745
FXUS61 KOKX 131955
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
355 PM EDT Fri Jun 13 2025
.SYNOPSIS...
A frontal wave will pass to the south late tonight into Saturday.
Behind it, high pressure builds in from the northeast Saturday
night into Sunday. Weak high pressure will be in place through
Wednesday, with a warm front lifting north through the area by
Thursday, followed by a cold front Thursday night.
&&
.NEAR TERM /THROUGH SATURDAY/...
A confluent flow between the northern and southern branches of
the polar jet will be featured across the Northeast. This will
allow high pressure to build across eastern Canada and into the
Northeast. To the south across the northern Mid Atlantic
states, a frontal wave will move offshore late tonight into
Saturday, passing south of the area. The latter of which will
bring showers areawide tonight and a possible thunderstorm,but
mainly after midnight into Saturday morning. There will be some
elevated instability, but mainly across the southern half of the
forecast area. With PW values approaching 2 inches, any embedded
convection could produce brief heavy rainfall. Otherwise, the
system is rather disjointed and will transition to some light
rain by Saturday afternoon. High pressure and drying conditions
will work in from the north as high pressure builds behind the
departing low.
Expected rainfall amounts late tonight into Saturday will be
between 0.25 and 0.50 inches. Stayed close to an NBM/WPC
consenus. Right now, not buying into some of the higher amounts
shown by the 12Z Canadian and ECMWF. 13Z NBM 50th percentile is
0.3 to 0.4", with the mean a bit higher (skewed toward higher
amounts). However, probability of greater than 0.75" is only
15-25%.
Overnight lows will be in the upper 50s to lowers 60s, which is
nearly normal. However. due to the cloud cover, northeast flow,
and rain, highs on Saturday will likely not climb out of the
60s. This is more than 10 degrees below normal.
&&
.SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY/...
High pressure noses in from the northeast Saturday night into
Sunday with only a slight chance of light rain during this time.
Model time height cross sections during this time show dry mid
levels with moisture confined to the low levels, mainly below
700mb. In fact, while the forecast remains mostly cloudy during
this time, it could very well remain dry through Father`s Day
and temperatures may be on the upper end of the guidance.
For the time, expect lows in 50s Saturday night and highs in the
60s for Sunday. This is on the cool side.
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
A relatively zonal upper flow is anticipated through Wednesday night
before it amplifies with a trough axis approaching Thursday night
and passing through on Friday. This leads to weak surface high
pressure over the region with a stalled boundary to our south. This
boundary then becomes a warm front and advances north by Thursday
with weak ridging aloft. A cold front then follows during Thursday
night or possibly on Friday.
Highest chance of rainfall within the long term appears to be with
the cold front passage, but there`s uncertainty surrounding how
probable it will be due to timing differences for the passage among
the global models. A passage during the daytime Friday would
probably bring a higher threat overall with a greater chance of
heavy downpours as instability would be higher during the daytime.
12z LREF leans toward the faster side of the guidance envelope with
the h5 trough axis and attendant cold front. The cold front is
therefore more likely to pass through during Thursday night,
mitigating the potential for severe weather and flooding impacts.
With that said, trends need to be watched so see if the frontal
passage becomes more likely during the daytime on Thursday, or at
the least, a prefrontal trough acting as a focus for convection.
NBM was used for temperatures through the long term period.
Thursday`s high temperatures however may eventually need to be
raised by at least 5 degrees given the progged h8 temperatures, but
with the aforementioned convective uncertainty, have not adjusted
from the NBM at this time. Heat impacts may factor in for some
locations if it ends up being hotter than currently forecast,
particularly away from the coast.
&&
.AVIATION /20Z FRIDAY THROUGH WEDNESDAY/...
A cold front will remain stalled south of the region as an area of
low pressure develops and approaches along the front. The low exits
towards the tail end of the TAF period.
VFR conditions expected through this evening and a portion of the
overnight. MVFR is expected to hold off for the first half of the
night, with higher chances late in the overnight mainly towards and
after 08-09z and carrying into Saturday morning. Chances for showers
increase late tonight, becoming likely early Saturday morning. The
chances for IFR increase into Saturday morning, except for northern
most terminals where MVFR is expected to prevail.
E to SE winds this afternoon around 10 kts, followed by the winds
going more easterly tonight. The winds then become more
northeasterly Saturday. The winds decrease to near 5 to 8 kts
tonight into early Saturday but will be variable in direction for
some terminals outside of NYC. The winds increase closer to 10 kt at
most terminals during by midday.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Amendments may be needed later tonight into Saturday morning for
changing flight categories.
.OUTLOOK FOR 18Z SATURDAY THROUGH WEDNESDAY...
Saturday afternoon: MVFR and IFR with chance of showers. Occasional
NE wind gusts 15-20 kt possible.
Saturday night: Lowering chances of showers. MVFR to IFR possible.
Sunday: Chance of showers. Slight chance of a thunderstorm afternoon
into early evening. MVFR to IFR possible at times. Otherwise VFR.
Monday: Chance of showers. MVFR to IFR possible at times. Otherwise
VFR.
Tuesday: Mainly VFR.
Wednesday: Mostly VFR, with the chance of a period of sub-VFR.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90
&&
.MARINE...
Sub advisory conditions are anticipated for all waters through the
first half of the weekend. Ocean seas generally hold at 2 to 4
ft with a relaxed pressure gradient and a light onshore flow.
Marginal SCA seas are possible for the central and eastern ocean
zones late Saturday night into Sunday morning.
Sub-advisory conditions should otherwise continue through
Wednesday.
&&
.HYDROLOGY...
No hydrologic impacts expected through early next week.
Next chance for impacts would be Thursday into Thursday night with
any thunderstorms that manage to develop in a moist airmass in
place. There`s high uncertainty this far out in time regarding the
probability, timing and magnitude of any impacts with this.
&&
.TIDES/COASTAL FLOODING...
The rip current risk is low for the rest of today with a light
easterly flow and limited swell. There is a moderate rip current
risk on Saturday with an east to southeast swell.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...Air Quality Alert until 11 PM EDT this evening for NJZ002-004-
006-103>108.
MARINE...None.
&&
$$
SYNOPSIS...JC/DW
NEAR TERM...DW
SHORT TERM...DW
LONG TERM...JC
AVIATION...JE
MARINE...JC/DW
HYDROLOGY...JC/DW
TIDES/COASTAL FLOODING...
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