okx-afd on 2025-02-14

338
FXUS61 KOKX 142040
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
340 PM EST Fri Feb 14 2025

.SYNOPSIS...
-- Changed Discussion --High pressure builds across the region through Saturday. Low
pressure tracks through the area on Sunday. Strong low pressure
moving from upstate New York toward the Canadian Maritimes
Sunday night will bring a cold front through, with high pressure
slowly building from the west in its wake from Monday through
Wednesday. Low pressure organizing along the northern Gulf Coast
on Wednesday will then move up the Southeast coast Wednesday
night and intensify into a major winter storm off the Mid
Atlantic coast Thursday into Thursday night, which should then
move east of New England on Friday.-- End Changed Discussion --

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
-- Changed Discussion --High pres builds over the area tngt. Winds will decrease but
high clouds will increase ahead of the next sys. The increasing
clouds should keep temps from completely bottoming out, and the
NBM with minor adjustments was used.-- End Changed Discussion --

.SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY/...
-- Changed Discussion --The modeling remains consistent for the weekend storm. Timing of
the onset of snow generally holds off until 18Z or later per
the consensus. Could be some initial flakes invof Port Jervis
prior to that time. The snow increases in intensity late in the
aftn and eve, then transitions to sleet and rain from S to N
aft 00Z. Across the interior, the pcpn transitions to sleet and
fzra instead, before warming abv freezing Sun mrng. The raw
model blend looked best to lock in the cold llvl air across the
interior so went close to that for temps Sun. Some cstl/ern
areas could be in the lower 50s while nwrn interior remains in
the 30s.

Trended snow totals slightly lower with the surge of waa, but
did not want to pull back too much yet with an initial few
hours of mdt to locally hvy snow at the front end of the sys.

No changes to icing amounts. Up to a quarter inch of ice seems
on track for this sys. As always, there is some uncertainty wrt
exact transition times. It is possible that the advy may need to
be extended a few hours longer Sun mrng for the extreme nwrn
tier where light flow around 070 is locked in, but no changes
to the advy have been made attm.-- End Changed Discussion --

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
-- Changed Discussion --Key Points:

* Colder and windy conditions expected early next week after a cold
frontal passage Sunday night.

* Potential is increasing for a major winter storm from Wednesday
night into Thursday night.

Complex pattern developing over North America during this time
should help lock in cold air, with one large closed low developing
over eastern Canada and another in its wake over the northern Plains
and upper Great Lakes. At the surface, strong low pressure moving
from upstate New York toward the Canadian Maritimes Sunday night
will bring a cold front through, with colder and brisk conditions
for Monday and possibly into Tuesday via a tight pressure gradient
between the low and strong high pressure off to the west.

Meanwhile, shortwave energy moving onshore the West Coast early next
week should dive toward the southern Plains by Wed AM and initiate
sfc cyclogenesis along the northern Gulf coast daytime Wed. The
degree to which this system phases with the northern Plains closed
low will determine the track and intensity of the developing sfc low
as it moves up the Southeast coast Wed night and then off the Mid
Atlantic coast Thu/Thu night, pulling away on Fri. There is
increasing potential for a major winter storm to impact the area
from Wed night into Thu night with heavy snow during this time, also
strong N winds Thu night--the 12Z ECMWF ensemble control run shows
an intense low off the Mid Atlantic coast passing just outside the
40N/70W benchmark Thu night, bringing major snowfall for all the I-
95 cities from DC to Boston, with its axis of heaviest snowfall very
close or just south and east which make sense given that storm
track, while the ensemble control run shows widespread 50-60%
potential for 6 or more inches of snow during this time. The
Canadian model and its ensemble are in close agreement, while the
deterministic GFS/ICON are suppressed, showing the heaviest snow
mostly away from the big cities, impacting eastern Delmarva and
southern NJ over to the Cape and Islands of MA. That said, the GEFS
does show some ensemble members supporting the ECMWF/Canadian
solution. Enough confidence in winter storm potential exists to
include mention in the HWO.-- End Changed Discussion --

.AVIATION /21Z FRIDAY THROUGH WEDNESDAY/...
-- Changed Discussion --High pressure moves overhead tonight. Low pressure approaches
the area on Saturday.

VFR through Saturday morning. Cigs and vsbys lower through
Saturday afternoon and evening.

Winds and gusts diminish this evening, with gusts ending around 00Z
Saturday. Winds become light and variable late tonight through early
Saturday morning. Winds then become southeasterly under 10 kt
through the end of the TAF period.

Snow is expected by Saturday afternoon. MVFR vsbys expected
around 20z, with vsbys as low as 3/4 of a mile possible in
pockets of heavier snow. Cigs lower to MVFR around 20z as well,
with IFR cigs possible 22z.

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

Amendments possible for flight category changes to cigs and
vsbys with snow moving in Saturday afternoon.

.OUTLOOK FOR 18Z SATURDAY THROUGH WEDNESDAY...

Saturday Afternoon-Saturday Night: IFR in snow in the
afternoon. The snow should transition to rain along the coast in
the evening, and inland overnight. A wintry mix may remain at
KSWF for the entire overnight hours, including freezing rain.

Sunday: IFR or lower with rain. A chance of freezing rain at KSWF
early in the morning. LLWS possible, especially east of the city
terminals. S Gusts 20-25 kt.

Monday: VFR with W wind gusts 35-40 kt.

Tuesday: VFR with W wind gusts around 25 kt.

Wednesday: 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 --A sca remains in effect this eve, then winds and seas blw sca
lvls thru Sat. Winds and seas increase Sat ngt and Sun when sca
will likely be needed.

W gales are likely on the ocean and the ern Sound/Bays Sunday night,
then on all waters daytime Mon. Sustained winds on the ocean likely
to reach gale force during this time, with gusts 40-45 kt, with
sustained 30 kt winds and gusts 35-40 kt likely on the non-ocean
waters. Winds shift NW and diminish Mon evening but should still be
at gale force during the evening on all waters, then on the ocean
and open Sound waters late Mon night. SCA cond should follow for all
waters on Tue, gradually subsiding Tue night. Quiet cond expected on
Wed with high pressure briefly over the waters ahead of an
approaching winter storm beyond the end of the forecast period.-- End Changed Discussion --

.HYDROLOGY...
-- Changed Discussion --
No hydrologic impacts are expected through next Fri.-- End Changed Discussion --

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...Winter Weather Advisory from noon Saturday to 7 AM EST Sunday
for CTZ005>008.
Winter Weather Advisory from noon Saturday to 1 AM EST Sunday
for CTZ009>012.
NY...Winter Weather Advisory from noon Saturday to 7 AM EST Sunday
for NYZ067-068.
Winter Weather Advisory from noon Saturday to 1 AM EST Sunday
for NYZ069>071.
NJ...Winter Weather Advisory from noon Saturday to 7 AM EST Sunday
for NJZ002.
Winter Weather Advisory from noon Saturday to 1 AM EST Sunday
for NJZ004-103>105.
MARINE...Small Craft Advisory until 7 PM EST this evening for ANZ331-
332-335-338-340-345-350-353-355.

SYNOPSIS...JMC/BG
NEAR TERM...JMC
SHORT TERM...JMC
LONG TERM...BG
AVIATION...JT
MARINE...JMC/BG
HYDROLOGY...JMC/BG