okx-afd on 2025-02-23

724
FXUS61 KOKX 240004
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
704 PM EST Sun Feb 23 2025

.SYNOPSIS...
-- Changed Discussion --High pressure will be in place tonight, and slide east on
Monday. A weak cold front then moves through late Tuesday into
Tuesday night. Weak high pressure briefly returns Wednesday
before a quick moving frontal system affects the region
Wednesday night into Thursday. High pressure briefly returns
Friday into Friday night before a clipper system and cold front
moves through the northeast US next weekend.-- End Changed Discussion --

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
-- Changed Discussion --Mid level shortwave shifts through the region tonight, accompanied
by moisture centered around 500mb. Not enough moisture overall for
any precip, but it will leave us with a cloudy sky for most of
the overnight. This will also help limit radiational cooling in
spite of light to calm winds from a weak surface pressure
gradient. A brief window for radiational cooling towards
daybreak. Lows mostly 30-35 for coastal areas and lower to mid
20s inland and pine barrens of LI.-- End Changed Discussion --

.SHORT TERM /6 AM MONDAY MORNING THROUGH TUESDAY/...
High pressure will be centered off the Northeast coast on Monday.
This will set up a return southerly flow for the local area. Winds
arriving from the cold waters will hold high temperatures in the 40s
for most of the area, however some 50 degree readings are
anticipated in the urban corridor of NE NJ. Cirrus will begin to
filter in by late in the day after a sunny start.

Surface low pressure and a mid level shortwave pass well to our
north tonight, but there could be just enough moisture focused along
surface trough to trigger a shower late at night across the far NW
portion of the area with some PVA. Another shortwave then approaches
from the Ohio Valley on Tuesday and begins to shift through heading
into the evening. More low to mid level moisture will arrive with
this feature, and the surface trough nearby perhaps strengthens into
a weak cold front. This combination the moisture and lift then
brings a chance of showers to the entire area, with the better
overall chances north and west of the city.

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

* Temperatures will likely run 5 to 10 degrees above normal
Wednesday and Thursday. A return to more seasonable temps for
Fri/Sat, and possibly below normal to end the weekend.

* Mainly dry conditions are expected through mid week. A quick
moving frontal system will likely affect the region Wed Night into
Thursday.

Quasi-zonal upper flow to start the period with PAC jet riding the
northern tier of the CONUS around expansive polar trough across
southern Canada. Within this flow, a series of shortwaves will
traverse the northern tier of the US towards the region and
successively amplify eastern US troughing through the late week.

First shortwave of note (PAC origin), will eject from the Rockies
into northern plains Monday and through the region by Tuesday Night.
The result will be a quick moving and weak cold front passing east
Tuesday Night, with any light rain shower activity Tue aft/eve
coming to an end and a weak shot of caa.

Thereafter, increasing model agreement over the last 48hrs in
further longitudinal amplification of troughing across the eastern
1/2 of the US Thu/Fri in response to a phased PAC and polar
shortwave digging through the Central US Wed Night/Thu and into the
SE US Thu NIght/Fri. ECE and GEFS coming into better agreement with
the amplitude/timing of a neutrally tilted trough approaching the
east coast, before negatively tilting offshore. The deeper model
trend with this trough, with a bit of southern stream interaction,
does open the potential for a bit more moisture to be entrained into
the resultant frontal system, but overall limited QPF potential with
a progressive passage on Thu and WCB not getting going until east of
the region. GEFS, GEPS, ECE probs of 1/2" rain in 24 hours are all
20% or less at this point. If the trough trends towards a more
negative negative tilt orientation, would have potential for a
wetter solution than currently forecast, but low prob at this point.

Overall looking at a light rain rain event with the frontal system
approaching late Wed night and moving through the region Thu.
Unseasonably mild temps Wed Night and Thu in deep SSW flow ahead of
the cold front, although cloud cover and onshore flow will likely
hold temps in the 50s interior and 40s for south coasts.
Deterministic NBM looks reasonable and generally lies near the 75th
percentile of the ensemble cdf.

A shot of Canadian air, drying conditions, and return to more
seasonable temps Thu Night into Friday in wake of cold frontal
passage. Perhaps a few rain/snow showers Friday AM into early aft as
trough axis moves through.

General agreement in polar troughing exerting more influence on the
NE US for the second half of the weekend into early next week,
although there is inherent model spread and run to run inconsistency
at this time range on track/intensity of a resultant clipper system
tracking through southern Ontario/Quebec and northern New England on
Sat/Sat Night, and magnitude of polar intrusion in its wake. This
clipper system could bring the next chance for a limited rain/snow
threat, with a return to below normal temps likely during this time
period.-- End Changed Discussion --

.AVIATION /00Z MONDAY THROUGH FRIDAY/...
-- Changed Discussion --High pressure moves offshore into early Monday. A frontal
system then approaches from the west into Monday night.

VFR.

Winds will continue to diminish this evening, becoming light and
variable overnight into early Monday morning. Winds then begin
to increase out of the SE-S then S with speeds 10-12 kt by
afternoon. Winds veer slightly to the SSW Monday evening.

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

Timing of winds becoming SE-S on Monday may be off by 1-2 hours.

.OUTLOOK FOR 00Z TUESDAY THROUGH FRIDAY...

Monday Night: VFR.

Tuesday: Mainly VFR. Slight chance of showers and MVFR.

Wednesday: VFR.

Thursday: Showers and MVFR possible. S-SW winds G15-20kt in the
afternoon.

Friday: VFR. NW winds G15-20kt.

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

.MARINE...
The pressure gradient remains weak tonight through Monday with high
pressure in control. With the high moving offshore Monday into
Monday night, and with the approach of a weak cold front, southerly
winds will increase late Monday into Monday night. With warmer air
moving over the cold ocean waters during this time mixing will be
limited with gusts also limited, with gusts nearing 25 kt for a
brief period Monday night. A weak cold front crosses the waters late
Tuesday into Tuesday night with sub-advisory conditions continuing
through the period.

Next chance for SCA conds on the ocean late Wed Night into Thu with
strengthening SSW flow ahead of next approaching frontal system. SCA
ocean seas could linger through Friday in wake of frontal system.

.HYDROLOGY...
No hydrologic impacts are expected through the end of the week.

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

SYNOPSIS...JC/NV
NEAR TERM...JC/NV
SHORT TERM...JC
LONG TERM...NV
AVIATION...DS
MARINE...JC/NV
HYDROLOGY...JC/NV