting SW flow, likely rebounding into
the low to mid 70s away from the coast. Should more breaks in
the cloud cover develop, temperatures inland could achieve mid
to upper 70s.

Can`t rule out a few pop up showers in the afternoon, mainly
across the interior, ahead of the trailing cold front, but
coverage appears limited on CAMs at this point with weak lift
and moisture. Maintained a low chance of a thunderstorm as well,
but likely isolated at best. The front moves through tonight,
and the flow veers NW as a result, bringing in drier air and
decreasing cloud cover overnight.

&&

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
Weak surface high pressure builds in from the Great Lakes behind
the fropa on Tuesday. This should set up the clearest day of the
week so far, with drier air working down in the northerly flow.
A mild afternoon for most with downsloping helping the interior
and areas away from the coast to warm into the mid to upper
70s. Lower 80s possible in the urban metro of NE NJ. Much more
sky than clouds should be apparent and sunshine prevails much of
the day.

Thereafter, the front that pushed through Monday night stalls
over the Mid Atlantic on Tuesday in zonal flow, returning to the
region Tuesday night as a warm front as the high erodes and low
pressure tracks into the Great Lakes. This will reintroduce
rain chances by Wed AM, and perhaps some thunderstorms into
Wednesday afternoon. Still a bit too far for our CAM coverage,
so timing and coverage will need to be refined over the next day
or two. SPC currently has the region outlined in a general
thunder risk.

Wednesday is likely the hottest day of the week for at least
portions of the area as the warm front attempts to lift north.
Exceptions may be eastern LI and southern CT, where onshore
southerly flow will limit temperatures. Elsewhere, low 80s
possible, with mid 80s into NE NJ. The attendant cold front
passes through Wednesday night as the low exits to our east, but
the pattern remains unsettled into late week as a wave of low
pressure along the boundary to the south approaches thereafter.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
Low pressure approaches from the Ohio Valley on Thursday with a
secondary low center forming and passing over us or just off to our
south Thursday night. As energy continues to transfer from the
parent low to the secondary low center, a lingering trough between
the two centers remains near the forecast area during Friday. Rain
is likely Thursday and Thursday night, with still some chances of
showers during Friday with moisture convergence along the trough
along with some shortwave lift from aloft. An isolated rumble of
thunder can`t be ruled out mainly Thursday afternoon and evening as
elevated instability will be present.

There`s some uncertainty regarding the weekend, but overall there
seems to be a model trend over the past day or two toward drier
conditions. Although both days currently feature a chance of showers
in the forecast, it can very well end up dry all weekend. There are
indications of deep weak ridging for Saturday, then an area of low
pressure that may pass too far to our south and west on Sunday to
bring showers.

NBM was used for temperatures through the long term period. Cooler
than normal through Saturday with a return toward more seasonable
temperatures on Sunday.

&&

.AVIATION /12Z MONDAY THROUGH FRIDAY/...
A cold front slowly approaches from the west, passing through
tonight.

IFR or lower through the morning push, improving to low-end
MVFR this afternoon for some terminals. IFR/MVFR this evening
improves to VFR late tonight. Iso TSRA late aftn/early evening,
but not enough probability and coverage to mention in TAFs.

Light and variable winds through the morning push, possibly
favoring NE to N the most. Winds shift more SW-W for the
afternoon, but remaining under 10kt. Light N winds for late
tonight.

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

Amendments likely due to timing of the changing of flight
categories.

OUTLOOK FOR 06Z TUESDAY THROUGH FRIDAY...

Monday night: Improving to VFR.

Tuesday: VFR, becoming MVFR to IFR late at night with showers likely.

Wednesday: MVFR or lower AM, improving to VFR PM. Chance of showers.
Thunderstorms possible mainly in the afternoon.

Thursday: MVFR/IFR. Showers likely, mainly in the afternoon and
night with an isolated TSTM possible.

Friday: MVFR/VFR with showers possible.

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

&&

.MARINE...
Areas of fog have developed on the waters early this morning,
and may be dense at times. Marine Dense Fog Advisory has been
hoisted thru 13Z this morning for the LI Sound west of New
Haven, the NY Harbor, South Shore Bays, and ocean waters
between Sandy Hook and Moriches Inlet. Visibilities may drop
below 1 nm before gradual improvement is expected late morning.

Winds and seas are expected to remain below SCA conditions through
Wednesday.

Easterly winds increase on Thursday, and this onshore flow combined
with swell being generated from low pressure passing nearby is
expected to build ocean seas to advisory levels starting late
Thursday night into Friday morning, and lasting well into Friday
night.

&&

.HYDROLOGY...
There are currently no hydrologic concerns through this week.

&&

.TIDES/COASTAL FLOODING...
Astronomical tides are running high with the approach of a new
moon Tuesday night.

A statement has been issued for localized minor flooding with
tonight`s high tide cycle for Southern Fairfield County and the
south shore back bays of Nassau County.

A more widespread minor flooding event that would necessitate
advisories for these two locations plus Southern Queens will more
likely occur with the nighttime cycles from Tuesday night through
at least Thursday night. Statements for these 3 high tide cycles
may be needed for other parts along western LI Sound, SW Suffolk
County, as well as lower NY Harbor and Brooklyn.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Dense Fog Advisory until 9 AM EDT this morning for ANZ335-338-
     345-353-355.

&&

$$

SYNOPSIS...JC/DR
NEAR TERM...DR
SHORT TERM...DR
LONG TERM...JC
AVIATION...JC
MARINE...JC/DR
HYDROLOGY...JC/DR
TIDES/COASTAL FLOODING...JC