National Weather Service National Headquarters

• Home
• Site Map
• News
• Organization
• Search for: NWS All NOAA 

-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KOKX 191503
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
1103 AM EDT Sun Aug 19 2018

.SYNOPSIS...
A cold front south of Long Island will continue to slowly sink
into the Mid Atlantic region today as a wave of low pressure
travels along it. A high pressure ridge will extend southwest
from New England Monday into Tuesday while weak low pressure
passes to the south. A cold front will move across on Wednesday,
followed by high pressure to close the week.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Frontal boundary to our south will continue to sink a little
farther south today. Low-mid level NVA is pushing south through
the tri-state area, and this has allowed the northern half of
the area to dry out. Will go with a dry weather forecast with
partial sunshine here (CT and most of the Lower Hudson Valley)
and low chances of light rain or drizzle along with a mostly
cloudy sky elsewhere.

NE flow and cloud cover will hold high temperatures to mostly
70-75.

There is a moderate risk for the development of rip currents at
the ocean beaches today.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH TUESDAY/...
The upper trough will be slow to depart the northeast tonight
and Monday due to downstream ridging. Thus have maintained low
pops tonight through Mon morning. By Mon aftn, the trough should
be far enough east with enough subsidence from a ridge of high
pres extending through New England to keep conds dry. Waves of
low pres will continue to pass to the south through Mon night,
but are expected to be far enough south to not impact the local
area.

A frontal system will then approach the area on Tuesday with
increasing chances for rain returning during the aftn.

There is a moderate risk of rip current development on Monday.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
With the approach/passage of a more significant upper trough
and associated cold front Tue night into Wed, will see likely
PoP late Tue night and possibly into Wed morning. See Hydrology
section for further details, as there could be some urban and
flash flood potential, impacting the Wed AM rush if current
model timing holds.

With mid level confluence behind this departing trough on Thu and
then ridging aloft Fri into Sat, sfc high pressure should then
follow, with a noticeably drier air mass moving in on Thu with
dewpoints in the 50s and remaining into Saturday.

Except for Tue night/Wed when temps may be a few deg above avg,
expect temps right near seasonal averages.

&&

.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
A weak frontal boundary will remain stationary across the Mid
Atlantic states today, while high pressure noses in from the
north.

MVFR cigs will continue through the afternoon, but indications
that a periods of VFR cigs are possible late this afternoon into
tonight as drier air works down from the north. Conditions then
may fall back down to mvfr late tonight, particularly across
coastal terminals.

Light shra and drizzle activity will be most prevalent along
NYC/NJ metro and LI terminals through this afternoon, with
activity diminishing this evening.

Gusty NE flow will continue for NYC terminals and points east
through this afternoon, subsiding a bit tonight. NE winds along
the coast likely still maintain around 10 kt.

.OUTLOOK FOR 12Z MONDAY THROUGH THURSDAY...
.Mon-Tue...Improvement to VFR on Monday, remaining VFR through
Tuesday.
.Tue Night-Wed...Chance of shower/tstm with MVFR conditions.
.Thu...VFR.

&&

.MARINE...
SCA for LI Sound and the eastern bays has been cancelled given
the obs for the past few hours with gusts being held only
around 5 kt above sustained winds, and the expectation that
sustained winds probably don`t increase much into early
afternoon before diminishing later this afternoon.

Otherwise, a tighter pressure gradient will maintain SCA
conditions on the ocean waters today and continue into Monday.
Marginal SCA wind gusts are likely for the remainder of near
shore waters.

Then, sub-SCA conditions are expected for all the forecast waters
early into the middle of next week. Ocean seas could reach SCA
criteria again Wednesday night into Thursday.

Ocean seas out east may build to SCA levels of at least 5 ft on Wed
ahead of an approaching cold front. These elevated seas may linger
into Wed night.

&&

.HYDROLOGY...
No hydrologic impacts are expected through Tue.

Tuesday Night into Wednesday...Showers/tstms with heavy rain
may be possible with a passing frontal system. With low areal
FFG especially over NE NJ, PW increasing to well over 2 inches,
and deep layer SW flow indicative of potential training of
cells, there is some urban and flash flood potential in this
time frame from NYC north/west.

&&

.EQUIPMENT...
NYC NOAA Weather Radio Station KWO-35 (162.55 MHz) remains off
the air for an extended period of time.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory until 2 PM EDT Monday for ANZ350-353-355.

&&

$$
SYNOPSIS...
NEAR TERM/MARINE...JC
AVIATION...NV