Area Forecast Discussion
Issued by NWS Upton, NY

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FXUS61 KOKX 310021

Area Forecast Discussion
National Weather Service New York NY
721 PM EST Mon Jan 30 2023

A weak cold front passes through the area overnight into early
Tuesday morning. High pressure builds from the west Tuesday
through Wednesday. Meanwhile a weak low passes to the south of
the area Tuesday night into early Wednesday morning. The high
will slide offshore on Thursday, followed by an arctic cold
frontal passage early Friday and cold high pressure building in
for the first half of the weekend. A frontal system will then
impact the area Sunday into Sunday night.


A weak cold front just NW of the Lower Hudson Valley will
work slowly across the area through the overnight. There is
little forcing or moisture with the front and any precipitation
that occurs will be light. With the slower push of the front
have delayed probabilities until later this evening, and mainly
late, and into the overnight. Profiles support rain ahead of the
front and then a mix of rain and snow behind the front late
tonight. The front moves south early Tuesday morning, and there
will be slight chances of precipitation across Long Island.
Also, with the delay in the colder air overnight low
temperatures will be similar to Monday morning`s.


A cold front pushes to the south of Long Island early in the
morning, and any remaining rain and snow showers will be ending.
Weak cold advection Tuesday morning weakens and ends Tuesday
afternoon with a colder airmass remaining in place Tuesday
night. Another wave of low pressure will track along the cold
front, which should be well to the south of the region, late
Tuesday night. With the cold airmass and light winds as high
pressure builds in, outlying areas may radiate before clouds
thicken overnight, especially to the south. The southern
portion of the region may be on the northern fringe of the
precipitation, and will a strong upper level jet of 110-130kt
there may be a few flurries across portions of northeastern New
Jersey into Long Island.


The northern branch of the polar jet will become the dominant
stream this period as a quick shot of arctic air arrives Friday
into Saturday. This will rival the airmass that arrived this
past Christmas eve with temperatures Friday night and Saturday
about 25 degrees below normal. The arctic cold front slips
through Friday morning. There are some differences in the
timing, but all bring in the coldest air Friday night with 85h
temps dropping to around -25C and in some cases approaching
-30C. With no downstream block over the north Atlantic, this
will be a fleeting airmass, in and out as fast as it came in. In
addition, with strong NW winds behind the cold front, gusts of
25 to 35 mph will produce wind chills at the very least at
advisory criteria with a small chance of reaching warning levels
inland. Lows Friday night inland are forecast to drop several
degrees below zero with the single digits at the coast. For
highs Saturday, most locations will be in the teens.

High pressure then builds over the area Saturday and offshore
Saturday night with a return flow and strong warm advection.
After the very cold shot, will have to watch for condensation on
roadway surface Saturday night. Temperatures will rise through
the night to near freezing at the coast, and around 20 well
inland. An approaching frontal system will then bring a slight
chance of snow in the morning, which transitions to mainly rain
in the afternoon. Once again with the cold ground, there could
be the potential for pockets of freezing rain even with
temperature rising above freezing. Some of the precipitation
could then end with some snow mixing back in Sunday night.
However, this does not look to be a significant winter
precipitation event.

Temperatures Sunday into Monday will run several degrees above


A cold front moves through towards and just after midnight, with
weak high pressure building to the west and north on Tuesday.

VFR through this evening. Cigs start to lower late this evening with
the frontal approach and passage, bringing the potential for brief
MVFR cigs just before the morning push, mainly towards 6 to 10z.
Conditions will be VFR by 10-12z at all terminals. The weakening
boundary may squeeze out a few light rain/snow showers as it passes
through overnight, with best chance of occurrence at KSWF. If shower
activity makes it all the way to the coast it will likely be in
the form of rain.

Generally a light S / SW flow takes place thru the remainder of the
evening, and then veers to the NW and increasing to around 10-12 kt
towards the morning push. Winds will continue out of the N and NW
through the day Tuesday at around 10 kt.

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

Timing of the wind shift late tonight may be off by an hour or two.

MVFR cigs occurrence is low confidence for about a four hour period
late tonight into early Tuesday morning.

.Tuesday night through Thursday...VFR.
.Friday...VFR. NW winds increase to 15-20 G30 kt.
.Saturday...VFR. NW winds 15 G20 kt early.

Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/


Winds and seas will remain below advisory levels tonight through
Tuesday night as a weak cold front passes through the waters
tonight and high pressure builds in from the west Tuesday and
Tuesday night.

High pressure builds offshore Thursday ahead of an approaching
arctic cold front. Strengthening SW winds ahead of the front
will likely bring SCA conditions to the waters Thursday night
with post-frontal NW gales likely Friday into early Saturday.


No hydrologic impacts expected.





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