Area Forecast Discussion
Issued by NWS Upton, NY

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160
FXUS61 KOKX 170808
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
408 AM EDT Tue Jun 17 2025

.SYNOPSIS...
High pressure weakens further today and shifts to the east. A warm
front approaches late tonight and moves through likely sometime
early Wednesday. A cold front then moves through Thursday
evening/night. High pressure builds in Friday, and generally
dominates into the beginning of next week. A warm front will lift
to the north and west of the region Saturday night into Sunday.

&&

.NEAR TERM /THROUGH TONIGHT/...
High pressure that has been nosing into northeastern portions of the
area weakens further today and shifts east. The stalled frontal
boundary that is well to our south will start to drift north as a
warm front. No big change in heights aloft, we remain on the eastern
periphery of a broad trough. Several weak embedded disturbances will
pass overhead today into tonight.

Plenty of cloud cover expected again today with rounds of scattered
shower activity. Continues to be a difficult PoP forecast given weak
lift. With the aforementioned disturbances aloft have more
confidence in CAMs today and stuck close to this guidance.

Temperatures overachieved Monday even with showers and cloud cover
so stuck with NBM today given the similar flow. This gives highs in
the upper 60s to low 70s. Also stuck with NBM for lows with thick
cloud cover expected resulting in a lack of radiational cooling, 60s
across the area.

&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY NIGHT/...
An active short term period is expected. A warm front moves through
early Wednesday morning with a cold front following Thursday
evening/night. The train of embedded upper level disturbances
also continues. This pattern will result in several rounds of
showers with potential for thunderstorms as well.

Heavy showers and thunderstorms early Wednesday morning, mainly for
NYC and north and west: Early Wednesday morning a warm front will
push through and continue the surge of warm moist air into our area.
Pwats increase to over 2 inches, which is near the daily record for
the OKX upper air sounding. With the passing of the warm front the
some CAMS show a shower/thunderstorm activity. Exact coverage is
difficult to know at this point, but any shower or thunderstorm that
does develop should be able to produce heavy downpours. CAPE is
elevated but has a tall and skinny shape. It is worth noting that
the GFS has stronger mid-level capping and is likely resulting in
the lack of modeled QPF.

Heavy showers and potential for strong thunderstorms Wednesday
afternoon, mainly for areas west of eastern LI and eastern CT:
With the area warm sectored we should be able to destabilize to
about 1000 J/kg of MLCAPE or more in northeast NJ and the Lower
Hudson Valley. A surface trough and shortwave aloft should be
able to trigger some afternoon shower and thunderstorm activity.
Decent instability but once again the profile is tall and skinny
and shear is not too strong. This limits the severe threat and
may be more of a heavy downpour threat, but some stronger cells
could produce sub-severe wind gusts.

Potential for severe thunderstorms Thursday evening: Thursday
continues to be highlighted as a potential severe thunderstorm day
by the CSU-MLP with a 15-30% chance of damaging wind gusts. The
SPC has also outlined the area in a slight risk. The area is
able to destabilize again ahead of an approaching cold front
with guidance consensus around 1000 to 2000 J/kg of MLCAPE. The
triggers for this event will be more focused and stronger than
Wednesday given the falling heights aloft and cold front. The
reason for severe potential comes from a more favorable CAPE
profile and stronger shear than Wednesday.

Aside from the shower and thunderstorm activity in the short term,
the warming temperature trend will continue with temperatures in the
upper 80s to lower 90s on Thursday. Did end up with slightly lower
heat indices because Tds were lowered given the expected mixing
and NBM high bias. Still have Tds in the upper 60s.

&&

.LONG TERM /FRIDAY THROUGH MONDAY/...
Key point:

* Potential for high heat and humidity Sunday into early next week.

Global models are in good agreement and forecast largely followed
NBM during this period.

In the wake of a cold frontal passage Thursday, high temperatures
for Friday and Saturday will be a few degrees cooler than Thursday,
and dew points will be much lower. Temperatures will be near normal
to near 5 degrees above normal.
With high pressure centered off the southeast coast Friday into the
beginning of next week, heat and humidity will be building.
Maintained slight chance probabilities across the region for
Saturday night with the potential for showers and thunderstorms to
move over the building ridge, and with a weak shortwave and a warm
frontal passage to the northwest and north. The ridge and heights
build Sunday into Monday, and the ridge remains into Tuesday. With
NBM deterministic high temperatures Saturday into next week near the
25th percentile and the potential for higher temperatures, have
blended in a small percentage of the 75th percentile, resulting in
highs a couple of degrees above the NBM deterministic. The heat and
humidity increase Sunday into Tuesday with temperatures 10 to 15
degrees above normal. There is the potential for reaching heat
advisory criteria Sunday and Monday across northeastern New Jersey,
the lower Hudson Valley, New York City, much of southern Connecticut
and into northern Nassau and northwestern Suffolk counties. And a
few places across northeastern New Jersey into the lower Hudson
Valley may be near warning levels, however, this will depend on dew
points in the upper 60s to lower 70s, which may mix out during the
afternoon.

&&

.AVIATION /08Z TUESDAY THROUGH SATURDAY/...
High pressure off the New England gradually weakens and shifts east
today as a stationary front remains well to the south. The front
will begin lifting north as a warm front late tonight.

IFR to LIFR prevails through the overnight and into this morning,
and possibly into the afternoon, as any gradual improvement to MVFR
will likely be during the afternoon. The improvement will be brief,
and conditions are expected to lower once again to IFR and LIFR
during this evening.

Scattered light rain or drizzle will be possible through the
overnight as another area of precipitation approaches northern New
Jersey at 07Z. The chances for additional showers increases this
evening, mainly north and west of the NYC metro.

Winds will generally be E to NE 10kt or less through the overnight
and into this morning. Winds then become ESE-SE late morning into
the afternoon, and remain under 10kt.


 ...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty... Amendments
expected for flight categories through Tuesday night.

Timing of LIFR may be off by several hours overnight Thursday gets
quite a bit more interesting with the cold front moving into the
area during the afternoon and evening hours. Moderate to high
instability and a strengthening vertical wind profile suggest the
potential for strong to severe bowing line segments. SPC Day 4 and
CSU-MLP have the area in greater than 15% for severe weather with
the main threat being damaging winds. Limiting factors could be too
much dry air in the low- levels, lowering MLCAPE values. However, it
is a bit early to be too specific with details, but nevertheless
something to keep a watch on. In addition, temperatures will be
about 10 degrees above normal with dew points well into the 60s to
around 70. NBM box and whisker plots show deterministic NBM at or
below the 25th percentile. Thus, there is the potential for higher
temps. Deterministic NBM similar to long rage GFS and ECMWF MOS
values and could linger a few hours longer than indicated this
morning.


.OUTLOOK FOR 06Z WEDNESDAY THROUGH SATURDAY...

Late Tuesday night: IFR-LIFR, in stratus and fog. Showers, mainly
northwest. A chance of an isolated thunderstorm toward Wednesday
morning.

Wednesday: Chance of IFR early, then becoming MVFR during the
afternoon. Brief VFR possible. Showers and thunderstorms likely with
MVFR.

Thursday: VFR. Showers and thunderstorms with MVFR possible in the
afternoon and evening. A gusty thunderstorm possible across
northeastern New Jersey into New York City.

Friday and Saturday: VFR.

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

&&

.MARINE...
Winds and seas remain below Small Craft Advisory criteria through
Wednesday night. A S/SW flow then increases and some 25 kt gusts are
possible by Thursday afternoon. Especially nearshore gusts. Seas
also likely increase to 4-5 ft across the ocean waters.

With a strong SW to W flow in the wake of a cold front ocean seas
will be near 5 feet Friday into Friday evening. Winds  gradually
diminish late Friday into Friday evening as high pressure builds
toward the waters, and ocean seas fall below 5 feet by late Friday
night. Winds and seas then remain below SCA levels Saturday into
Saturday night.

&&

.HYDROLOGY...
Locally heavy downpours are possible with any showers/thunderstorms
Wednesday morning, Wednesday afternoon and again Thursday
afternoon into the evening. However, the risk of flooding will
be mitigated by the speed of any cells and lack of overall cell
training.

No hydrologic impacts expected thereafter through the beginning
of next week.

&&

.TIDES/COASTAL FLOODING...
Rip current risk remains moderate today and Wednesday with a
continued E/SE 3ft 7s wave component and parallel/onshore flow.

&&

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

&&

$$

SYNOPSIS...MET/JT
NEAR TERM...JT
SHORT TERM...JT
LONG TERM...MET
AVIATION...MET
MARINE...MET/JT
HYDROLOGY...MET/JT
TIDES/COASTAL FLOODING...JT