077
FXUS61 KOKX 231438
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
938 AM EST Mon Dec 23 2024
.SYNOPSIS...
High pressure will be in control today. A weak clipper system
approaches tonight and moves through on Tuesday. High pressure
returns Tuesday night and will remain in control through Saturday.
A frontal system slowly approaches Saturday night through
Sunday.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
-- Changed Discussion --
Forecast on track. The coldest air in nearly two years (Since
early Feb 2023) brought lows this morning were in the single
digits for the interior, Southern CT, and LI Pine Barrens, with
lower teens in the NYC metro. There will be some moderation
today compared to Sunday with highs in the mid to upper 20s for
most spots. Some locations in the NYC metro and Long Island
could touch or just exceed 30 degrees, but not anticipating
readings to rise above freezing.
The cold high pressure will remain overhead with light winds.
The center of the high starts moving offshore late as a weak
clipper system approaches from the west. Mostly sunny skies are
expected with a slight increase in clouds towards sunset.-- End Changed Discussion --
&&
.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY NIGHT/...
High pressure continues to shift offshore tonight with an
increase in cloud cover from the west as an approaching clipper
system moves in. Light southerly flow on the back side of the
high combined with the increased cloud cover should allow for
temperatures to be a bit warmer than this morning. Lows will be
in the teens in the interior and 20s along the coast. Temperatures
may actually increase a bit late night as increased southerly
flow ahead of the approaching system brings in more moderate air
from the south.
Regarding the approaching system, a progressive mid level
shortwave and associated weak surface low approach late tonight
and pass by during the day on Tuesday. The bulk of the forcing
will pass north of the area, but there will be a band of light
snow moving in from the west towards day break Tuesday. Thermal
profiles are supportive of all light snow down to the coast
initially. The light snow will be short-lived at any given
location due to the narrow corridor of forcing. The guidance has
also been showing the light snow diminish in coverage as it
moves east of the NYC metro. If any precip lingers near the
coast by mid morning some rain could mix in with the snow. This
will not be a significant event and any snowfall accumulation
will be light with only a few tenths of snow expected, primarily NW
of the NYC metro.
The low pressure associated with the clipper system transfers to
the coast in the afternoon setting up a W-WNW flow, which will
bring improving conditions. Temperatures should also rebound to
more seasonable levels in the middle 30s inland and upper 30s to
near 40 along the coast.
Surface high pressure then builds in from the west Tuesday
night into the day on Wednesday. This will make for another cold
night with lows in the teens for the interior and low to middle
20s along the coast. A slightly below average temperatures are
also expected on Christmas Day with highs only in the low to
middle 30s for much of the area, though high pressure will allow
for mostly clear skies and dry conditions.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
Upper level ridging builds toward the east coast Wednesday night
into Thursday, and then remains through Saturday. The ridge weakens
and moves into the Western Atlantic late Saturday into the beginning
of next week. Meanwhile surface high pressure remains over the
Northeast and Mid Atlantic region through Saturday. The surface high
weakens during Saturday and through next weekend as a frontal system
slowly approaches to the west.
There are timing uncertainties with the upper ridge weakening the
timing of the frontal wave moving into the region, with some
guidance bringing precipitation into the region by Saturday morning,
and other guidance keeping the ridge into Sunday with precipitation
moving into the region as late as later Sunday into the beginning of
next week. With the uncertainties have used the NBM probabilities
which begin slight chances of precipitation Saturday night, and
keeps a chance into Monday.
A slow warm up commences Thursday and continues through the beginning
of next week. Temperatures start out near seasonal normals and rise
above normal for Sunday and Monday.
&&
.AVIATION /14Z MONDAY THROUGH FRIDAY/...
High pressure over the region slides off the coast late in the
day and into tonight. A weak frontal system passes through
Christmas Eve (Tue).
VFR through the TAF period, a low chance of MVFR toward 12Z
Tuesday with light snow.
Light N winds become light and variable early this morning.
Winds gradually shift to S mid to late afternoon, and then back
to SW late tonight.
...NY Metro (KEWR/KLGA/KJFK/KTEB)TAF Uncertainty...
No unscheduled amendments expected. Amendments possible toward
Tuesday morning with light snow developing.
OUTLOOK FOR 12Z TUESDAY THROUGH FRIDAY...
Tuesday: VFR. A chance of MVFR in light snow or a light
snow/rain mix at the coast. Precipitation ending around midday.
Wednesday-Friday: VFR.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90
&&
.MARINE...
-- Changed Discussion --
High pressure over the waters today will shift east as a weak
clipper system passes across the waters late tonight into
Tuesday. High pressure then returns through the end of the week.
Winds and seas will remain below SCA levels through the week.-- End Changed Discussion --
&&
.HYDROLOGY...
There are no hydrologic concerns through next weekend.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...None.
&&
$$
SYNOPSIS...MET/MW
NEAR TERM...DS/MW
SHORT TERM...MW
LONG TERM...MET
AVIATION...BG/MET
MARINE...MET/MW
HYDROLOGY...MET/MW