361
FXUS61 KOKX 230821
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
421 AM EDT Wed Jul 23 2025
.SYNOPSIS...
High pressure moves offshore today but remains in control through
early Friday. A cold front moves through the area Friday evening
into Friday night, with another frontal system possibly impacting
the area for later in the weekend.
&&
.NEAR TERM /THROUGH TONIGHT/...
Heights aloft steadily rise today as an upper level ridge builds in.
The axis passes through at the very end of the tonight period, with
500mb heights maxing out around 594dam. At the surface, high
pressure shifts offshore today and a return flow starts to kick in.
These features will lead to dry and mostly sunny conditions.
The airmass is still on the cooler side from what we have seen a
lot this summer so highs will top out in the low to mid 80s,
actually right around normal for this time of year. The pressure
gradient tightens a bit late in the day resulting in a S/SW
flow picking up. Overnight lows will be much warmer than last
night given higher winds and increasing moisture, low 60s
across the interior and low 70s along the coastal areas.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
Hot and humid conditions are expected during the short term
period.
The upper level ridge axis will already be to our east Thursday
morning and a broad trough will approach and gradually lower
heights. At the surface, high pressure holds its ground offshore
and really remains in control through Friday morning. However,
the pressure gradient over the area strengthens further and will
lead to a gusty southwesterly flow. Moisture continues to
increase, but with some mixing expected in the afternoon
dewpoints could drop a bit. Due to this, went a bit lower than
NBM with dewpoints. Combination of low 90s high temps and mid to
upper 60s dewpoints will result in spotty max heat indices
right around 95 for northeast NJ and portions of the Lower
Hudson Valley. Since it will likely be isolated, have held off
with the issuance of a Heat Advisory. Other locations look to
fall short of Advisory criteria.
The flow weakens just a bit on Friday but stays pretty gusty.
Higher heat and humidity is leading to widespread forecast max
heat index values at Warning criteria (105 degrees) in some
locations. However, there is a bit of uncertainty given the
potential for clouds and convection. The higher chances of
Warning criteria look to be across northeast NJ, NYC, western
LI, southern Lower Hudson Valley and portions of western CT. A
Watch may be needed if confidence continues to increase. Other
locations look to reach Advisory criteria, except for southeast
Suffolk and southern New London counties.
As for the aforementioned convection, a cold front approaches
during the day and passes through likely sometime during the evening
or early night. Out ahead of the front, the environment should
be able to destabilize well. There is some disagreement from the
NAM and GFS as to how much MLCAPE will be available, but it is
too early for specifics anyway. Consensus however does show
about 25 to 30 kts of 0-6km bulk shear. It looks like there is
at least potential right now for some of these storms to reach
levels. One limiting factor to note that is already being seen
in the forecast soundings is a relatively skinnier CAPE hinting
at weaker updrafts. Another one is a weaker shortwave aloft.
Regardless of severe or not, showers and thunderstorms are
possible across the whole area.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
The NBM was largely followed with this update with no major changes.
**Key Messages**
* Hot and humid conditions continue into Saturday with heat indices
potentially in the mid/upper 90s Saturday.
* Showers/thunderstorms are possible from Sunday into Monday.
Saturday is a bit more uncertain with respect to the excessive heat
given any lingering cloud cover in the morning. h850 temperatures do
tick a few degrees down, resulting in highs in the mid and upper
80s, yielding heat indices potentially in the mid and upper 90s.
Heat headlines may be needed on Saturday should the current
temperature and dewpoint forecasts hold.
&&
.AVIATION /09Z WEDNESDAY THROUGH SUNDAY/...
-- Changed Discussion --
High pressure moves offshore today, and remains offshore into
Thursday.
VFR through the forecast period.
Light and variable winds become S up to 10 kt today, and up to
15 kt at KJFK with sea breeze enhancement. A few gusts up to 20
kt are possible this afternoon, however, not confident enough
in frequency and occurrence to include in the TAFs at this time.
Winds become light SW to light and variable tonight.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
A few gusts up to 20 kt possible this afternoon.
.OUTLOOK FOR 06Z THURSDAY THROUGH SUNDAY...
Late Wednesday night: VFR.
Thursday: VFR. South winds G20-25kt, highest at the coast.
Friday: VFR likely through morning, possibly followed by periods of
sub VFR in showers and thunderstorms for the afternoon and
evening. Southwest winds G15-20kt.
Saturday: VFR with scattered showers and thunderstorms during the
afternoon and at night.
Sunday: Mainly VFR. MVFR or lower possible in any showers or
thunderstorms.
Detailed information, including hourly TAF wind component
forecasts, can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
Sub Small Craft Advisory conditions expected for the most part
through early next week.
Brief 25 kt gusts are possible in a southwesterly flow on Thursday,
mainly on the ocean waters. Gusts look to get close to 25 kts on
Friday ahead of a cold frontal passage.
Showers and thunderstorms are possible ahead of the cold frontal
passage Friday afternoon through the evening. There is potential for
some of these to be severe.
&&
.HYDROLOGY...
There are no hydrologic concerns through early next week at this
time.
&&
.TIDES/COASTAL FLOODING...
The rip current risk for today has been upgraded to moderate with a
but of a stronger southerly flow forecast. The moderate was kept for
Thursday, but there is potential for a high rip current risk to be
needed with forecast winds also increasing.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...None.
&&
$$
SYNOPSIS...DS/JT
NEAR TERM...JT
SHORT TERM...JT
LONG TERM...DS/JT
AVIATION...MET
MARINE...DS/JT
HYDROLOGY...DS/JT
TIDES/COASTAL FLOODING...