000
FXUS61 KOKX 091510
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
1010 AM EST Fri Feb 9 2024
.SYNOPSIS...
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A warm front pushes through late today into this evening, with
a cold frontal passage expected late Saturday and into Saturday
night. Weak high pressure builds in on Sunday. Low pressure
approaches from the south and west Monday, deepening and
tracking southeast of Long Island Monday night into early
Tuesday. This low strengthens as it moves southeast of the
Canadian Maritimes Tuesday night into Wednesday. A weak wave of
low pressure traverses the local area thereafter either
Wednesday night or Thursday. Weak high pressure builds in
thereafter.-- End Changed Discussion --
&&
.NEAR TERM /THROUGH TONIGHT/...
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A weak warm front is currently getting to the east. The warm
sector of the large occluded low over the Northern Great Lakes
moves over the area and will allow clouds to dissipate towards
midday and for this afternoon. Southerly flow, decreasing cloud
cover, and a ridge axis moving overhead will bring warmer
temperatures. Have updated temperatures upwards by a degree or
two across the western half of the area, with little to no
change for the eastern third of the area. A wide spread in temps
is expected later this afternoon with middle 40s across far
eastern coastal sections, with 50s, and even some middle and
upper 50s across portions of NE NJ. Used ADJLAV for hourly and
max temp for today as they have initialized much better than
most of the guidance over the past few hours.
Low and mid-level moisture advecting into the area along with weak
PVA over the area may result in some cloud cover redeveloping over
the area tonight. Clouds and persistent WAA from a southerly flow
will keep low temperatures in the middle to upper 30s for most of
the area.-- End Changed Discussion --
&&
.SHORT TERM /SATURDAY THROUGH SUNDAY NIGHT/...
Cloud cover continues to increase into Saturday morning as the cold
front approaches from the west into the day. A wave of low pressure
may develop along the cold front as it makes its approach. The main
area of forcing is expected to move generally to the north of the
area, but there remains at least a chance for showers everywhere on
Saturday, especially into the afternoon. The highest chance of rain
will be for areas to the north and west. It remains possible that
some eastern and coastal areas remain mostly dry with the approach
and passage of the cold front into the evening and Saturday night.
Regardless of showers and cloud cover, Saturday will feature
temperatures well above average with highs into the middle to upper
50s for much of the area. Even coastal areas and the East End of
Long Island should see temperatures in the low to middle 50s. These
temperatures will be anywhere from 10 to 15 degrees above average.
The cold front moves through the area Saturday night with low
temperatures remaining relatively warm, only in the upper 30s to
low 40s.
Despite weak high pressure and drier air moving in behind the cold
front on Sunday, a zonal mid-level flow will allow for temperatures
to remain above average. Highs are expected to remain in the upper
40s to near 50 for much of the area with mostly cloudy to partly
cloudy skies. Cooler air looks to filter into the area Sunday night
with generally clearing skies. Lows Sunday night will be in the
upper 20s for the interior to lower 30s for the coast.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
* A shift farther south has been noted with ensembles with
respect to the storm system and its center of low pressure.
These have shifted farther southeast compared to previous
ensemble runs. The mean snowfall forecast axis has also
shifted farther southeast compared to previously forecast,
resulting in a small increase towards coastal areas. Several
inches of snowfall will be possible but there is a lot of
model spread for precipitation and snowfall.
Upper levels signal a strong jet tapping into multiple sources of
moisture from the Pacific, the Gulf of Mexico and the Western
Atlantic Monday into Monday night. Vertical lift apparent from a
coupled jet structure depicted with local area close to right rear
quad of jet streak to the NE of the area plus left front quad of an
approaching jet streak to the SW going into early Tuesday.
Mid levels convey a strong shortwave moving across the local region
early Tuesday. ECMWF strongest and deepest compared to GFS and
Canadian models. Shortwave moves well east of the region Tuesday
night. Less amplified mid level shortwaves move across Wednesday and
Thursday.
Without much in the way of phasing of northern and southern branches
of the upper jet with the southerly branch being the more dominant
one, there is a limit to how amplified the wave gets. There is not
much tilt vertically. This favors a relatively faster and more
progressive solution. Also evident, is a lack of a strong high
pressure area to lock in colder air. It will difficult to sustain
any prolonged snowfall especially if more of the precipitation falls
during the day. So, the snow will depend on how much dynamic
cooling occurs which will be proportional to the strengthening
of the low.
The trends in ensembles with both ECMWF and GFS has the low
positions for early Tuesday shifting farther offshore. Looking at
grand ensemble incorporating the ECMWF, GFS as well as the Canadian
ensembles, the mean snowfall axis has made its way farther south
from more interior areas to more coastal areas over the last 24
hours.
At the surface, low pressure develops off the mid-Atlantic Monday
night and then deepens as it tracks southeast of Long Island. ECMWF
much deeper and slower compared to other models. The current
forecast takes this low southeast of Long Island going into Monday
night with an increase of precipitation. Similar to previous
forecast, inland zones have relatively more snow in the forecast
compared to the coast. Coastal areas contain mostly rain.
Lesser chances of rain and snow accompany the smaller shortwaves
Wednesday and Thursday with otherwise mainly dry conditions Tuesday
night onward through rest of long term.
Daytime temperatures will be higher than normal, well into the 40s
on Monday but will decline closer to normal values for the rest
of the work week.
&&
.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
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A warm front lifts north of the terminals through this evening.
A cold front approaches early Saturday.
Mainly VFR conditions prevail through the TAF period. Some
pockets of MVFR-IFR possible at outlying terminals through 16z.
S-SSE flow around 10 kt into this afternoon. Winds may be
lighter for inland terminals. S winds weaken tonight with
outlying terminals going light and variable.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Wind speeds could be a few kt higher at times today.
OUTLOOK FOR 12Z SATURDAY THROUGH TUESDAY...
Saturday: MVFR possible at times with a chance of rain showers.
Sunday: VFR.
Monday and Tuesday: MVFR or lower possible with a chance of rain
and/or snow starting Monday, becoming likely Monday night and
chances lingering through Tuesday. N-NW wind gusts 25-30 kt Tuesday.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
High pressure and weak flow over the area will allow sub-SCA
conditions through tonight.
Increasing S/SW flow ahead of a cold front on Saturday will increase
wave heights to 5-6 feet by the afternoon on the ocean. Right now,
gusts are expected to remain below SCA criteria, but may approach
25kt Saturday afternoon and early evening. Residual SCA level waves
are expected to linger into Sunday afternoon before subsiding below
SCA threshold Sunday night.
Sub-SCA conditions Monday and much of Monday night. Then SCA level
wind gusts become likely Tuesday across all waters. Possibility of
gales on the ocean Tuesday into Tuesday night with otherwise SCA
level wind gusts. The SCA level wind gusts remain probable for all
waters through midweek. Ocean SCA levels seas will also become
probable Tuesday through midweek.
&&
.HYDROLOGY...
There are no hydrologic concerns through the weekend. Widespread
precipitation forecast Monday through early Tuesday. Exact
precipitation amounts remain highly uncertain, making for a low
confidence forecast.
&&
.TIDES/COASTAL FLOODING...
Water levels just barely touched minor thresholds across S
Nassau and S Fairfield/Westchester as expected. Guidance has
consistently forecast higher water levels with the AM high tide
cycles both this morning and Sat, with advisories for those
locations and time frames. Minor flooding not expected
elsewhere, though some spots along the lower NY Harbor may come
close. Statements are up for New Haven CT coastline where some
locations may just touch minor coastal flood benchmarks.
Forcing for most of this prolonged event is a combination of
incoming long period swells from on ocean storm, and increasing
astronomical tides due to the new moon on Friday. A storm
passing nearby early next week has potential to produce
widespread minor to locally moderate flooding from Mon night
into Tue night, especially with astronomical tides peaking
during the time frame. The outcome will be highly dependent on
storm track, timing, and intensity, which remain too uncertain
to offer details.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
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CT...Coastal Flood Advisory until noon EST today for CTZ009.
Coastal Flood Advisory from 10 AM to 1 PM EST Saturday for
CTZ009.
NY...Coastal Flood Advisory until noon EST today for NYZ071.
Coastal Flood Advisory from 10 AM to 1 PM EST Saturday for
NYZ071.
Coastal Flood Advisory from 6 AM to 9 AM EST Saturday for
NYZ179.
NJ...None.
MARINE...None.-- End Changed Discussion --
&&
$$
SYNOPSIS...JM/MW
NEAR TERM...JE/MW
SHORT TERM...MW
LONG TERM...JM
AVIATION...JM/DS
MARINE...JM/MW
HYDROLOGY...JM/MW
TIDES/COASTAL FLOODING...