Area Forecast Discussion
Issued by NWS Upton, NY

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FXUS61 KOKX 261827
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
227 PM EDT Tue Mar 26 2024

.SYNOPSIS...
A high pressure ridge over the area will gradually weaken
through tonight. A cold front approaches on Wednesday and
slowly passes through during Wednesday night into Thursday.
Meanwhile, low pressure develops along the Atlantic seaboard,
tracks NE, passing us to the southeast late Thursday night into
Friday morning. The low eventually tracks into the Canadian
Maritimes over the weekend. Another low pressure system may
impact the area early next week.

&&

.NEAR TERM /THROUGH WEDNESDAY/...
The forecast is mainly on track. Minor adjustments were made to
hourly temperatures and dewpoints based on the latest trends
with temperatures having to be raised.

Shallow moisture trapped under an inversion keeps us cloudy today.
Weak isentropic lift arriving from the east introduces a slight
chance of light rain or drizzle over LI and southern CT
this morning. Chances of light rain and drizzle then expand
west this afternoon with the help of some isentropic lift. High
temperatures about 5 degrees below normal.

&&

.SHORT TERM /WEDNESDAY NIGHT THROUGH THURSDAY NIGHT/...
Light rain and drizzle potential expands farther to the rest of the
area tonight. Moisture then deepens west to east on Wednesday ahead
of a cold front. Threat of rain therefore trends higher towards the
western zones. Also expecting areas of fog starting tonight when the
turbulent mixing potential near the bottom of the low level
inversion lessens. We could be stuck with the fog well into the day
Wednesday with light winds and plenty of low level moisture. Milder
for Wednesday, with highs in the 50s.

A cold front enters the forecast area Wednesday night, bringing an
area of focused moisture convergence with it. Rain is therefore
likely Wednesday night with the deeper moisture and lift along the
front. Models show elevated CAPE Wednesday afternoon and night, but
lift appears to be to weak for a mention of thunder.

The front slows its eastward motion on Thursday as the flow aloft
amplifies and a 500mb trough axis approaches. This will help focus
energy along an elongated area of low pressure toward the Carolina
coast. This deepening low center then tracks NE and approaches not
too far SE of the 40N/70W benchmark late Thursday night. The
combination of the front, frontogenetic forcing on the NW side of
the elongated low, and synoptic upper divergence from a jet streak
continue the likelihood of rain across the area on Thursday, with
rain chances diminishing west to east Thursday night. Cold air wraps
in from the NW as the rain is ending late, but likely too late for
any potential snow (northernmost zones only) to be of any
significance. Will keep out the mention of snow for the time
being.

&&

.LONG TERM /FRIDAY THROUGH TUESDAY/...
Low pressure passes east of the region on Friday, as a cold front
slides east of the region. Any left over precipitation Friday
morning is expected to come to an end shortly after daybreak, mainly
across the eastern sections of Long Island and Connecticut. There is
a low end chance that POPs linger into Friday afternoon. There is
some uncertainty with just how strong the low is that passes east of
the area and its exact placement on Friday. The deeper the low is,
the better chance that we could see some snow showers on the back
end of the precipitation Friday morning. Will go with a rain/snow
mix for now. Otherwise, expect a gusty northwest flow, with a
colder/drier airmass working into the region.

Conditions are expected to remain dry at least Friday night and the
first half of Saturday. Some of the forecast guidance is hinting at
a quick moving low pressure system/upper level shortwave to
pass over the area late Saturday into Sunday. This may set off a
few showers/light rain, however the timing and placement of
this feature remains a bit uncertain with low confidence. Will
only carry slight chance POPs for now.

The next chance of rain comes Monday night into Tuesday as yet
another low pressure treks towards the region. With this being a day
7-8 event, will cap POPs at 50 for now.

&&

.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
High pressure over the region slowly weakens through tonight. A
cold front approaches on Wednesday.

MVFR stratus expected this afternoon followed by IFR stratus
tonight into early Wednesday. Fog is also expected to develop
late tonight and last into Wednesday morning with visibilities
down to MVFR to IFR. Localized sub-IFR can be expected early
Wednesday. The forecast has some improvement to MVFR late
Wednesday morning into Wednesday afternoon but the timing of
this is uncertain. Also, there is forecast drizzle and light
rain but chances are low so only have a part of late tonight
mentioning this.

Winds will be generally E-NE near 10 kt this afternoon into
this evening, but a little higher for KISP and KGON more in the
10-15 kt range. Gusts expected for KGON near 20-25 kt but more
occasional farther west. Winds tonight into Wednesday are
forecast to be near 5 kts but variable at times for direction
with otherwise a general easterly direction.

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

Timing of MVFR to IFR or lower may be off by 1 to 3 hours.

OUTLOOK FOR 18Z WEDNESDAY THROUGH SUNDAY...

Wednesday: IFR improving to MVFR. Higher chances of rain mid
afternoon into evening, becomes likely for KSWF. Rain becomes
likely for most terminals at night.

Thursday: IFR with rain, eventually tapering off late at night
except at KGON. Improvement to MVFR at night. NW wind gusts
Thursday night to near 20-25 kt.

Friday: MVFR early, becoming VFR in the afternoon. Slight chance
of rain or snow showers early for KISP and KGON. NW wind gusts
20-25 kt.

Saturday: Mainly VFR during the day. Chance of showers and MVFR
at night, possibly mixed with snow for KSWF. W-NW wind gusts
20-25 kt day into early evening.

Sunday: Mainly VFR. NW wind gusts 15-20 kt in afternoon.

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

&&

.MARINE...
SCA remain in place on the ocean through Weds afternoon due
mainly to elevated seas from a lingering swell. Gusts to at
least 25kt also expected during the day today, but becoming less
likely heading into the evening. SCA also for eastern LI sound
through this afternoon - again primarily for elevated wave
heights. A prolonged period of winds at or below 10kt is
expected from late tonight through Thursday morning. Winds then
increase Thurs afternoon and night from the N-NW as the pressure
gradient tightens over the waters. Advisory level gusts
expected at for all waters by the end of this period. Could get
close to gales on the ocean late Thursday night.

Low pressure passing east of the waters on Friday will result
in at least small craft conditions with both gusty winds and
elevated seas. There is a chance gales will be needed during the
daytime Friday. The small craft conditions are likely to
continue through the first half of the weekend before conditions
subside below SCA levels.

&&

.HYDROLOGY...
Mostly 1-2 inches of rainfall is forecast from Wednesday through
Thursday night. The higher amounts will be focused more toward Long
Island and southern Connecticut. Given the current flash flood
guidance, not anticipating hydrologic impacts, but if the
expected totals ramp up in subsequent forecasts, maybe some
minor flooding could occur over southern Connecticut.

No hydrologic impacts are anticipated for the weekend and into
early next week.

&&

.TIDES/COASTAL FLOODING...
One more round of minor flooding is likely this evening per latest
bias corrected surge guidance. Have issued advisories for tonight`s
high tide cycles for S Nassau and S Fairfield/Westchester, where
water levels will be at least a couple of tenths of a foot above
minor thresholds, with inundation up to 1/2 ft AGL. Also issued a
statement for most of the NY/NJ harbor area where water levels may
touch minor thresholds in spots, especially along Newark Bay and in
the NJ Meadowlands near the tidal Hackensack River.

Guidance may be took quick to lower surge thereafter, and may have
to watch the Wed night high tide cycle for one more high tide cycle
with water levels touching minor thresholds along parts of the S
Fairfield coast after midnight.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...Coastal Flood Advisory until 3 PM EDT this afternoon for
     CTZ009.
NY...Coastal Flood Advisory until 3 PM EDT this afternoon for
     NYZ071-073-176-177.
NJ...None.
MARINE...Small Craft Advisory until 6 PM EDT this evening for ANZ332.
     Small Craft Advisory until 6 PM EDT Wednesday for ANZ350-353-
     355.

&&

$$

SYNOPSIS...BC/JC
NEAR TERM...JC/BR
SHORT TERM...JC
LONG TERM...BC
AVIATION...JM
MARINE...BC/JC
HYDROLOGY...BC/JC
TIDES/COASTAL FLOODING...BG


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