NYC Office Forecast Discussion

000
FXUS61 KOKX 150030
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
830 PM EDT Tue Jul 14 2020

.SYNOPSIS...
A back door cold front will pass through the area tonight. High
pressure then builds in for mid week. The next frontal system
will affect the region late Thursday through Friday night.
High pressure will build in for the upcoming weekend. Another
frontal system may impact the region for the beginning of next
week.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
Showers and thunderstorms ahead of a back door cold front have
begun to weaken. Updated probabilities for current trends.

The upper low along the New England coast will work offshore
tonight, while a back door cold front drops NE to SW across the
area overnight. At the same time, an upper ridge over the Ohio
Valley and Great Lakes builds east.

Skies will generally be mostly clear the first half of the
night with some wraparound clouds dropping south across New
England and into the area by daybreak.

Overnight lows will be nearly seasonable, in the 60s most places
to around 70 across the NYC metro.

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/...
An upper ridge builds across the area during this time, while
surface high pressure over the Canadian maritimes builds
southward across the area.

Models continue to show low-level moisture gradually working in
beneath the subsidence inversion around 85h on Wednesday and
then lower level moisture at night with an E/SE flow. Thus,
skies will likely vary with partly sunny skies tomorrow to
possibly becoming mostly cloudy at night.

Highs on Wednesday will be in the upper 70s to lower 80s, with
lows in the 60s. This is near or slightly below normal.

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

&&

.LONG TERM /THURSDAY THROUGH TUESDAY/...
A sub tropical ridge along the eastern seaboard will be moving
into the western Atlantic during Thursday as a trough across
central Canada moves slowly to the east. A weak shortwave will
be moving into the region along with a developing warm front.
There have been some timing differences in how quickly this wave
will move into the region, and the trend has been to slow down
the movement. While there may be minimal chances for
precipitation into the far western zones Thursday afternoon, the
better chances now are Thursday night into Friday. The wave
weakens Friday night as a boundary sinks to the south of the
area.

The sub tropical ridge becomes reestablished Saturday and
Sunday, and extends into eastern Canada. With the strong ridge
in place a weak shortwave moving through the flow Sunday will
dampen, and remain mainly to the north, having little impact for
the area. A deep return flow with the ridge in place will bring
above normal temperatures for the upcoming weekend, along with
increased humidity levels. Guidance temperatures and dew points
are now a little higher than previous guidance, and heat indices
Saturday through Monday will range in the mid to upper 90s. A
frontal boundary moving into the region Monday and Tuesday may
affect high temperatures for Monday. And any storms that develop
may be more across the northern tier, along the northern
periphery of the ridge. A weak trough remains into Tuesday along
with a surface frontal boundary. And with energy moving through
the flow chances of precipitation will remain Tuesday.

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

&&

.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
A backdoor cold front will cross the area overnight, followed
by high pressure building in for Wednesday.

Some showers and thunderstorms continue to move across some of
the terminals, mainly east of NYC. There is a showers
approaching KTEB, which is weakening. Unsure if this cell will
impact any of the other terminals. Showers should only continue
for another hour or so.

Otherwise, mainly VFR through the TAF period. There is a chance
of MVFR ceilings tonight into early Wednesday morning, but
think if these occur they are likely to be confined to far
eastern terminals.

Winds initially are from the west across NYC and point west. To
the east, an outflow boundary has caused winds to become
easterly, mainly from a line from KHVN to KFOK. This boundary is
moving from east to west. This boundary will gradually dissipate
as it move west and the sun sets. As a back door cold front move
across the area overnight, winds will shift to the north
everywhere. Winds then turn more easterly and southeasterly
during the day Wednesday. Speeds will remain around 10kt or
less.

.OUTLOOK FOR 00Z THURSDAY THROUGH SUNDAY...
.Wednesday night...Mainly VFR. Low chance of MVFR cigs.
.Thursday...VFR.
.Thursday night-Friday night...Chance of SHRA/TSRA with MVFR or
lower conditions.
.Saturday and Sunday...VFR.

&&

.MARINE...
Finally, a period where seas have gone below 5 ft on the ocean
after a prolonged SE swell. Tranquil conditions are forecast on
the waters as high pressure builds in late tonight into
Wednesday.

A frontal system impacts the waters Thursday night into Friday night
with the chance of thunderstorms. High pressure returns Saturday and
Sunday, and then another frontal system impacts the area Monday.
Winds and seas are expected to remain below SCA levels across the
forecast waters Thursday through the upcoming weekend. With a
prolonged southwest flow, that strengthens Monday, gusts and seas on
the ocean waters may reach small craft levels.

&&

.HYDROLOGY...
No significant hydrologic impacts forecast during the period.

&&

.EQUIPMENT...
NYC NOAA Weather Radio Station KWO35 (162.55 MHz) is undergoing
its final stages of testing, and is operating at full power.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...None.

&&

$$
SYNOPSIS...MET/DW
NEAR TERM...MET/DW
SHORT TERM...DW
LONG TERM...MET
AVIATION...BC
MARINE...MET/DW
HYDROLOGY...MET/DW
EQUIPMENT...

NWS OKX Office Area Forecast Discussion