973
FXUS61 KOKX 170050
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
850 PM EDT Fri May 16 2025

.SYNOPSIS...
A warm front draped over portions of the Mid Atlantic lifts north
through the region tonight into early Saturday. An attendant cold
front follows, with the passage expected Saturday evening. A
secondary cold front passes Sunday night. Low pressure lingers in
New England and the Canadian Maritimes Sunday through Monday. High
pressure takes control Monday night into early Tuesday night.
Another frontal system impacts the area Wednesday into Thursday.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
Digging trough and upper low over the Upper Midwest swings east
across the Great Lakes region, sending an associated frontal
system toward the region. Warm front analyzed to the southwest
over the Mid Atlantic begins to approach and lift through
tonight.

With multiple spokes of vorticity rounding the trough, CAMs
have been signaling another MCS potentially developing well to
the west along a boundary tonight, before working east with the
outflow. Should this occur, it`s possible the remnants work
into the region overnight, though this is far from a guarantee,
and any local severe risk from this potential activity is low.
Otherwise, likely see areas of fog development once again into
the night with light flow and abundant surface moisture. The fog
may become locally dense depending on the evolution of any
convective system(s) to the west.

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
Upper level low and trough over the Great Lakes pivots east on
Saturday, as a vigorous shortwave tracks across the Mid Atlantic.
A warm front lifts thru by the morning, as the associated
surface low slides into Quebec. The attendant cold front looks
to move through locally in the early to mid evening.

A challenging convective forecast with uncertainty on timing and
coverage of any morning activity. The approaching cold front
adds more in the way of forcing as the day progresses, and
breaks in the clouds should develop by the afternoon. 12z HREF
is progging MLCAPE values as high as 1500 J/kg, along with bulk
shear values 30 to 40 kt. That said, cloud cover could limit
this instability, and subsidence behind any previous MCS could
help to cap the low levels as well. It now appears the core of
the shortwave energy passes north and west by mid afternoon,
and could help limit any organized severe threat locally. With
this, SPC has lowered their threat locally from a slight to a
marginal, which seems reasonable based on the above and
continued uncertainty.

CAMs aren`t overly aggressive in depicting convective
development, but should initiation occur, damaging wind gusts
would be the primary threat, though large hail and even an
isolated tornado cannot be ruled out in the environment.
Coverage looks isolated to scattered, especially across the
LoHud Valley and southern CT.

Cold frontal passage progged around 00Z Sun, and behind it winds
veer westerly into the overnight, with drying conditions
overnight as dew pts fall back into the lower 50s by daybreak.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
Key Messages:

 * Mainly quiet & pleasant weather Sunday through Tuesday.

 * A frontal system may will bring rainfall Wednesday, possibly into
   Thursday and Friday.

A surface low w/ an associated upper-level low will be located over
New England Sunday. This low will exit into the Canadian Maritimes
by Monday.

This low will bring a second cold front through on Sunday night
helping clear out partly to mostly cloud skies and advecting in
drier air. This leaves late Sunday night into Monday mostly
clear/sunny. A few showers are possible in the northern interior,
closer to the periphery of the low Sunday afternoon/evening, but
chances look quite low.

A quick moving shortwave will pass over or just to the north of the
area Monday afternoon/evening. This may lead to a few clouds, but
otherwise, we will remain clear and sunny late Sunday night through
most of Tuesday.

An increased pressure gradient from the low to our northeast will
lead to breezy W/NW flow Sunday and Monday. As the low exits farther
away, the gradient weakens, leaving light winds by Monday night. It
remains this way with high pressure at the surface through Tuesday.

12Z guidance still varies in timing and track of a frontal system
for the middle of next week. A low over TN/KY late Tuesday will
approach the area Tuesday night and pass near or to the south of the
area Wednesday into Thursday, pushing more north and/or east of the
area on Friday. This will bring a period of wet weather. There is
higher confidence in showers on Wednesday, but confidence is lower
Thursday and especially Friday and models diverge on a solution.

Sunday and Monday will see highs in the upper-60s to mid-70s, right
around the climatological average. Temperatures will be much cooler
from a passing frontal system on Wednesday with highs in the low-60s
under E/NE flow.

&&

.AVIATION /01Z SATURDAY THROUGH WEDNESDAY/...
A warm front moves partially through the area tonight then
advances further north on Saturday. A cold front follows for
Saturday evening.

Conditions lowering to IFR everywhere tonight, improving to MVFR
mid-morning Saturday, then VFR in the afternoon. PROB30 for TSRA
Saturday afternoon into early evening.

Southerly flow 5-10 kts expected through mid-morning Saturday,
then southerly winds pick up to 10-15 kt with some gusts up to
20 kt in the afternoon.


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

Timing of category changes could be off by a couple o hours.
Tempo or prevailing vsbys of 1/4sm possible at KJFK from 08-12z
Sat.


.OUTLOOK FOR 00Z SUNDAY THROUGH WEDNESDAY...

Saturday: Mainly VFR but MVFR possible in the afternoon with
chance of showers and thunderstorms with MVFR or lower conditions
possible.

Sunday: Mainly VFR. Slight chance of showers inland with MVFR
possible. W winds G20-25kt.

Monday - Tuesday: VFR. Monday NW winds G20-25kt day into evening.

Wednesday: MVFR or lower with showers likely, mainly at night. E
wind gusts 15-20 kt.

Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90

&&

.MARINE...
Areas of fog likely return tonight, potentially becoming dense
and persisting into mid Saturday morning. A Dense Fog Advisory
may be needed, with the potential for vsbys to fall to less than
1 nm at times overnight into Saturday AM.

Winds and waves remain below Small Craft Advisory (SCA) criteria
through at least Saturday night.

Sunday afternoon and evening, wind gusts may marginally reach SCA
criteria for the NY Harbor, western Sound and western Ocean.
Otherwise, sub SCA conditions are expected on all waters thereafter
through Wednesday. A passing frontal system will lead to ocean seas
climbing 5-7 feet Wednesday night through Thursday night.

&&

.HYDROLOGY...
Locally heavy downpours are possible with any thunderstorms
through Saturday aft/eve. While the overall flash flood threat
is low, the brief heavy rainfall could lead to minor nuisance
flooding in urban and poor drainage areas.

There are no other hydrologic concerns through the end of next
week.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...None.

&&

$$

AVIATION...JC/JM