564
FXUS61 KOKX 050849
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
349 AM EST Wed Feb 5 2025

.SYNOPSIS...
High pressure builds over the area through this evening. A
low pressure system then impacts the area late tonight into
Thursday. High pressure then builds into the area through the
end of the week. High pressure over the area Saturday moves
offshore followed by a low pressure for Saturday night into
Sunday. High pressure builds back in for the beginning of the
week followed by a series of low pressure systems for the middle
of the week.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Fast zonal flow aloft will send a PAC shortwave towards the
region through tonight. High pressure will continue to build
over the area today ahead of the shortwave. There will be
varying levels of mid and upper level moisture through the day
with eastern Long Island and southeast Connecticut having the
higher chance of remaining mostly clear to partly cloudy. Strong
subsidence leads to dry low levels with temperatures topping
out below normal in the lower and middle 30s.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
Main concern for tonight into Thursday will be a wintry mix
and impacts to the Thursday morning commute.

Broad low pressure moves over the Great Lakes tonight with
its associated warm front lifting towards the area from the
southwest. Warm advection increases tonight, especially after
midnight, which will moisten the column and provide strong lift
to develop precip after 3 am west and continue overspreading
the area through day break. This will be a quick moving system
with the bulk of the precip occurring Thursday morning and
beginning to taper off from west to east in the afternoon.

Thermal profiles are cold enough to support snow at the onset.
Warming aloft is still expected bringing a wintry mix Thursday
morning as secondary low pressure likely develops just south of
Long Island. Initially the low level cold air looks deep enough
to change the precip to sleet or a mix of snow/sleet. The low
level cold air shrinks as warmer air advects in under a
strengthening S-SE flow which will then introduce some freezing
rain, which likely spreads north and east late morning. Plain
rain is expected for much of the area except for the interior
where freezing rain may persist into the early afternoon,
depending on how quickly the surface cold can scour out. The
intensity of the precip should drop off in the afternoon as the
deeper moisture and lift push east of the area. Much of the
precip should largely be over by the Thursday evening commute.

Temperatures are a bit more challenging across the NYC metro,
western Long Island, and coastal CT in the morning. The guidance
can struggle with these situations on top of the fact the
surface pattern is not favored for an all snow event. Surface
temperatures will be rising in the morning, but with wet bulbing
at the onset and temps beginning in the upper 20s, it may take
some time to fully rise above freezing. The warming aloft and
surface temperature concerns introduces a chance for a few hours
of freezing rain or freezing rain mixed with some sleet for
portions of the NYC metro, western Long Island, and coastal CT.
Have decided to expand the Winter Weather Advisory to include
these locations due the potential of a light glaze of ice.
Snowfall amounts are not at criteria, but there will likely be
travel impacts given the event is occurring during the morning
commute. These conditions are enough to support the expansion of
the Advisory. Temperatures should be well above freezing by
late morning, so will let the Advisory end at 11 am. No changes
were made to the rest of the Advisory.

Snow and sleet accumulations are similar to the previous
forecast with a slight adjustment upward across Southern CT
where profiles remain coldest the longest. Around 2 inches of
snow/sleet forecast across S CT with 1-2 inches across the Lower
Hudson Valley and interior NE NJ down into the northern half of
the NYC metro. For the southern half of the NYC metro and Long
Island, generally around an inch expected. Snow amounts could be
slightly higher if the warm air aloft is slower to move over
the region. Up to a tenth of an inch of ice expected across much
of the interior.

Dry conditions expected Thursday night, but the trailing cold
front likely does not move through until early Friday morning.
High pressure then builds on Friday with a gusty NW flow in
place over the area. Gusts may peak around 40 mph, but think
winds stay below Advisory levels at this time. Highs on Friday
look to be just above normal as the colder air will take some
time to reach the area, similar to what just occurred on
Tuesday. The high then settles over the area Friday night, but
the fast zonal flow aloft continues with clouds likely
increasing at night ahead of the next system.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
High pressure over the area on Saturday will gradually shift
offshore as a strengthening surface low pressure system
approaches from the west. Models are in fairly good agreement
on the low tracking generally over the area as it intensifies,
allowing for a widespread shield of moderate precipitation to
overspread the region Saturday night and through Sunday morning.
Temperatures ahead of the low are expected to be in the middle
to upper 30s along the coast with sub-freezing temperatures
inland. This will likely result in initial widespread snowfall
for much of the area. As temperatures fall a bit from wet-
bulbing and a reduction in solar heating overnight, snowfall
should continue, but as the center of the low tracks generally
overhead, warm air aloft may intrude on the CWA. This allows for
the possibility of precipitation transitioning from a primarily
snow to a mix of snow, sleet, and freezing rain or plain rain.
Temperatures should slowly warm late in the night such that much
of the area ends with a plain rain with a rain/snow mix for
northernmost areas.

The low departs late Sunday with high pressure building in behind
it. A brisk NW flow will usher in another cold airmass for the
beginning of the week with highs generally in the middle 30s. Global
models are then fairly consistent on a series of frontal waves
developing and traversing south of the area early Tuesday through
late Wednesday. The proximity of these systems will determine how
much precipitation we receive, but being on the northern fringe of
these system would promote primarily snow, though there remains
ample uncertainty in the intensity, track, and moisture content of
these systems.

&&

.AVIATION /09Z WEDNESDAY THROUGH SUNDAY/...
High pressure builds overnight and settles over the area on
Wednesday. Low pressure approaches from the west late tonight
and Thursday morning.

VFR through late tonight.

NW winds around 10kt through the AM push. Winds remain around
10 kt as they become more northerly during the day. Winds may
go light and variable at night before shifting out of the E/SE
at 5-10kt late tonight ahead of an approaching low pressure.

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

Occasional gusts are possible for a few hours towards towards
midday.

.OUTLOOK FOR 09Z THURSDAY THROUGH SUNDAY...

Wednesday night: VFR initially, MVFR or lower cond in light snow
developing before daybreak.

Thursday: MVFR or lower cond with light snow/sleet to start.
Precip should change to rain after about 14Z-15Z at the NYC metros
and KISP, by about 17Z at KBDR/KGON, and could transition to
freezing rain at KSWF mid to late morning before changing to rain by
18Z. Snowfall amounts should be light, mainly either side of an inch.

Thursday night: Rain ending with cond becoming VFR.

Friday: VFR. W winds G20-25kt.

Saturday: Chance of snow with IFR cond in the afternoon. Snow
changing to a wintry mix expected at night.

Sunday: Precip should change over to all rain by daybreak Sunday
except for KSWF. MVFR to IFR at times. Becoming VFR as precip ends
during Sunday afternoon.

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

&&

.MARINE...
A weak pressure gradient today into tonight will lead to winds
and seas below SCA levels. The next chance of SCA conds will be
on Thursday, and mainly on the ocean waters as low impacts the
waters. Winds should weaken Thursday night, but elevated seas
may remain on the ocean. Strong NW flow is expected Friday with
SCA conditions on all waters. Think winds stay below gales at
this time. Conditions should improve Friday night as the next
high pressure builds over the waters.

Sub-SCA conditions expected on Saturday with high pressure
overhead. Wind and waves increase Saturday night and Sunday
morning with SCA conditions on the ocean. Winds may result in
SCA conditions for the sheltered waters as well but remain
marginal at this time. Slight chance of gales on the ocean water
Sunday depending on how close the strengthening low tracks.

&&

.HYDROLOGY...
There are no hydrologic concerns through the forecast period.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...Winter Weather Advisory from 4 AM to 1 PM EST Thursday for
     CTZ005>012.
NY...Winter Weather Advisory from 4 AM to 1 PM EST Thursday for
     NYZ067>071.
     Winter Weather Advisory from 4 AM to 11 AM EST Thursday for
     NYZ072>075-078-080-176>179.
NJ...Winter Weather Advisory from 4 AM to 1 PM EST Thursday for
     NJZ002-004-103>105-107.
     Winter Weather Advisory from 4 AM to 11 AM EST Thursday for
     NJZ006-106-108.
MARINE...None.

&&

$$

SYNOPSIS...DS/MW
NEAR TERM...DS
SHORT TERM...DS
LONG TERM...MW
AVIATION...MW
MARINE...DS/MW
HYDROLOGY...DS/MW