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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KOKX 230534
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
134 AM EDT Tue Apr 23 2024

.SYNOPSIS...
Weak high pressure builds across the area overnight and then
offshore on Tuesday as a frontal system approaches from the
Great Lakes. A surface trough followed by a cold front moves
through Wednesday. Behind the frontal passage, high pressure
builds into the region Wednesday night and Thursday, shifting
offshore on Friday. A warm front may lift through the area this
weekend and the associated frontal system may linger nearby into
early next week.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Weak high pressure builds across the area overnight with winds
becoming light and variable. Thus, continuing current Frost/Freeze
headlines for most of the interior as well as SE coastal CT and
eastern LI. Orange county NY is the one zone under a Freeze
Warning as the western half of the county should get to or just
below freezing. Lows are forecast to range from the lower and
mid 30s inland/Pine Barrens of eastern LI/SE Coastal CT, around
40 for much of the coast, and the lower to mid 40s NYC/NJ metro.

During Tuesday, high pressure shifts offshore early as a frontal
system approaches from the Great Lakes. A return flow gets
established quickly with the winds primarily off the colder
ocean and out of the S and SSE. This wind direction should
result in a fairly wide temperature spread across the region
for the afternoon as areas further west and inland won`t be
as influenced by the marine air. Went a few degrees warmer than
NBM for temps across western third of the area and into far
northern CT zones, with some manual adjustments based on climo
for this time of year further east.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM WEDNESDAY/...
-- Changed Discussion --
For Tuesday night with the high getting further east and the
approach of the next system from the west look for the winds to
veer more to the S and perhaps the SSW towards Wed AM. The
column will undergo more of a deep layered SW flow. Thus, clouds
will increase, especially above 5 kft or thereabouts. A lot
will depend on the speed and the timing of the approach of the
frontal boundary, but the column may moisten enough that some
light showers or sprinkles could very well break out before
daybreak Wed, especially across western most locations. Went
slight chance to chance PoPs during the pre-dawn hours towards
sunrise.

For Wednesday the pre-frontal trough pushes through resulting
in widespread shower activity, with the higher PoPs across
mainly northern sections for the morning and for the early
portion of the afternoon. The winds will become more SW for the
first half of the day, then become due W and eventually NW
during the afternoon as drier air wraps in quickly, especially
at the lower levels. The NAM3km indicates some CAPE in the 5 to
15-20 kft level, but this may be overdone as the HRWFV3 has
virtually no CAPE. For now kept out any chance of thunder with
chances appearing too low as the column will likely be dry
enough to preclude any meaningful convection. The sun should
start to break through with a strato-cumulus deck for the later
in the afternoon as a W to NW breeze develops. Only looking for
up to a tenth of an inch or so of rain with PWATs not even
getting to an inch on most guidance. Temperatures will get into
the 60s with good mixing later in the afternoon and likely some
breaks of sun. A few spots inland could get into the lower 70s
if the system moves to the east faster than progged which would
result in a longer period of at least partial sunshine in the
afternoon.
-- End Changed Discussion --

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
-- Changed Discussion --
The region dries out Wednesday night behind the fropa as the
trough axis shifts east and surface high pressure builds in from
the Great Lakes. The high remains over the region Thursday,
before slipping offshore Friday and setting up southerly flow.
Meanwhile, ridging gradually amplifies and builds over the East
Coast through the remainder of the week. Into the weekend, a
shortwave over the Central US will attempt to ride up and over
the amplified ridge and may send an associated warm front
through Sat night or Sunday, but precipitation appears limited
as the surface low passes well to the north and west. Forecast
confidence lowers after this point with diverging solutions, but
lots of time to fine tune.

Temperatures average near, to just below, normal for late
April. The coolest day looks to be Thursday, with northerly flow
helping to lower H85 temps to as low as -3C. This should
translate to afternoon highs in the 50s across the region, or
about 10 degrees below normal. In addition, frost/freeze
headlines will likely be needed Wed and Thu night, at least for
portions of the local area as temperatures outside the urban
metro fall into the 30s. Only slight moderation Fri/Sat, before
the warm front attempts to lift through, and the resultant SW
flow should warm the air mass into the 70s, particularly west of
the Hudson and away from maritime influence. With only subtle
adjustments, stayed closed to national blended guidance for this
update.
-- End Changed Discussion --

&&

.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
-- Changed Discussion --
Weak high pressure builds across the area overnight and then
offshore on Tuesday as a frontal system approaches from the
Great Lakes.

VFR.

Winds generally light and variable to a light SW flow
overnight, then becoming southerly with winds increasing. Gusts
develop late morning, and more likely during the afternoon,
less than 10kt. Southerly flow gradually weakens at night.


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

Gusts on Tuesday may be more occasional and late in the
afternoon.

OUTLOOK FOR 06Z WEDNESDAY THROUGH SATURDAY...

Late Tuesday night: VFR. A chance of showers late, mainly at
the NYC metro terminals, and northwest, eastern terminals toward
morning.

Wednesday: VFR, with a chance of MVFR in showers, mainly in the
morning. SW winds 10-15G15-25kt, becoming W-NW in the
afternoon, then northerly at night 5 to 10kt.

Thursday-Friday: VFR.

Saturday: Mainly VFR. Chance of showers. S winds G15-20kt.

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

&&

.MARINE...
Primarily 2 ft ocean seas prevail through tonight with high pressure
in control and a relatively weak pressure gradient overall. Sub
small craft conditions will prevail across the coastal waters
through at least the first half of Tuesday, followed by small
craft conditions becoming more likely later in the afternoon and
evening for the Harbor and the western half of the ocean as a
hybrid Ambrose jet induced wind attempts to develop. The
prevailing southerly flow should result in small craft
conditions developing further east on the ocean later Tuesday
night and into Wednesday as ocean seas increase primarily to 5
to 6 ft. Ocean seas gradually subside late Wednesday night with
weakening NW flow, falling below advisory levels by Thursday
morning. Winds and seas then remain below advisory levels on all
forecast waters into the start of the weekend.

&&

.HYDROLOGY...
No hydrologic concerns attm.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
CT...Frost Advisory until 8 AM EDT this morning for CTZ005>008-011-
     012.
NY...Frost Advisory until 8 AM EDT this morning for NYZ068>070-079-
     081.
     Freeze Warning until 8 AM EDT this morning for NYZ067.
NJ...Frost Advisory until 8 AM EDT this morning for NJZ002.
MARINE...Small Craft Advisory from 4 PM this afternoon to midnight EDT
     tonight for ANZ338.
     Small Craft Advisory from 5 AM to 6 PM EDT Wednesday for
     ANZ350.
     Small Craft Advisory from midnight tonight to 6 PM EDT
     Wednesday for ANZ353.
     Small Craft Advisory from 6 PM this evening to 6 PM EDT
     Wednesday for ANZ355.
-- End Changed Discussion --

&&

$$

SYNOPSIS...JE/DR/DW
NEAR TERM...JE/DR/DW
SHORT TERM...JE
LONG TERM...DR
AVIATION...MET
MARINE...JE/DR
HYDROLOGY...JE/DR