Area Forecast Discussion
Issued by NWS Upton, NY

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311
FXUS61 KOKX 171130
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
730 AM EDT Tue Sep 17 2024

.SYNOPSIS...
High pressure gradually moves farther off the New England coast
through midweek with low pressure slowly approaching from the south.
The low lingers nearby Thursday before shifting slowly farther away
Thursday night. Low pressure may linger just offshore to the
south Friday and Saturday before high pressure builds in from
the northeast Sunday through Tuesday.

&&

.NEAR TERM /THROUGH TONIGHT/...
Some patchy fog along with low clouds this morning. Expecting
the fog to dissipate by mid to late this morning. Temperatures
and dewpoints exhibit little difference between observed and
forecast values. Forecast overall is on track.

Over the course of today and tonight, high pressure will be moving
farther away from New England and farther out into the Atlantic.

The surface pressure over the local area will be decreasing over
this time period. Simultaneously, an increase in the pressure
gradient develops between high pressure farther offshore and low
pressure to the south. This will result in an increasing easterly
low level flow.

This will make for more clouds, a cooler boundary layer and less of
a diurnal temperature range. The forecast high temperatures for
today are a blend of the MET and MAV MOS. For tonight, with more
clouds and low level easterly winds, using the relatively
warmer MAV guidance.

&&

.SHORT TERM /WEDNESDAY THROUGH THURSDAY/...
Low pressure approaches from the south Wednesday into Thursday
and then slowly drifts farther away Thursday night. Chances for
rain increase during the day. Easterly low level flow
continues. Consensus of raw temperatures for high temperatures,
as the temperatures will likely be below MOS. Cloudy conditions,
rain, gusty easterly winds will not allow for much warming
during the day.

For Wednesday night, low pressure slows down offshore, slightly
strengthens with rain more likely. Will once again use the consensus
of raw temperatures for low temperatures Wednesday night to convey a
less vast range of temperatures. Not expecting temperatures to
decrease that much with overcast conditions, chances for rain, and
breezy easterly winds in the forecast.

Low will still be close enough offshore to keep a chance of
showers for Thursday. Used the Superblend for max temperatures,
keeping cooler than NBM.

Rain overall not expected to be heavy with generally light
rainfall amounts. There will not be much in the way of vertical
forcing or enhancements as the upper trough exhibits no
significant changes.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
Friday into early next week, global guidance shows a deepening
trough over the western ATlantic just off the northeast coast with a
growing ridge over the Ohio River Valley and Great Lakes region. At
the surface, a low will linger off the coast to our south on Friday
and Saturday before getting nudged out by high pressure building in
from the surface to the north and northeast.

Rain chances could continue Friday into Saturday. While global
guidance varies in positioning of the low, scattered to isolated
showers are possible, with the best chances in southern areas of the
CWA. Cloud cover will likely be persistent from the nearby low until
high pressure builds in stronger by Sunday. A dry forecast will
likely take over on Sunday into Tuesday with high pressure building
in. With disagreement in the models, its important to note that some
things could still change.

Temperatures in the long-term will likely stay mild and slightly
cooler than seasonal averages due to a persistent NE flow. Highs on
Friday and Saturday will be in the mid/low-70s dropping to the low-
70s to upper-60s Sunday and Monday. Given the stronger pressure
gradient both aloft and at the surface from opposing low and high
pressure, winds may be breezy at times through the long-term period,
primarily after Saturday morning.

&&

.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
High pressure will remain centered off the New England coast through
Tuesday with low pressure to our south into Wednesday.

IFR to MVFR ceilings in the early morning with less persistent low
ceilings west of NYC. Occasional LIFR has been observed.
Visibility will likely be okay at most terminals. Conditions
should improve by 12Z-15Z, becoming VFR. MVFR/IFR is likely again
tonight across the area with occasional LIFR possible. Unlike
today, lower categories may persist into the afternoon tomorrow.

Winds are light and variable across much of the area, or with a
light E/NE flow. They become SE 5-10 kts this afternoon. Winds
turn easterly early tonight dropping to near 5 kts, then
gradually increase through the rest of the night and remain
easterly, becoming 10-15 kts.

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

Amendments possible for ceiling and visibility changes until 12-15Z.

OUTLOOK FOR 12Z WEDNESDAY THROUGH SATURDAY...

Wednesday and Thursday: Chance of showers with MVFR or lower
conditions. ENE winds 10-15G20kt on Wed, mainly at the coastal
terminals.

Friday: VFR. Chance of showers. NE winds G15-20kt.

Saturday: VFR. NE winds 15-20G25kt, especially near the coast.

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

&&

.MARINE...
SCA conditions expected on the ocean waters through Wednesday,
SCA in effect for the ocean zones. Non-ocean waters remain below
SCA thresholds. For wind gusts, some non-ocean waters could
briefly gust to near SCA thresholds through Thursday. Ocean
waters likely remain at SCA levels Wednesday night and Thursday.

Seas may fluctuate at times between 4 and 5 ft late Thursday into
Friday. A NE wind is expected throughout and could gust close to 25
kt toward Friday. More widespread 25+ kt wind gusts are more likely
toward Friday night and may stick around into the weekend.

&&

.HYDROLOGY...
No hydrologic concerns with showers Wednesday through Thursday.
Rainfall amounts less than a half inch. Locally higher amounts
possible.

There are no hydrologic concerns for the long-term period.

&&

.TIDES/COASTAL FLOODING...
Minor coastal flooding remains a possibility, if not a
likelihood for portions of the coast for the mid to late week
period. The chances for widespread minor coastal flooding
increase with a northeast wind and potential piling of water
water at some coastal gauges. A few locations may reach moderate
coastal flood benchmarks, especially for the western south
shore bays later in the week.

There will be a high rip current risk for ocean beaches today.
A high rip current risk is expected for all ocean beaches on
Wednesday as well. Ocean seas are building during this time
period to 5 to 6 ft with onshore winds of near 10 kt.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...High Risk for Rip Currents through this evening for NYZ075-080-081-
     178-179.
NJ...None.
MARINE...Small Craft Advisory until 6 PM EDT Wednesday for ANZ350-353-
     355.

&&

$$

SYNOPSIS...JM/BR
NEAR TERM...JM
SHORT TERM...JM
LONG TERM...BR
AVIATION...BR
MARINE...JM/BR
HYDROLOGY...JM/BR
TIDES/COASTAL FLOODING...