975
FXUS61 KOKX 311011
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
511 AM EST Fri Jan 31 2025

.SYNOPSIS...
An approaching frontal system will impact the area through
tonight. Strong high pressure will then build down from Ontario
and the upper Great Lakes into New York and New England on
Saturday, then pass east of New England on Sunday. Low pressure
approaching from south central Canada Sunday night will then
move into Southeast Canada Monday into Monday night, followed by
high pressure through early Wednesday. This high will then
move offshore, with another frontal system eventually moving in
toward the end of the week.

&&

.NEAR TERM /THROUGH TONIGHT/...
Initial bands of precip moving into northern NJ and the NYC
metro attm. Obs at KMMU/KCDW showed sleet at the onset but think
this will change over to either rain or freezing rain as the
column saturates, sfc temps remain cold, and temps aloft remain
above freezing. Added E Passaic and W Bergen to the winter wx
advy with precip moving in and temps at or just below freezing.
Temps should slowly warm this morning, changing any freezing
rain over to plain rain except perhaps in parts of Orange
County, so the advy there may eventually need to be extended
there until midday. Still looking at trace amts to a couple
hundredths of an inch accretion.

There could be a lull in precip later this morning as this
first band lifts north and weakens, before steadier rain arrives
during the afternoon and continues into tonight as a warm front
nears Long Island and low pressure to the west moves over the
area. High temps should reach the upper 30s/lower 40s.

Precipitation gradually tapers off tonight as the low departs.
As precip ends, there may be just enough cold air for some light
snowflakes to fall across the interior, with little to no
accumulation expected. Temps tonight fall into the upper 20s
and 30s, so some icy spots are possible, mainly inland and
especially on untreated surfaces.

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY/...
A fast quasi-zonal flow across the lower 48 develops in the
wake of the departing system this weekend. Mid level confluence
over Ontario and the upper Great Lakes will support strong sfc
high pressure moving quickly across NY and New England on Sat,
passing offshore on Sunday.

Sat will be only slightly colder than today, with highs in the
30s to near 40, then colder wx expected for Sat night, with lows
from the single digits well inland to the lower 20s in NYC.

As the high moves offshore on Sunday, a weak upper trough will
approach from the northern Plains. A leading warm front could
bring some light snow to the interior in the afternoon.
High temps on Sunday range from the upper 20s to mid 30s.

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
Jet stream overall remains mainly zonal through the period
across the northern US. This same nearly zonal pattern is
evident in the mid levels also.

At the surface, a warm front associated with an approaching low
Sunday night will have much of its energy north of the region.
However, enough vertical forcing is forecast to have some
precipitation briefly Sunday night into early Monday.

This could very well bring a light snow, under an inch, to
mostly interior locations while the coast may have very brief
snow without much of any accumulation as more rain is expected
towards the coast. A warm front will be moving across with
slowly rising temperatures expected late at night. Temperatures
trend from upper 20s interior to mid 30s along coast for early
evening to lower 30s interior and upper 30s to near 40 along
coast overnight.

Mainly dry conditions thereafter for the rest of Monday with an
associated cold front moving across Monday night. Mostly cloudy
conditions will continue. High pressure will then build in for
Tuesday into early Wednesday. This will help maintain dry
conditions and allow for clouds to decrease.

However, clouds and eventually precipitation are expected to
return for mid to late week as another frontal system
approaches from the west. High pressure moves offshore Wednesday
and an associated warm front slowly moves in. The warm front is
forecast to move across Thursday with an associated cold front
then approaching for Thursday. This is expected to move across
late Thursday night into Friday.

Precipitation chances are forecast Wednesday through Thursday
night. Ambient airmass expected to be cold enough for mostly
snow early Wednesday but then changing more to rain along the
coast in the afternoon and into the night as well. Snow remains
across the interior. Warm sector for the local area Thursday so
pretty much all rain chances in the forecast on Thursday. Rain
chances continue into Thursday night.

Overall, the long term forecast period does not show much
tightness of the pressure gradient so winds are not expected
to get strong. All forecast wind gusts stay under 30 mph.
Temperatures do not exhibit too much of a vast range. Max
temperature ranges from the mid 30s to lower 50s accounting for
all days in the long term. Only one day where some interior
spots may just reach near freezing for the high temperatures and
that day is Wednesday. Min temperatures not too much of range
either in the long term. They range from lower 20s to upper 30s.

&&

.AVIATION /10Z FRIDAY THROUGH TUESDAY/...
Low pressure approaches from the west through today with a warm
front nearing the coast. A cold front moves through tonight.

Expecting lowering conditions to MVFR and then IFR with
localized LIFR as precipitation enters and spreads across the
area. Mainly rain is expected, with a period of light freezing
rain at KSWF this morning. There is a low chance of a brief
period of freezing rain at KTEB and KHPN early this morning, but
with such low chances and confidence, did not include in the
TAF. All terminals, including KSWF, expected to have plain rain
after 16Z.

Winds during much of the TAF period will be S to SW under 10
kts. Some terminals outside of NYC will experience light winds
at or less than 5 kts with variable direction.

Late tonight, KSWF will have a period of rain and snow mix
before all precipitation eventually tapers off from west to
east. Winds eventually become more NW and increase to near 10
kts.

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

Amendments likely for timing of MVFR, IFR, and possibly LIFR.

.OUTLOOK FOR 09Z SATURDAY THROUGH TUESDAY...

Saturday: Becoming VFR in the morning for all terminals. NW
winds 10 to 15 kts with gusts near 20 to 25 kts.

Sunday: VFR during the day, a chance of MVFR or lower conditions
at night in rain and/or snow.

Monday - Tuesday: VFR.

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

&&

.MARINE...
SCA for the ocean extended through daytime Sat and may need to
be extended further into Sunday. Wind gusts to 25 kt in S flow
and seas 5-6 ft this morning should subside for a while this
afternoon, then S swells 5-6 ft return tonight, and N-NW winds
gust to 25-30 kt on all waters daytime Sat between departing low
pressure and building strong high pressure. Leftover 25-kt gusts
on the ocean and ern Sound/bays, and 5+ ft ocean seas, should
subside Sat night as the high builds over the waters, with quiet
cond thereafter through Tue night.

&&

.HYDROLOGY...
There are no hydrologic concerns attm.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...Winter Weather Advisory until 10 AM EST this morning for
     CTZ005-006.
NY...Winter Weather Advisory until 10 AM EST this morning for
     NYZ067>070.
NJ...Winter Weather Advisory until 10 AM EST this morning for
     NJZ002-004-103.
MARINE...Small Craft Advisory until 6 PM EST Saturday for ANZ350-353-
     355.

&&

$$

SYNOPSIS...BG/JM
NEAR TERM...BG
SHORT TERM...BG
LONG TERM...JM
AVIATION...JM
MARINE...BG/JM
HYDROLOGY...BG/JM