discussion on 2023-11-26

000
FXUS61 KOKX 261146 CCA
AFDOKX

Area Forecast Discussion...CORRECTED
National Weather Service New York NY
646 AM EST Sun Nov 26 2023

.SYNOPSIS...
High pressure continues to slowly move off the New England coast
today. Low pressure then impacts the area late today, tonight, and
into early Monday morning. High pressure slowly builds into the
region Monday through Tuesday night, and noses in from the south
on Wednesday, and then weakens as low pressure passes to the
north. The high, centered to our south and east, remains in
control through at least early Friday. Low pressure impacts the
area late Friday into the weekend.

&&

.NEAR TERM /THROUGH TONIGHT/...
Updated for current conditions. Temperatures and dew points
continue to be lower than forecast with near calm wind, and a
high thin overcast.

A large upper trough will be approaching from central Canada
and the central United States today and passing through the
region today, with the trough axis passing offshore by 12Z
Monday. Southern energy phasing with the trough will developing
a low off the North Carolina coast and as the upper trough
become negative tonight the low will be deepening and tracking
along the coast. With the progressive nature of the trough the
surface low quickly passes through the region tonight, and will
be well to the north Monday. With strong isentropic forcing
developing this afternoon ahead of the deepening low
precipitation chances will be increasing from the south.
Precipitation will be possible by late in the day. And, with the
strong lift and an increasing low level jet, a period of
moderate to heavy rainfall will be possible tonight. With the
quick moving system rainfall amounts have lowered a little from
previous forecast cycles.

&&

.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
Rain will be quickly ending across the east and northeast
portion of the region early Monday as the surface low wraps up
and tracks to the northeast and north. Gusty winds, and a cold
airmass moving into the region will be the main effects in the
wake of the low Monday through Tuesday night, as the low
continues to deepen across eastern Canada and high pressure
builds to the west. Also, with cyclonic flow continuing a weak
surface trough will be rotating into the region late Monday
night into Tuesday, and with a strong westerly flow, with
moisture coming off Lake Erie, and cold air in place a few
flurries will be possible across the interior during Tuesday,
and have added this to the forecast.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
Guidance is generally in agreement Wednesday through the first
half of Friday. The long term period starts off with high
pressure nosing in from the south as the flow becomes zonal
aloft. The high quickly gets suppressed to the south as low
pressure passes well to our north as it tracks through Canada.
The high remains centered to our south and east through early
Friday and results in a long period of southwesterly flow. This
will allow for a warming trend. High temperatures on Wednesday
will be in the mid 30s to low 40s and by Friday they will be in
the upper 40s to mid 50s. Long Island and the CT coast will be
on the warmer side of this range each day due to the flow off
the warmer waters.

Late Friday and into the weekend is where the model spread
starts to increase. There is agreement on an upper level low
moving on the west coast from the Pacific and then opening up as
it digs down into the southwest CONUS. This shortwave then
lifts through the central CONUS towards our area. The
disagreement is in the associated surface low, with difference
in strength, timing and location. Ended up going a bit lower
than the NBM with the PoPs due to low confidence. PoPs start
Friday afternoon and peak Friday night, with lingering PoPs
through the weekend. At this time, thermal profiles show an all
plain rain event. The NBM currently shows a 10-15% chance of 1
inch of rain during any 24 hour period during this event.

&&

.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
-- Changed Discussion --High pressure shifts farther offshore today. Low pressure
impacts the area tonight into Monday morning.

VFR this morning and much of the afternoon. MVFR conditions
expected by late afternoon and then eventually IFR overnight.

Winds start of variable or light out of the SE. Winds increase
through this evening, peaking at 12-17 kt. Low pressure will
pass directly overhead and this will lead to a period of a low
confidence wind forecast around 02z-07z. As the low pulls away,
winds eventually become W and start to increase again early
Monday.

Cigs lower this morning, but likely stay VFR through much of the
afternoon. There is potential for cigs to lower to MVFR earlier
than the TAF. Around 02z-03z cigs lower to IFR and rain becomes
moderate. This will last several hours before a quick
improvement to MVFR then eventually VFR early Monday morning.

Higher confidence in LLWS farther east and have added in the TAF
for KBDR, KISP and KGON. Less confidence farther west but can not
completely rule out a brief period of LLWS.

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

Cigs could lower to MVFR earlier than forecast.

Low confidence wind forecast around 02-07z.

OUTLOOK FOR 12Z MONDAY THROUGH THURSDAY...

Mon: Improvement to VFR in the morning. WNW wind 15-20kt, G25-30kt.

Tue: VFR. W wind 15-20kt, G25-35kt.

Wed: VFR. SW wind 10-15kt, G20kt.

Thu: VFR. W wind 10-15kt, G20kt.

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

&&

.MARINE...
No changes to winds and seas at this time.

High pressure will be moving further off the New England coast
today as a deepening low off the North Carolina coast tracks
toward the region by late in the day and then across the
forecast waters tonight, moving quickly to the northeast late
tonight into Monday. Small craft advisory conditions are
expected to develop across all but the New York Harbor waters
tonight, and then in the wake of the low Monday, SCA conditions
are also expected on New York Harbor. There may be a break of a
few hours when conditions are below advisory levels late tonight
as the low tracks through the waters. However, with the brief
break, and then winds and wave increasing in a westerly flow
have issued a SCA for all but the New York Harbor beginning
tonight and continuing through Monday night, and then including
New York Harbor Monday through Monday night.

As the low tracks northerly into eastern Canada Monday through
Tuesday, and deepens, the pressure gradient across the forecast
waters will be increases as high pressure also builds slowly to
the west. Small craft advisory conditions will remain on the
forecast waters Tuesday and Tuesday night, and there is a chance
that gusts reach gale force on the ocean waters Tuesday
afternoon into Tuesday evening, and possibly on the Long Island
bays and Long Island Sound for a few hours Tuesday evening.

SCA conditions continue Wednesday through at least Thursday as
the area remains in between high pressure to the south and low
pressure to the north. 25 to 30 kt gusts are possible across all
waters during this time period except the NY Harbor and the
western LI Sound. On the ocean waters, waves will be 4 to 6 ft.
Sub SCA conditions then expected through the weekend, although
the forecast winds and waves can trend higher with low pressure
impacting the area.

&&

.HYDROLOGY...
There are no hydrologic concerns from around one half to three
quarters of an inch of rainfall late today into early Monday
morning.

There are no hydrologic concerns Tuesday through the weekend at
this time.

&&

.TIDES/COASTAL FLOODING...
Astronomical tides will be increasing into early next week due
to a full moon early Monday morning. Water levels should fall
just below minor benchmarks during the this mornings high tide
for a few vulnerable locations across the south shore back bays
of Nassau, the NY Harbor and along coastal Fairfield.

Minor coastal flooding looks more likely for the south shore back
bays of Nassau and Queens, the Lower NY Harbor and the bays along
the SE coast of Long Island with the Monday morning high tide. A
quickly developing low pressure may help bring enough of a surge
(only around 0.50-0.75 ft needed) to reach minor benchmarks.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory from 6 PM this evening to 6 AM EST
     Tuesday for ANZ331-332-335-340-345-350-353-355.
     Small Craft Advisory from 6 AM Monday to 6 AM EST Tuesday for
     ANZ338.

&&

$$

SYNOPSIS...MET/JT
NEAR TERM...MET
SHORT TERM...MET
LONG TERM...JT
AVIATION...JT
MARINE...MET/JT
HYDROLOGY...MET/JT
TIDES/COASTAL FLOODING...