653
FXUS61 KOKX 182140
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
540 PM EDT Fri Apr 18 2025

.SYNOPSIS...
A warm front moves north of the area tonight, with a cold front
moving through Saturday evening. High pressure builds over the
northeast Sunday into Monday. A frontal system then moves across
the region Monday night into Tuesday. High pressure returns for
Wednesday and Thursday with potential of another frontal system
for the end of next week.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
Subtle shortwaves swinging around the periphery of ridging
across the southeast were able to develop some sprinkles across
southeast CT. This activity has quickly pushed to the east. Have
increased sky cover a bit this evening based on latest satellite
trends. A sprinkle cannot be ruled out inland, but measurable
rain is not expected with a deep dry subcloud layer.

Otherwise, the pressure gradient remains tight over the area
tonight with high pressure shifting farther southeast offshore
and a low tracking to our north and west. The orientation of
these surface features will gradually shift the winds to more of
a SW/W direction. The area will become warm sectored overnight
with a warm front passing to the north. Clouds increase tonight
and winds stay up, so temperatures will not be able to drop too
much. Lows from NYC and north and west will bottom out in the
mid to upper 50s with Long Island and CT mainly in the lower
50s.

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH SUNDAY/...
Towards daybreak, some shortwave energy rounding the top of a
mid-level ridge will pass overhead. Some CAMs are hinting at
some showers across the interior. Thinking the 12z HRRR is way
too aggressive and went more in line with the 12z ARW for PoPs
Saturday morning.

Aforementioned low pressure to our north will continue moving east
and drag a cold front toward the area. Out ahead of the front, deep
SW/W flow through the layer will help the area warm up. The NBM
deterministic temperature guidance continues to trend upward while
still falling at or below the NBM25th percentile for MaxT. Given the
anomalous warm air mass and the upward trending NBM have bumped up
MaxTs a few degrees. Used a blend of the previous forecast, the
NBM90th, the HRRR and bias corrected guidance. One concern though is
the amount of cloud cover that will be around. This may cause
highs to end up a few degrees low than forecast.

With the warm, moist airmass ahead of the cold front, the area looks
to become marginally unstable. MLCAPE values look to max out around
500J/kg, mainly across the interior. Some convective activity looks
to fire up along the approaching cold front/pre frontal trough and
move into our area. The activity is forecast to enter the Lower
Hudson Valley area around 5 to 7 pm. The thinking right now is any
of this earlier activity would be able to produce lighting with some
of the CAPE profile getting into the -10 to -20 layer. Forecast
soundings show a decrease in CAPE at this level after 8pm, so went
only showers after that. At this time, no organized severe
convection is expected.

The cold front moves through Saturday night and then high pressure
builds in through Sunday. Cooler and drier air mass filters in
and temperatures will be back down in the 60s.

&&

.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
There has been little change to the overall forecast thinking in
the long term and have stuck close to the previous forecast/NBM.

Deep layered ridging will be in place Sunday night and gradually
slide east of the area by late Monday. A progressive shortwave and
associated frontal system will then move across the region Monday
night into Tuesday. The warm front will lift to our north early
Tuesday with the trailing cold front passage likely occurring
Tuesday afternoon and evening. The shortwave lifts over southeast
Canada Tuesday night into Wednesday leaving behind a SW flow aloft.
There were some hints at another shortwave for Thursday in previous
model cycles. However, the latest guidance has shifted towards
ridging, which potentially could last through the end of the week.

For sensible weather, mainly dry conditions are expected with the
highest probabilities of showers occurring Monday night into Tuesday
morning with the aforementioned warm front. The trailing cold front
appears to have limited moisture and lift to work with so it likely
comes through dry Tuesday afternoon and evening. Have left in low
probabilities (20-30 percent) Thursday night into Friday, consistent
with the NBM. However, it is very possible these probabilities are
adjusted down if ridging ends up persisting for the rest of the
week, similar to much of the 12z guidance.

Temperatures on Monday will likely be the coolest for this period
due to onshore flow from retreating high pressure. Highs will be a
bit below normal in the upper 50s to around 60 degrees. Temperatures
for the rest of the week look to range from the middle 60s to lower
70s, warmest away from the immediate coast.

&&

.AVIATION /22Z FRIDAY THROUGH WEDNESDAY/...
A warm frontal passage occurs tngt. A cold front approaches late Sat
aftn.

VFR thru at least 18Z Sat, then there is a chc for MVFR in isold-sct
shwrs mainly aft 22Z. A prob30 was included for the shwrs, but due
to high uncertainty was kept VFR for now.

If the activity does develop close to 21-23Z, there could also be
some isold tstms particularly KSWF.

Strong S winds into this eve. Winds decrease aft 23Z, then veer to
the WSW thru 12Z Sat. Increasing WSW winds thru the day on Sat.

LLWS tngt with wind speeds 45-50kt at 2kft, ending aft 12Z Sat.

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

Wind direction and speed at KEWR more uncertain than usual thru 00Z
with sea breeze flow opposing S flow. Amendments have been made to
better adjust timing, but further amendments are possible.

.OUTLOOK FOR 18Z SATURDAY THROUGH WEDNESDAY...

Saturday: Mainly VFR. Slight chance of showers aft 20Z. SW winds
gusting to around 30kt.

Sunday: VFR. NW wind gusts 15-20kt possible.

Monday: VFR, then sub VFR possible at night with a chance of showers.

Tuesday: Becoming VFR with W winds.

Wednesday: VFR.

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

&&

.MARINE...
Small Craft Advisories in effect on all waters tonight except
the western and central Sound and Peconic and Gardiners Bays.
Once nearshore gusts pick up Saturday morning then those areas
will be added to the Advisory. Additionally, all non-ocean
waters tonight could see a lull in wind gusts.

SCA conditions gradually lower Saturday night, with some 5-7ft
seas lingering in the ocean zones. Conditions will then remain
below SCA levels Sunday night through the middle of next week
with a relatively weak pressure gradient over the waters.

&&

.FIRE WEATHER...
SPS for CT and NY remains in effect until 7 PM this evening.
Although still windy Saturday, RH will be higher so not
expecting any headlines. Continue to exercise caution handling
any potential ignition sources, including machinery, cigarettes,
and matches. Any fires that ignite will have the potential to
spread quickly.

&&

.HYDROLOGY...
There are no hydrologic issues through next week.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory from 8 AM to 8 PM EDT Saturday for ANZ331-
     332-340.
     Small Craft Advisory until 8 PM EDT Saturday for ANZ335-338-
     345.
     Small Craft Advisory until 8 AM EDT Sunday for ANZ350-353.
     Small Craft Advisory until 8 AM EDT Sunday for ANZ355.

&&

$$

SYNOPSIS...DS/JT
NEAR TERM...DS/JT
SHORT TERM...JT
LONG TERM...DS
AVIATION...JMC
MARINE...DS/JT
FIRE WEATHER...
HYDROLOGY...DS/JT