912
FXUS61 KOKX 172145
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
545 PM EDT Mon Mar 17 2025
.SYNOPSIS...
High pressure builds in tonight and settles over the area Tuesday
and Tuesday night, remaining into Wednesday, then weakening early
Thursday as a cold front approaches. A low will develop along the
cold front as both of them pass over our area Thursday, exiting
northeast Friday into Friday night. Weak high pressure returns over
the weekend with another low impacting the region on Monday.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
-- Changed Discussion --
Fcst updated to expand the sca to all waters.
The only changes made with this early evening update were to
adjust dewpoints to better match the current trend of dewpoints
dropping west to east behind the exiting boundary. Other than
that, the forecast still remains on track.
Surface trough of low pressure with a wind shift to NW and dry
weather behind it will shift east of Montauk heading into this
evening. Dry weather otherwise for the night as high pressure builds
in behind the departing trough. The pressure gradient should be
strong enough to keep winds from decoupling from aloft, but cold air
advection should still allow overnight temperatures to fall into the
30s across the entire forecast area. Even some upper 20s anticipated
well NW of the city.-- End Changed Discussion --
&&
.SHORT TERM /6 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/...
Deep-layered ridging through the period with the surface ridge axis
over us by the end of the day. Resulting light boundary layer winds
are expected to allow for sea breeze development during the
afternoon, but late enough such that the higher side of guidance was
used for much of Long Island. Highs mostly in the upper 50s to lower
60s across the entire forecast area with sunny conditions and mixing
up to 925mb where temps are 6-8C.
With the surface ridge still overhead, light to calm winds and a
clear sky will lead to strong radiational cooling in the typical
spots away from the metropolitan area. Lows ranging from the mid 40s
in the city, to 25-30 in the Pine Barrens and spots across the
northernmost zones.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
Key Points:
* Above seasonal temps with sunshine Wed.
* A developing low along a cold front brings rain Thursday night
with a possible transition to snow on the back side of the system
in the interior.
* Gusty NW winds Fri-Fri Night.
* Dry and near-seasonal over the weekend.
* Uncertainty surrounds a low that could impact us on Monday.
A ridge is centered over the area to start Wednesday with surface
high pressure nosing in from the Canadian Maritimes. This high
pressure gradually weaken s through Wednesday night as the ridge
moves offshore in response to an approaching trough early Thursday.
A large part of Wednesday will be sunny before clouds start to
increase later in the afternoon and into the night as high pressure
gradually weakens. Highs will be above average in the under light
easterly flow in the morning that transitions to southeasterly flow
Wednesday afternoon and evening. Given the direction of the flow,
coastal locations will reach the low/mid-50s from cooler marine air
while interior locations that won`t get this air reach the low/mid-
60s. Lows Wednesday night will be somewhat moderated by
partly/mostly cloudy skies in the mid-40s to upper-30s.
Low pressure moves into the Great Lakes on Thursday and into Canada
Thursday night, dragging a cold front over the area Thursday night.
Low pressure will develop along the front over our area or just
before the front reaches our area, then tracking over the CWA,
depending on which model solution you are looking at. This
developing low is aided by a southern stream jet in which it
develops along the left exit region of the jet streak. Eventually
the deep trough over the Central-Eastern US moves over the area
Friday, leading the surface low to exit northeast towards the
Canadian Maritimes later Friday into Friday night.
With strong southerly flow prior to the low/front arrival, PWATs
should be maxed out around the time of the frontal passage between
0.8" to 1.10" which is around the 90th percentile and the max moving
average for this time of year based on SPC`s Sounding Climatology
Page. Since this coincides with the front, expecting numerous rain
showers with the front and developing low into Thursday night.
Eventually this rain will clear out with the exiting low Friday
morning, however, it may not be all rain. As the low exits
northeast, it deepens. This leads to an increasing pressure gradient
late Thursday night into Friday morning. This strong NW flow could
help colder air to advect in quicker on the back side of the low
leading to some snowfall in interior locations through mid-morning
Friday before precip gets shut off. Location of the low and timing
still vary a little in model guidance, so its hard to pinpoint
amounts at this time. But a trace to a few inches of snow look to be
reasonable to achieve late Thursday night into Friday morning in the
interior if the colder air filters in as expected. Total QPF amounts
currently look to range from 0.5" to 1.5". Not much more is expected
due to the progressive nature of the system.
As the low passes the area Thursday night winds increase early
Friday and remain strong through the day. They gradually taper
Friday night as the pressure gradient weakens. Expecting peak NW
winds on Friday to be 20-25 mph with gusts 35 to 45 mph. However,
its important to note that they could end up being slightly weaker
if the low does not deepen enough after exiting the region.
Highs Thursday will still be above average in the mid-50s to low-
60s. They cool into the low/mid-30s as a front passes Thursday
night. Friday will be colder as a result with highs in the low/mid-
40s.
Mainly zonal flow takes over into the weekend, staying dry. 12Z
guidance then diverges on a solution for another frontal system
which may impact us on Monday. Highs will mainly be in the 50s with
lows in the 30s to 40s.
&&
.AVIATION /22Z MONDAY THROUGH SATURDAY/...
A cold front and wave of low pressure to the east of the area
continues to track slowly eastward into Tuesday. Meanwhile, high
pressure to the west gradually builds through Tuesday.
Conditions were generally MVFR across the region, with local IFR
lingering until late afternoon east of the New York terminals.
Conditions will continue to slowly improve from west to east,
becoming VFR throughout by late evening. Timing of the improving
conditions may be off by an hour or so. Once VFR develops, VFR
continues through the remainder of the forecast.
Gusty NW winds around 15 kt, gust generally 20-25 kt, with a few
gusts up to 30 kt possible into this evening. Winds and gusts
diminish toward 12Z Tuesday, and back to W toward 18Z Tuesday.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Unscheduled AMD likely for timing of improving conditions through
this evening.
.OUTLOOK FOR 18Z TUESDAY THROUGH SATURDAY...
Tuesday afternoon through Wednesday: VFR.
Thursday: IFR/LIFR cigs possible in the morning mainly E of the NYC
metros, and MVFR to IFR NYC metros and W. Chance of showers late in
the day, and likely at night, with MVFR to IFR conditions.Snow
showers possible well inland late Thursday night. S winds 10-15 kt
with G20-25 kt, winds shifting W and NW during the evening into the
night.
Friday: MVFR, possibly IFR, with a chance of rain showers along the
coast, and snow/rain showers inland, ending west to east through the
day, and becoming VFR. NW wind 15-25 kt with G30-40kt, diminishing
at night.
Saturday: VFR.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90
&&
.MARINE...
-- Changed Discussion --
A sca for all waters until midnight, and on the ocean thru at
least Tue. The advisory has been extended on the ocean east of
Fire Island Inlet to include Tuesday night as seas remain
elevated due to a lingering swell. Meanwhile winds will be light
Tuesday and Tuesday night as a ridge of high pressure extends
through the area.
SCA criteria is not expected to be met Wed-Wed night.
On the ocean, waves will climb above 5 feet on Thursday, peaking at
8-9 feet Fri, eventually dropping below 5 feet Saturday afternoon.
Winds will reach SCA criteria late Thursday night through Friday
night, dropping below SCA levels Saturday. A period of gales is
possible on all waters Friday.-- End Changed Discussion --
&&
.HYDROLOGY...
There are currently no hydrologic concerns through the start of
next week.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory until midnight EDT tonight for ANZ331-332-
335-338-340-345.
Small Craft Advisory until 6 AM EDT Wednesday for ANZ350-353.
Small Craft Advisory until 6 PM EDT Tuesday for ANZ355.-- End Changed Discussion --
&&
$$
SYNOPSIS...JC/BR
NEAR TERM...JMC/JC/BR
SHORT TERM...JC
LONG TERM...BR
AVIATION...MET
MARINE...JMC/JC/BR
HYDROLOGY...JC/BR