000
FXUS61 KOKX 212109
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
409 PM EST Tue Nov 21 2023
.SYNOPSIS...
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Low pressure will approach tonight, and track across the area on
Wed. High pressure then builds in during Thanksgiving Day and
remains in control through at least the first half of the
weekend. A low pressure system may impact the area Sunday into
Monday.-- End Changed Discussion --
&&
.NEAR TERM /THROUGH WEDNESDAY/...
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A 1034 high was centered along the ME coast this aftn, with a broad
area of low pres tracking thru the midwest. This storm sys will
spawn a developing low over near the DELMARVA tngt, then track the
low over the cwa on Wed. The modeling is clustered very closely with
the track of the low, with the ECMWF, NAM, RGEM, and SREF mean all
taking the low over LI.
The low is not progged to get very deep, with the feature around
1005 mb at 15Z per the consensus, but with the tight gradient due to
the high to the NE, there will be a decent wind field ahead of the
low. Based on modeled winds aloft, have issued a wind advy for ern
LI for gusts in the 54-50 mph range. Winds a little less elsewhere,
with gusts around 40 mph coastal areas, dropping to 25-30 mph well
nw of NYC.
A wind driven rain is expected late tngt into Wed mrng with peak
winds coming during the period of heaviest rainfall. Again, the
modeling was in good agreement, so went with the WPC QPF. Around 2
inches of rain with the event, most of it falling overnight.
As the low tracks across the region 12-18Z Wed, winds will lighten
and most of the rain will taper off. Could be some lingering
sprinkles or light rain with the passage of the low, but there
should not be much on the back side with a big dry slot coming thru.
There should be some partial clearing late in the day, but
timeheights attm are not overly optimistic with stratus locked in
around 5000 ft.
For temps, based on the track of the low, much of the area expected
to be warm sectored tngt and Wed. Rising temps tngt into Wed, then
plateauing Wed aftn.-- End Changed Discussion --
&&
.SHORT TERM /WEDNESDAY NIGHT/...
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Mainly dry wx is expected. There is a low chance that a few
sprinkles could work in from the lakes across the interior zones,
particularly in the first half of the night. The probability was too
low to included in the fcst attm. Otherwise, some caa but lingering
clouds should bring temps into the 30s and low 40s by sunrise. The
NBM looked reasonable under these conditions and was used for the
fcst.-- End Changed Discussion --
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
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High pressure builds in during Thanksgiving Day with ridging aloft.
After a breezy start, winds slowly diminish through the rest of the
day. Deterministic NBM has been near the 75th-95th percentile for
high temperatures over the past several runs. With sunny conditions,
some downsloping contribution and 900mb temps progged at 3-4C, have
went with the 95th percentile with a few local adjustments. Highs
generally in the 50s.
High pressure then continues to remain in control through Saturday
with only a weak and dry cold front passing through at some point
late day/early evening Friday. Highs slightly below normal on
Friday, then even colder on Saturday with highs only near 40 in most
spots.
Weak low pressure off the Southeast coast heads north on Sunday,
passing just SE of the 40N/70W benchmark Monday morning. An inverted
trough extending north from the center of the low will bring some
moisture and lift to the forecast area with a chance of rain mainly
Sunday afternoon and night. Looking at GFS and ECMWF, thermal
profiles would support rain, however well north and west could see a
rain/snow mix until at some point perhaps during Sunday night when
thermal profiles warm up.
Likely dry for Monday and Tuesday as the storm heads farther away
east and weak high pressure fills in behind it through Tuesday.-- End Changed Discussion --
&&
.AVIATION /21Z TUESDAY THROUGH SUNDAY/...
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High pressure along the New England coast will continue to give
way to low pressure approaching from the southwest. The low
will track across the area Wednesday morning, passing to the
east by afternoon.
Ceilings will gradually lower to MVFR through this evening as
rain spreads in from the west, eventually lowering to IFR in
moderate to heavy rain overnight. Ceilings will slowly improve
on Wednesday.
ESE winds will steadily increase through the night, increasing
to 10 to 20 kt with G25-35kt. The highest winds and gusts will
be at the coastal terminals where a few gusts may even get
close to 40 kt. Winds will then gradually diminish from west to
east toward daybreak and into the remainder of the morning. As
low pressure moves across the area in the morning, winds may
briefly become light and variable before becoming WNW at 5-10kt.
...NY Metro(KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Timing of ceiling category changes may vary by 1-2 hours.
A few gusts overnight, especially at KJFK, could approach 40kt.
OUTLOOK FOR 18Z WEDNESDAY THROUGH SUNDAY...
Wed Afternoon: Improvement to VFR for the NYC terminals,
elsewhere MVFR conditions may linger into the evening.
Thu: VFR with NW winds 10-15 kt with gusts around 20kt. Locally
higher gusts possible.
Fri-Sat: VFR.
Sun: Mainly VFR. Chance of MVFR in showers late.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
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Gales are still expected tngt into Wed as low pres tracks across LI.
No changes to the warnings. Winds will diminish from W to E during
the day Wed, with sca seas lingering on the ocean thru Wed ngt.
The pressure gradient increases again on Thursday with SCA
conditions on the ocean, and in the morning, possibly on some of the
non-ocean waters as well. Winds and seas diminish through Thursday
night with seas prevailing below 5 ft by Friday morning. Sub-
advisory conditions then continue through Sunday with the exception
of a period of 25kt+ gusts on the ocean Friday night behind a cold
front passage.-- End Changed Discussion --
&&
.HYDROLOGY...
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Around 2 inches of rain is expected thru Wed mrng. Rainfall rates in
the mdt to locally hvy range at times. Ponding, as well as some
minor urban and poor drainage flooding, can be expected. Flash
flooding is not expected attm due to a lack of sustained hvy
rainfall rates.
There are no hydrologic concerns Wednesday night through early next
week.-- End Changed Discussion --
&&
.TIDES/COASTAL FLOODING...
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No changes to current headlines with most of the area under a
coastal flood advisory for the early morning high tide cycle
Wednesday. Statements are in effect for New Haven and New
London Counties in CT and Manhattan for a more localized flood
threat.
There will be an increase in surge tonight into Wednesday
morning due to a strengthening SE flow. There is some
uncertainty with the timing of the max surge and how close to
high tide it occurs. Used a blend of ETSS, ESTOFS and the 50th
percentile of the NYHOPS and then added a few tenths in some
locations the higher NYHOPS (Steven`s) guidance due to
increased SE flow lining up closer to the time of high tide.
In addition, wave action across the ocean front and south shore
of CT in conjunction with heavy rain could enhance water levels
some with the potential for localized moderate flooding.
Surge forecasts are mostly in the 2 to 2.5 ft range with some
locally higher surges up to 3 ft. Parts of the South Shore Bays
and Western LI Sound Shorelines have the higher end of the
surge, more in the 2.5 to 3 ft range.
The early Wednesday morning high tide cycle will be the main
tide cycle of concern with regards to coastal flooding as winds
become more westerly for the next high tide cycle. However,
while this will preclude most additional minor coastal flooding,
some residual minor coastal flooding will still be possible
along the south shore backs bays of Nassau and Suffolk during
the time of high tide Wednesday aft/eve. This would most likely
be localized in nature and due to water levels having some
difficulty draining due to a SE swell.-- End Changed Discussion --
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
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CT...Coastal Flood Advisory from 5 AM to 11 AM EST Wednesday for
CTZ009-010.
NY...Coastal Flood Advisory from 5 AM to 11 AM EST Wednesday for
NYZ071-073.
Coastal Flood Advisory from 1 AM to 7 AM EST Wednesday for
NYZ074-075-178-179.
Coastal Flood Advisory from 4 AM to 10 AM EST Wednesday for
NYZ078-079-176-177.
Wind Advisory from midnight tonight to 10 AM EST Wednesday for
NYZ079-081.
Coastal Flood Advisory from 3 AM to 9 AM EST Wednesday for
NYZ080-081.
NJ...Coastal Flood Advisory from 1 AM to 7 AM EST Wednesday for
NJZ006-106-108.
MARINE...Gale Warning from 1 AM to 1 PM EST Wednesday for ANZ331-332-
340.
Gale Warning from 9 PM this evening to 7 AM EST Wednesday for
ANZ335-338-345.
Small Craft Advisory until 6 PM EST this evening for ANZ350-
353-355.
Gale Warning until 1 PM EST Wednesday for ANZ350-353.
Gale Warning until 7 AM EST Wednesday for ANZ355.-- End Changed Discussion --
&&
$$
SYNOPSIS...JMC/JC
NEAR TERM...JMC
SHORT TERM...JMC
LONG TERM...JC
AVIATION...DW
MARINE...JMC/JC
HYDROLOGY...JMC/JC
TIDES/COASTAL FLOODING...DW