Area Forecast Discussion
Issued by NWS Upton, NY

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FXUS61 KOKX 270829
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
429 AM EDT Wed Mar 27 2024

.SYNOPSIS...
A frontal system approaches today and passes offshore early
Thursday. Low pressure develops along the front and tracks east
of the area Friday. A clipper type system passes to the south
and east late Saturday through early Sunday. Another low moves
through the Great Lakes region Monday and Tuesday as a warm
front approaches.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Stratus has overspread the area with the entire cwa ovc this
mrng. Lowest lvls are not saturated so not much fog. A few
pockets of lift came thru and produced -ra and dz overnight.
With cigs lowering thru the mrng hours and signs of more pockets
of omega in IR, will continue with chances for lgt rain and dz
thru 15Z.

An increase in mid lvl moisture, as well as lift around 7-12k
ft, could help to produce more pockets of rain this aftn. Time
heights suggest high based pcpn with evap cooling indicated by
llvl subsidence. As a result, only went with light rain chances
and kept out the dz. Did have to go abv NBM pops in this
scenario.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
A 150+ kt h2 jet provides upr divergence tngt. The response
should be moisture convergence and lift across the cwa based on
the position of the jet. As a result, the fcst is for periods
of rain and dz across the entire cwa and went well abv the NBM
pops for many areas.

Much of the same for the first part of Thu, then the nature of
the sys transitions as low pres begins to deepen over the Atlc.
Uncertainty with the modeling. The 00Z ECMWF is well E of the
benchmark with the low. The NAM, GEM, and GFS are left of the
track but still E of the benchmark. This favors ern areas for
getting into the rain shield on the wrn side of the low Thu aftn
and eve, and less rain elsewhere. Any further ewd trend could
relegate most of the pcpn to the ocean. NW winds lock in by
aftn, then gradually increase Thu ngt as they respond to the
falling pres. The low doesn`t really get going until Fri aftn
based on the progs, and by that time, it is expected to be 200
to 300 miles E of Montauk and pulling away. Stuck with drying
NBM pops from W to E Fri, with brisk winds Fri into Fri ngt.

NBM temps with local adjustments were used.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
No significant changes in the long term period and stuck fairly
close to previous forecast/NBM.

Dry weather is expected Saturday. A clipper type system is expected
to pass south and east of the region Saturday night into early
Sunday. With slightly above normal temperatures Saturday into Sunday
much of the area will have rain showers, with maybe a rain/snow mix
across the northern tier Saturday night.

Weak high pressure briefly builds into the area Sunday and
quickly weakens Sunday night. A near zonal flow will bring an
amplifying trough into the central US and Great Lake region
Monday into Tuesday as a warm front with the low slowly approaches
from the south. The NBM continues to show some likely probabilities
with the system for next week, but will continue to keep POPS capped
at chance with some uncertainties in the guidance with the timing of
the warm front, which may well be delayed with the low remaining
across the Great Lakes region.

NBM temperatures looked reasonable through the extended and
were used. Temperatures will mainly be near normal levels except
slightly above for Saturday and Sunday.

&&

.AVIATION /08Z WEDNESDAY THROUGH SUNDAY/...
A cold front slowly approaches on today.

MVFR/IFR conditions expected this morning. A light onshore
flow, will result in the possibility of mist, fog, and drizzle,
through the morning push. Can not rule out some localized sub
IFR possible right around daybreak, however confidence is low.
Gradual return to MVFR is expected mid to late morning, with
ceilings remaining near or under 3 kft into the afternoon.

Rain is expected to develop late this morning, and become more
steady across KSWF around 18z, eventually moving into all the
terminals after 00Z Thursday.

Light winds tonight generally under 5 kt may be a bit variable
in direction, but with an easterly component. Southerly flow
becomes more established this afternoon, though speeds remain
light.

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

Possible fog, mist, drizzle overnight until daybreak or so.

Timing of category changes may be off by several hours.

OUTLOOK FOR 06Z THURSDAY THROUGH SUNDAY...

Wednesday night: IFR or lower with rain.

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 kt.

Friday: MVFR early, becoming VFR in the afternoon. Slight chance
of rain 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. Gusts diminish at night.

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

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

&&

.MARINE...
A sca remains in effect on the ocean thru tngt, then seas around
4 ft on Thu. Winds increase Fri with a sca or mrgnl gale
possible Fri and Fri ngt. Conditions slowly improve across the
western waters during Saturday, and then the eastern waters
Saturday evening, as the low tracks through the Canadian
Maritimes, and high pressure builds to the west.

&&

.HYDROLOGY...
No hydrologic impacts are anticipated into early next week,
unless an unexpected shift occurs with the storm sys on Thu.

&&

.TIDES/COASTAL FLOODING...
The overnight guidance generally keeps all areas blw minor
flood thresholds today and tngt. The extreme high end of the
ensemble spread suggests a low prob to hit minor during the eve
high tide cycle for the usual spots on the South Shore. Due to
the low prob of occurrence and limited impacts if it does, an
advy/statement has not been issued attm.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory until 8 AM EDT Thursday for ANZ350-353-
     355.

&&

$$

SYNOPSIS...BC/JMC
NEAR TERM...JMC
SHORT TERM...JMC
LONG TERM...BC
AVIATION...BC
MARINE...BC/JMC
HYDROLOGY...BC/JMC
TIDES/COASTAL FLOODING...JMC


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