713
FXUS61 KOKX 160801
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
401 AM EDT Mon Sep 16 2024

.SYNOPSIS...
High pressure remains in control through Monday night, before
gradually retreating north Tuesday into Tuesday night. A frontal
system slowly approaches from the southwest through mid- week
as high pressure drifts east in the northern Atlantic. Low
pressure may linger nearby Thursday along a cold front. A back
door cold front moves across Friday. High pressure from SE
Canada builds in for the weekend.

&&

.NEAR TERM /THROUGH TONIGHT/...
With deep layered ridging aloft and a large dome of high pressure at
the surface, expect the dry weather to continue with mainly sunny to
partly cloudy skies. The winds once again will be light and variable
to begin the day, but with solar insolation, the winds towards late
morning and mid day will become more ENE at around 5 to 10 mph.
Temperatures at seasonable levels for mid September.

For Monday night the upper level ridging begins to slowly break
down. More in the way of high clouds attempts to work in as low
pressure off the southeastern US coast begins to work NW. Partly
cloudy to mostly cloudy skies are expected Monday night with a
light E to NE flow remaining in place. With a bit more moisture
in the lower levels there should be a reasonable chance to see
some low stratus / patchy fog in many of the lower lying rural
locations like previous nights as of late. Temperatures should
average close to normal in outlying areas, and a bit above
normal in the more urban areas.

&&

.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
Surface high pressure will gradually begin to wane in strength on
Tuesday. A southerly component to the flow aloft begins to get
established during the afternoon as the region gets on the outer
edge of the northeast quadrant of a closed low getting into the
Lower Appalachians. The mid levels may moisten up enough to produce
more in the way of mid level clouds, especially as the day progress.
Thus a partly cloudy to mostly cloudy day from NE to SW across the
region appears most likely. With more mid and upper level clouds
compared to lower level clouds, expect the clouds to mainly filter
out varying amounts of sun. Temperatures will once again run right
around seasonable levels. Dew point readings should edge up in the
60s, especially along the coast as the day proceeds.

The high slowly drifts east through mid-week. At the same time, low
pressure over the Carolinas will slowly trek northwestward toward
the Ohio Valley through mid-week. The associated frontal system will
approach from the southwest and will begin to impact the region
Tuesday night.

The low and frontal system get caught under the upper level ridging
over the eastern US from mid to late week and a prolonged period of
some unsettled weather is possible as weak flow under the ridge will
mean slow movement of these features. Right now, it looks like the
most likely period of rain is overnight or early Wednesday morning
through Wednesday night. There is a deep moisture feed from the
tropics and training possible. Dew points rise well into the 60s
Wednesday into Thursday and PWATs around 2" are seen in most of the
guidance. Of course, this is all dependent on certain mesoscale
features that cannot be resolved at this point, but there is a low
chance right now of flooding, and the Weather Prediction Center has
placed the entire forecast area in a marginal risk of excessive
rainfall Wednesday into Thursday. With the previously mentioned
uncertainty, stuck close to the NBM and did not go any higher than
chance POPs through the long term. However, models have trended a
little slower on the systems arrival, so have kept Chance POPs out
of the forecast until 2am early Wednesday.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
Mid level trough remains over the region Thursday through Friday and
weakens Saturday. Mid level ridging eventually takes over to close
out the weekend.

At the surface, low pressure may still be not too far away to the
south of Long Island Thursday into Thursday night. Chances for
showers will remain in the forecast.

A back door cold front moves across Friday, keeping shower chances
in the forecast.  However POPs are more in slight chance range since
moisture becomes more limited as low to the south weakens and moves
farther away.

For Friday night into the weekend, dry conditions return as high
pressure builds in from the north. Clouds may very well linger
around to start but will be on a decreasing trend.

Temperatures favored the 50th NBM percentile as the pressure
gradient between low pressure to the south and high pressure to the
north remains, giving NE flow much of the time during the long term.
Gusty conditions expected along the coast as well. NBM 50th
percentile showed lower temperature for eastern half of the region
and along the coast compared to NBM. The temperatures are expected
to be below normal during the day.

&&

.AVIATION /08Z MONDAY THROUGH FRIDAY/...
High pressure will become centered off the New England
coast through early Tuesday.

VFR conditions are expected through much of the TAF period. Some
possible localized MVFR to IFR fog possible for KSWF and perhaps
some other inland terminals going into early this morning.

Winds will be under 10 kts with variable to easterly directions into
early this morning. For the rest of today, winds will be generally
SE near 7-10 kts before becoming lighter and more variable in
direction once again tonight.

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

Timing of SE winds development could be off by 1-2 hours.

MVFR to IFR stratus possible late tonight into early Tuesday
morning.

OUTLOOK FOR 08Z TUESDAY THROUGH FRIDAY...

Late Tonight through Tuesday: Chance of MVFR or lower conditions
with low clouds/fog late tonight into early Tuesday morning and
late Tuesday night, otherwise VFR.

Wednesday through Friday: Chance of showers with MVFR or lower
conditions possible especially with any low clouds/fog. ENE winds 10-
15kt G15-20kt, mainly at the coastal terminals during the day into
early eve.

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

&&

.MARINE...
Ocean seas may reach 4 to 5 ft by towards Tuesday morning into
evening, especially for the western ocean. 5 ft waves are expected
Tuesday night on the ocean waters. A SCA has been issued through 00Z
Wednesday. More widespread 5 ft waves on the ocean waters are
expected Wednesday on a persistent easterly flow.

SCA conditions are forecast on the ocean Thursday through Friday
night. Non-ocean waters initially remain below SCA thresholds
Thursday and Thursday night, but their wind gusts are forecast to
reach SCA levels for some portions at times Friday into Friday
night. There will be a persistent pressure gradient with low
pressure to the south of the region and high pressure to the north
of the region to maintain a gusty NE flow.+

&&

.HYDROLOGY...
No hydrologic through the forecast period. An extended period
of rain is possible from Tuesday night through Wednesday night
with a tropical feed and training possible. There is still some
uncertainty with regards to the amount of rain we may see. The
Weather Prediction Center has placed the southern portion of the
area under a marginal risk for excessive rainfall on Wednesday.
One factor against flooding would be the antecedent dry
conditions over the last week.

&&

.TIDES/COASTAL FLOODING...
With an approaching full moon on the 17th, astronomical high tides
will be rising into the first half of the week, with water levels
potentially rising through the week. Continuous easterly flow will
help build seas and allow for some piling of water. Winds are
expected to remain generally light, near 10 kt or less. While some
of the guidance is showing water levels increasing, there is a
general consensus of keeping them below minor coastal flooding
benchmarks for the most part, although Stevens suggest minor
benchmarks being reached for the south shore bays and for western LI
Sound locations towards late Tue / Wed. However, this will likely
depend on the development of low pressure off the Carolina coast and
its eventual track early next week.

There is a moderate risk of rip current development at the ocean
beaches Monday with an easterly flow developing, becoming high
risk on Tuesday.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory from 10 PM this evening to 8 PM EDT
     Tuesday for ANZ350-353-355.

&&

$$

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