424
FXUS61 KOKX 131938
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
338 PM EDT Sun Jul 13 2025

.SYNOPSIS...
Offshore high pressure departs further east tonight. A cold front
approaches the region from the west Monday, attempting to move
through into Monday night. The frontal boundary likely remains just
south of the area for a few days before returning north as a warm
front sometime late in the week. This will be followed but a cold
frontal passage late week into the weekend.

&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
High pressure that has been situated off the coast of Nova Scotia
exits further out into the Atlantic into tonight, as a cold front
over the eastern Great Lakes gradually works east.

Some clearing has worked in along much of the coast this
afternoon, with interior areas having a more difficult time,
though additional stratus develops and rolls in into this
evening. Lowered PoPs a bit across NE NJ and the LoHud Valley
late today with any activity likely remaining off to the west
based on current radar and latest hi res guidance. Still
possible a shower or spotty thunderstorm drifts east into this
evening, but coverage looks isolated at best with limited
forcing and most, if not all, remain dry through this evening.
Prefrontal convergence well ahead of an approaching frontal
boundary could instigate some showers into the western Lower
Hudson Valley overnight, but activity should weaken as it drifts
east.

With the persistent onshore flow and saturated low levels, in
addition to widespread stratus tonight, will have to watch for
possible areas of patchy fog or drizzle late, mainly LI and
southern CT.

&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/...
Ridge axis aloft shifts east of the region as a surface cold
front approaches from the west Monday, moving into the region
Monday night.

Any morning fog or drizzle comes to an end by mid morning,
and the stratus blanket attempts to break up into the afternoon.
The approach of the frontal system will eventually initiate
showers and thunderstorms, though forcing looks relatively weak
until later in the day. Looking at the thermo environment,
abundant moisture with a tropical like air mass in place and
PWATs progged near 2 inches will combine with modest instability,
though denser cloud cover could hinder this. Deep layer shear
will be lacking, with a piddly wind profile through much of the
column. This should keep convection relatively unorganized, but
can`t rule out a few strong or damaging wind gusts with any
thunderstorm, though the overall severe threat looks limited.

Perhaps a bit more of a concern is the potential for higher
rainfall rates in the moisture laden environment, particularly
for areas west of the Hudson. Hi res guidance, including the
12Z HREF, is signaling potential for pockets of convection
producing rates over an inch an hour, mainly over NE NJ and the
LoHud Valley. WPC has expanded the SLGT risk, in line with CSU
ML guidance, to now include northeast New Jersey and the Lower
Hudson Valley, with a MRGL for areas to the east. Certainly
could see localized to isolated flash flooding instances,
particularly in the SLGT risk area, but more likely areas of
minor nuisance flooding as the convection works through. Timing
looks mid to late afternoon at the earliest for western areas,
including NE NJ, NYC, and the LoHud Valley, before activity
works east across southern CT and Long Island into the evening
hours, and could linger into the overnight as the weakening
boundary slows or hangs up over the region, though rains should
lower at night.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
***Key Points***

*Potential remains for several days of high heat and humidity this
week. The higher confidence is now for Wednesday through Friday,
with widespread max heat index values forecast to be 95 to around
100 (Heat Advisory criteria).

*A relatively active pattern is expected with chances for several
days of afternoon showers and thunderstorms.

A frontal boundary will likely stall just offshore and linger near
the area through midweek before returning north as a warm front. A
cold front will then follow at the end of the week into the weekend.
Aloft, the pattern stays the same through the period. Although we
are under some high heights, we are somewhat on the eastern end of a
broad upper level trough centered over central Canada and few
shortwaves likely pass through.

With strong Bermuda high in place, a S/SW flow will allow plenty of
moisture to be sent our way. This combined with above normal high
temperatures brings some potential for a heat wave, with widespread
heat index values of 95 to around 100 (Heat Advisory criteria)
currently expected Wednesday through Friday. Temperatures have
trended down a bit, especially for Tuesday which now looks like it
may not reach Heat Advisory criteria. However, there still is
uncertainty especially given the potential for convection and slight
inconsistencies in a late week frontal system among the guidance.
The NBM was followed for highs but did manually lower afternoon
dewpoints a few degrees when better mixing is expected. This still
gave dewpoints in the lower to mid 70s.

Too early to talk specifics when it comes to severe or flooding
concerns with the aforementioned convection. These details will be
ironed over the next few days. There is plenty of moisture around
with pwats 1.50-2.00+ for much of the period so any convection that
does develop will likely be able to produce heavy downpours. As for
severe, while we are pretty unstable, shear looks weak through much
of the period, with some better values as we get into late week and
the weekend.

&&

.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
Weak offshore high pressure drifts east through tonight, and
remains offshore through Monday.

MVFR ceilings remain across much of the area, with VFR east of
the NYC terminals and into coastal Connecticut with a light southeast
to south flow. By around 19Z ceilings are expected to improve to
VFR at the NYC terminals. The improved conditions will be
short-lived as ceilings lower to MVFR during the early evening,
and then to IFR east of the NYC terminals late tonight. IFR
conditions are possible late tonight into early Monday morning
at the NYC metro terminals. Conditions improve to VFR around
midday or into Monday afternoon at all the terminals. There is
a lot of uncertainty with the timing of lowering conditions,
and areal extent of IFR, and possible LIFR. Patchy drizzle and
fog is also possible late tonight into early Monday morning.

Light SE winds up to 10kt this afternoon becoming generally
light and variable tonight. A more southerly flow develops
Monday with speeds to around 10kt.


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

Amendments expected due to changes in flight categories through
the forecast period with uncertainties of flight category
changes and timing.


.OUTLOOK FOR 18Z MONDAY THROUGH FRIDAY...

Monday afternoon: MVFR ceilings possible early afternoon, then
becoming VFR. MVFR possible in thunderstorms mid afternoon into
the evening. A chance of thunderstorms overnight. A few storms
could produce brief heavy rainfall late Monday afternoon into
the evening.

Tuesday-Friday: Mainly VFR. MVFR in showers or thunderstorms
each afternoon and evening.

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

&&

.MARINE...
Patchy dense fog is possible on the local coastal waters Monday
morning.

With a weak pressure gradient, winds and waves likely remain below
Small Craft Advisory criteria through the coming weekend. However,
a relatively active pattern is expected next week with chances
of afternoon showers and thunderstorms for several days. Winds
and waves will be higher in any storms.

&&

.HYDROLOGY...
Showers and thunderstorms move through Monday afternoon and
evening, and could produce locally heavy downpours with rainfall
rates that briefly exceed an inch per hour. This could lead to
areas of minor, nuisance flooding, with a localized flash flood
risk, especially across urbanized NE NJ.

At this time, there are no significant flood concerns Tuesday
through next weekend.

&&

.TIDES/COASTAL FLOODING...
For Atlantic Ocean beaches, the rip current risk today and
Monday is moderate with an onshore flow near 10 kt, a 3 ft swell
from the southeast at a 7 to 8 sec, and added onshore swells,
one of which is a long period swell.

&&

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

&&

$$

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