239
FXUS61 KOKX 171459
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
959 AM EST Mon Feb 17 2025
.SYNOPSIS...
Deepening low pressure meanders near the Canadian Maritimes today
as a strong high drops down into the Central US. The high gradually
builds into the region from the west through midweek. An area of
low pressure then ejects off the Southeast coast Wednesday night,
passing south and east of the area Thursday. High pressure returns
from the west for the end of the week.
&&
.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
No significant changes from the previous update. Have extended
the mention of sct flurries for parts of the Lower Hudson
Valley and Southern CT through 18z.
Sharply colder today while remaining very gusty. The local
effects from a deepening sub 970 mb low continue to be felt as
the system occludes and meanders over far southeastern Canada.
The result is the continuation of strong, locally damaging,
winds across the region. CAA with the flow is ushering in a
sharply colder air mass relative to yesterday as well.
Afternoon highs today climb little from where they started near
daybreak, topping out within a few degrees of the freezing
mark. With the winds, expect wind chill values to remain
persistently in the 20s thru the day, if not lower.
Soundings indicate a well mixed boundary layer, mixing to and
above 850 mb much of the day. Winds toward the top of this
layer are progged near 50 kt, which gives an idea of peak gust
potential, with more frequent gusts around 40 kt likely thru the
afternoon. Thus, the Wind Advisory remains in effect regionwide
until 6 PM this evening. Still can`t rule out isolated gusts to
50kt today.
Winds should begin to ease just a bit this evening,though the
gusty west flow continues overnight as strong high pressure
slowly builds east from the Central US. Remaining dry tonight
with temps falling back into the teens and 20s. Wind chills
bottom out late tonight into the single digits.-- End Changed Discussion --
&&
.SHORT TERM /TUESDAY THROUGH TUESDAY NIGHT/...
Flow remains strong Tuesday as high pressure builds in from the west.
With the cold air mass entrenched, temperature anomalies run 10 to
15 degrees below normal. After a frigid start with morning
temps largely in the teens and wind chills near zero sets up an
afternoon likely a few degrees colder than the previous day,
with highs generally in the mid to upper 20s and wind chills in
the teens.
Dry conditions prevail with the building high under a mix of
mid level clouds and sunshine. WNW gusts 30 to 35 mph are
expected to persist thru the afternoon, gradually subsiding in
the evening and overnight.
&&
.LONG TERM /WEDNESDAY THROUGH SUNDAY/...
Key Points...
* Lowering chances of a significant winter storm in the Wed
night and Thursday timeframe.
* Remaining cold with temperatures running 5 to 10 degrees
below normal.
A 1050+ mb Arctic high continues to build in from the west
midweek, keeping the region dry to start the period. Though as a
baroclinic zone sets up over the South, low pressure develops
and deepens as shortwave energy swings through midweek. This low
is expected to trek east and eject off the Southeast coast
Wednesday night, passing to the south and east of the region
into Thursday, before exiting well out to sea.
Global guidance continues to trend farther south and east with
this system, lessening the potential of a significant snowfall
locally. While the threat has not entirely diminished, 00Z GEFS
run offers just 10% of members with a warning level (6 in+) snow
at KISP, and about half the members with at least an inch of
snow, lessening further going north and west. Tapered PoPs back
a bit in this period to align with forecast trend, but not
shutting the door entirely should the expected track shift a bit
closer over the next 48 to 72 hours.
The low passes out to sea regardless by late Thursday, and high
pressure returns once again from the west. This high remains west
of the area through much of the weekend, providing dry but cold
conditions.
&&
.AVIATION /15Z MONDAY THROUGH FRIDAY/...
-- Changed Discussion --
Deep low pressure over the Canadian Maritimes remains nearly
stationary as strong high pressure gradually builds from the
west.
BKN VFR cigs expected through much of the day today, with W
winds sustained 20 to 30 kt and gusts 35 to 45 kt, with
occasional gusts near 50 kt through this afternoon. Cigs
scatter and winds lighten a bit after sunset, but speeds remain
around 15-20G30kt on Tuesday.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
No unscheduled AMD expected.
Isolated gusts up to 50 kt possible thru this afternoon.
.OUTLOOK FOR 12Z TUESDAY THROUGH FRIDAY...
Tuesday: VFR. W winds G30 kt.
Wednesday: VFR.
Wednesday night: Chance of snow with MVFR or IFR vsby.
Thursday: Snow possible with MVFR/IFR cond. N-NW winds
G20-25kt, mainly afternoon/evening.
Friday: VFR. NW winds G20kt.
Detailed information, including hourly TAF wind component
forecasts, can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
Strong winds associated with deep low pressure centered over
the Canadian Maritimes persists in the near term.
For the ocean waters, Storm Warning remains in effect for the
ocean waters thru this afternoon. Thereafter, gales continue
through at least this evening, if not the overnight. Ocean seas
10 to 14 ft today gradually lower into this evening, but
remaining above 5 ft thru Tuesday night.
For non ocean waters, Gale Warning on the through this evening,
and through into early Tuesday morning for the eastern Long
Island Sound, and the eastern Long Island bays. Seas on the
Sound 5 to 7 ft today, and up to 5 ft possible on Tuesday before
lowering.
With cold air moving in, and the combination of strong winds
and high seas, there is also a chance of freezing spray late
tonight through Tuesday night. At this time, ice accretion is
expected to remain below Advisory criteria, but will continue to
monitor conditions should one be needed.
Wind gusts up to 25 kt likely continue on all waters into
Tuesday night before subsiding into early Wednesday, bringing a
return of sub SCA conditions that could persist into late week
depending on the track and strength of offshore low pressure
Thursday.
&&
.HYDROLOGY...
No hydrologic impacts are expected through this week.
&&
.TIDES/COASTAL FLOODING...
A long duration period of strong offshore westerly flow may
cause a few spots to experience low water conditions around the
times of low tide into Tuesday evening, mainly along Raritan
Bay, the north shore of Nassau and western Suffolk counties,
and possibly the bays of Long Island. Water levels are largely
expected to remain less than 2 ft below MLLW however, and a Low
Water Advisory appears less likely.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...Wind Advisory until 6 PM EST this evening for CTZ005>012.
NY...Wind Advisory until 6 PM EST this evening for NYZ067>075-
078>081-176>179.
NJ...Wind Advisory until 6 PM EST this evening for NJZ002-004-006-
103>108.
MARINE...Gale Warning until 6 AM EST Tuesday for ANZ331-332-335-338-340-
345.
Storm Warning until 4 PM EST this afternoon for ANZ350-353-355.
&&
$$
SYNOPSIS...DR
NEAR TERM...JC/DR
SHORT TERM...DR
LONG TERM...JP/DR
AVIATION...DR/MET
MARINE...DR
HYDROLOGY...DR
TIDES/COASTAL FLOODING...