000
FXUS61 KOKX 190021
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
721 PM EST Mon Dec 18 2023
.SYNOPSIS...
Strong low pressure lifts into southeast Canada tonight. High
pressure then slowly builds into the area on Tuesday, remaining
in control through the upcoming weekend.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
-- Changed Discussion --
Minor changes were made to cloud coverage with otherwise no
other changes made. Forecast remains on track.
Strong low pressure with one center over southeast Canada
and another over southern New England will continue lifting to
the northeast this evening. Rain has quickly lifted north of the
area with dry conditions expected this evening.
Pressure rises behind the low will support a gusty W-WNW flow
into the evening. Sustained winds 15-20 mph with gusts 25-35
mph are likely. A few gusts up to 40 mph cannot be ruled out. No
additional headlines are anticipated. While there will continue
to be pressure rises through the night, they will not be as
steep as late this afternoon and evening. Wind gusts 25-30 mph
likely continue through about 03z near the coast, and then
weaken to about 15-20 mph thereafter. Gusts likely end across
the interior overnight.
The middle and upper levels dry out tonight, but there will be
some lingering lower level moisture. Cyclonic flow and the
lingering moisture supports some stratocu clouds overnight,
especially for the interior. Skies may become mostly cloudy
towards day break as the trailing upper low begins to move
overhead. Have left a slight chance PoP for western Orange
County as some light precip cannot be completely ruled out.
Moisture appears rather shallow so not enough confidence to go
higher than slight chance. The precip could be in the form of
flurries/light snow if any develops.
Lows tonight will be in the 30s, slightly above normal for this
time of year.-- End Changed Discussion --
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/...
The upper low swings across the region on Tuesday. Any
flurries/light snow showers across Western Orange should dissipate
shortly after 12z. Will continue to carry a slight chance through 9
am. Otherwise, mostly cloudy skies are likely to start the day.
The trough axis shifts east in the afternoon which should allow
clouds to diminish in coverage. High pressure builds into the
region through the day. The pressure gradient between the high
to our west and departing low pressure well to our northeast
will keep breezy conditions in place. NW winds 10-15 mph with
gusts around 20 mph are possible. Highs will be near seasonable
levels in the lower to middle 40s.
The high remains just to our west Tuesday night. The departing
upper low likely begins to stall offshore to our southeast.
Heights overhead will rise with ridging returning. Winds will
likely not go completely calm, but should lighten considerable
at night. Skies will become mostly clear with dry conditions
leading to a chilly night. Temperatures will be in the 20s for
most locations except the NYC metro where lows will be near 30
degrees.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
The large scale numerical weather prediction models in the
upper levels exhibit strong jet exiting farther northeast of
the region for midweek. No other strong southerly jet streaks
are forecast within the region thereafter through early next
week with dominant westerly component to the upper level flow.
This will allow for the airmass to remain mostly dry.
Mid week into the start of the weekend looks to have dominance
of surface high pressure judging from the consensus of large
scale numerical weather forecast model depictions of MSLP,
precipitation and winds. The Wednesday morning through Saturday
morning time period is expected to have a prevalence of dry
conditions.
Overall, near normal temperatures forecast generally looking at
extended guidance for Wednesday and Thursday, trending to colder
than normal Thursday night and Friday. Then, temperature trends in
the guidance climb closer to normal for Saturday and then above
normal for Sunday as well as Christmas Day.
For Saturday afternoon through rest of the weekend, despite
surface features amongst the large scale numerical weather
prediction models depicting high pressure nearby, in the mid
levels, ridging appears to break down. In the mid levels, there
is indication for some shortwave activity near the area with
associated positive vorticity advection. This could result in
some light precipitation for parts of the region. There is a lot
of uncertainty this far out in time so it is difficult to go
beyond 20 percent chance for precipitation. The precipitation by
some of the models does not appear to be significant so
Saturday afternoon through the rest of the weekend is forecast
to be mostly dry. Only have some slight chance of rain or snow
showers for parts of the region in the Saturday afternoon into
Saturday evening timeframe and this takes into account wet bulb
cooling.
For Christmas Day, more of a mid level ridging trend is indicated
in the 500mb height pattern forecasts amongst the large scale
numerical weather prediction models with surface high pressure
also depicted across the area. Dry conditions are forecast.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
-- Changed Discussion --
Strong low pressure lifts northward across Northern New England
and eastern Canada tonight. At the same time, a trough of low
pressure approaches from the west, passing through the area on
Tuesday.
Mainly VFR conditions are expected through the TAF period.
However, ceilings on Tuesday may occasionally go MVFR, with
highest chances for KSWF and KHPN.
SW winds overnight will gusts to around 20 kt, mainly
at the coastal terminals. Winds will then veer to the W after
12Z, increasing to 10-15kt G20-25kt, becoming NW in the
afternoon.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Chance of brief MVFR ceilings Tuesday, mainly in the morning
into the early afternoon.
OUTLOOK FOR 00Z WEDNESDAY THROUGH SATURDAY...
Tuesday Night: NW G20 kt early in the evening, mainly at the
coastal terminals.
Wednesday through Saturday: VFR.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
-- Changed Discussion --
The Gale warning was allowed to expire on the NY Harbor, LI
Bays, and most of the LI Sound except east of Orient and the
Connecticut River. These waters now have a small craft advisory
was goes through all of tonight. The Gale Warning on the
easternmost LI Sound zone and ocean will go until 02z. Solid SCA
conditions are then expected through the rest of the night as
winds gust 25-30 kt. SCA gusts are likely Tuesday morning on the
ocean. Some SCA gusts will be possible Tuesday morning on the
non-ocean waters. Otherwise, winds on the waters should remain
below SCA levels through Tuesday night. Ocean seas will remain
elevated through Tuesday night necessitating the continuation of
an SCA.
Looking at the marine long term forecast covering Wednesday
through Saturday night, expecting a continuance of SCA level
ocean seas Wednesday through Friday night with wind gusts also
meeting SCA thresholds for mainly Wednesday through Friday
timeframe. The forecast then shows a decline in these ocean seas
for Saturday, with an eventual return to below SCA seas that
will remain below SCA through Saturday night. For the non-ocean
waters, mainly below SCA conditions are forecast for the much of
the marine long term period but for Thursday into Thursday
night, parts of the non-ocean waters are forecast to have some
SCA level gusts.-- End Changed Discussion --
&&
.HYDROLOGY...
Residual river flooding will then continue tonight and
potentially into early Tuesday. Afterwards, no hydrologic
impacts expected through next weekend.
&&
.TIDES/COASTAL FLOODING...
-- Changed Discussion --
Residual coastal flooding continues into early this evening
across portions of SW Suffolk coastline but is expected to be
below minor benchmarks for flooding before 8pm.
Other locations have fallen with their total water level and
remain below minor coastal flood thresholds.
Along the ocean beachfront, potential exists for 12-16 ft breakers
today (8-12ft for NYC beachfront), which combined with elevated
water levels, will likely result in widespread dune erosion and
scattered overwashes.
Otherwise, no additional coastal flooding is anticipated
tonight through the middle of the week.-- End Changed Discussion --
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
CT...None.
NY...Coastal Flood Warning until 8 PM EST this evening for NYZ080.
NJ...None.
MARINE...Small Craft Advisory until 6 AM EST Tuesday for ANZ331-335-338-
340-345.
Gale Warning until 9 PM EST this evening for ANZ332-350-353-
355.-- End Changed Discussion --
&&
$$
SYNOPSIS...JM/DS
NEAR TERM...JM/DS
SHORT TERM...DS
LONG TERM...JM
AVIATION...DW
MARINE...JM/DS
HYDROLOGY...JM/DS
TIDES/COASTAL FLOODING...