540
FXUS61 KOKX 010949
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
449 AM EST Sat Feb 1 2025
.SYNOPSIS...
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Low pressure moves well out into the Northern Atlantic and
deepens today. High pressure will build in today into tonight
from the Great Lakes. This high pressure area will move offshore
Sunday into Sunday night, eventually getting to southeast of the
Canadian Maritimes. Low pressure approaches Sunday into Sunday
night from Southeast Canada with its associated warm front
moving across Sunday night. The warm front shifts north of the
area Monday with an associated cold front moving across Monday
night. High pressure will build from the northwest on Tuesday,
then move east on Wednesday as a complex frontal system
approaches from the southwest from later Wednesday into
Thursday. High pressure should return on Friday.-- End Changed Discussion --
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
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Northerly flow starting to become gusty behind a departing wave
of low pressure. Outside of perhaps some very light rain for
eastern portions of the region into early this morning, the
precipitation has ended. With drier air moving in on this
northerly flow, fog will breakup and visibilities will continue
to increase going into this morning.
Temperatures have not changed too much but do expect some
lowering going into this morning and then another decrease of
temperatures this afternoon.
High pressure from the Great Lakes will be building in through
the day. The relatively tight pressure gradient between this
high pressure area and an area deepening low pressure out in the
Northern Atlantic will create a gusty NW flow, advecting in
colder air throughout the day.
Expecting actually colder temperatures this afternoon compared
to this morning. Used a colder blend of guidance for high
temperatures which will be set in the morning and range mainly
in the low to upper 30s. Low 30s for the interior and upper 30s
along the coast and within NYC.
Some mid level ridging will allow for more subsidence and drying
atmospheric column will make for a sunnier day. But with cold
air advection, actual temperatures will be colder than the
previous day and apparent temperatures will certainly feel much
colder than the previous day. The highest the forecast wind
chills reach today is the upper teens to upper 20s.-- End Changed Discussion --
&&
.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
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Expecting potentially 2 precipitation events during the short
term. Temperatures colder for tonight and Sunday, then quickly
rebound and moderate Sunday night through Monday night.
Temperatures average below normal tonight and Sunday, then above
normal Sunday night, Monday, and Monday night.
The mid level ridging continues tonight into early Sunday. A
less amplified mid level shortwave moves across Sunday night.
Nearly zonal flow follows in the mid levels Monday through
Monday night. A strong shortwave approaches by early Tuesday but
has much of its energy well north of the region.
At 850mb, relatively colder air around -10 to -12 degrees C
first half of tonight, increases overnight into Sunday. The
increasing trend continues Sunday night into Monday with
increasing SW to W winds, increasing the low level warm air
advection. The temperatures decrease again Monday night.
At the surface, high pressure continues building in tonight,
with its center going to right north of the local area by early
Sunday. Then, this high pressure area will eventually shift to
more east of the region, getting out into the Gulf of Maine
late Sunday and southeast of the Canadian Maritimes Sunday
night.
Meanwhile a complex low pressure area and associated frontal
system will be approaching the region for Sunday night into
Monday night. Associated warm front moves across Sunday night
and associated cold front moves across Monday night.
Higher POPs and more precipitation are forecast with the warm
front and much less with the cold front. The first precipitation
event of this forecast for Sunday night could produce up to near
1 to 1.5 inches of snow for the interior with little to no snow
(less than 0.3 inches of snow) along the coast.
Regarding temperatures, tonight with anticipated optimal
radiational cooling conditions, used the relatively cooler MET
guidance for lows tonight. This conveys a more vast range and is
colder than the MAV guidance. Used a combination of MAV, MET,
and NBM for high temperatures Sunday, more of NBM and raw model
temperature blend Sunday night and then multiple blends of model
data for temperatures Monday and Monday night.-- End Changed Discussion --
&&
.LONG TERM /TUESDAY THROUGH FRIDAY/...
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Fairly good model consensus continues on a fast zonal flow aloft
over the CONUS, with an embedded shortwave trough bringing sensible
wx during mid to late week. After a cold frontal passage early Tue
AM, strong high pressure will build down from the NW for later Tue
into Wed, with colder air arriving by Tue night after a relatively
mild but brisk day with highs in the 40s.
Given the fast flow aloft have brought in precip chances well ahead
of deterministic model fcst, with chance of light snow Wed mainly in
the afternoon, and categorical PoP for Wed night/Thu AM. As the high
retreats and warmer air moves in especially aloft, partial
thicknesses suggest we should see a transition to a wintry mix,
becoming all rain for NYC metro/Long Island late Wed night and
throughout by daytime Thu, with temps on Thu rising to the upper
40s/lower 50s. Precip chances wane Thu night, with fair wx and temps
closer to the seasonal avg for for Fri.-- End Changed Discussion --
&&
.AVIATION /09Z SATURDAY THROUGH WEDNESDAY/...
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Deepening low pressure will move east of the area as strong high
pressure builds from the upper Great Lakes.
Widely varying cond attm, with LIFR cigs at KGON/KSWF and MVFR
elsewhere, as winds shift to the N behind the departing low.
VFR at most terminals by 13Z, taking longer at KISP/KGON to the east
and KSWF to the northwest (15Z-16Z).
NNW winds should increase 15-20 kt with gusts 25-30 kt. A few higher
gusts up to 35 kt are possible especially this morning.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Amendments still possible for timing of flight cat changes and
increase in N-NW winds.
.OUTLOOK FOR 06Z SUNDAY THROUGH WEDNESDAY...
Late tonight: VFR. NW winds 10-15 kt with gusts 20-25kt early in the
evening, then diminishing.
Sunday: Chance of MVFR or lower cond at night in rain and/or snow.
Monday and Tuesday: VFR.
Wednesday: Chance of light snow with MVFR or lower cond mainly in
the afternoon.
Wednesday night: MVFR or lower cond likely. Precip type snow
initially, changing to a wintry mix in the evening, then to rain at
the NYC metro/Long Island terminals 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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With the relatively tight pressure gradient between approaching
high pressure from the north and west and deepening low pressure
well to the north and east, a gusty NW flow will reach SCA
levels for all waters throughout today. SCA already in effect on
the ocean and after 6AM goes into effect for all forecast
waters.
The SCA continues into tonight with continued gusty NW winds.
Non-ocean SCA extended until 8PM to account for frequent early
evening gusts near 25 kt anticipated. Then, non-ocean waters go
below SCA thresholds after 8PM while the ocean waters remain
with SCA. Western ocean zone SCA goes until 1AM EST while the
the eastern ocean zones continue for the entire overnight.
A relatively weak pressure gradient will keep conditions below
SCA on all waters Sunday through Monday night.
NW winds on Tue could gust close to 25 kt on the ern ocean waters
daytime Tue, otherwise sub SCA cond expected Tue-Wed.-- End Changed Discussion --
&&
.HYDROLOGY...
There are no hydrologic concerns at this time.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
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CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory until 8 PM EST this evening for ANZ331-
332-335-338-340-345.
Small Craft Advisory until 6 AM EST Sunday for ANZ350-353.
Small Craft Advisory until 1 AM EST Sunday for ANZ355.-- End Changed Discussion --
&&
$$
SYNOPSIS...BG/JM
NEAR TERM...JM
SHORT TERM...JM
LONG TERM...BG
AVIATION...BG
MARINE...BG/JM
HYDROLOGY...BG/JM