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Area forecast discussion 
National Weather Service New York New York
133 am EDT sun Aug 28 2016

Synopsis...
high pressure builds across the tri-state area for this weekend.
A cold front will then approach the area Sunday night and slowly
move through on Monday. High pressure follows for Tuesday.
Another cold front moves through late Wednesday into Wednesday
night with high pressure for the end of the week.

&&

Near term /until 6 am this morning/...
the forecast is on track.

Deep layered ridging will allow for tranquil...dry and seasonable
temperatures tonight. Lows generally in the 60s...lower 70s for
NYC/NJ Metro...and some upper 50s across far outlying rural areas
with good radiational cooling.

&&

Short term /6 am this morning through Monday night/...
upper ridging flattens on Sunday...allowing a shortwave over the
northern plains today to slide towards the northeast US Sunday night.
At the surface...high pressure overhead early Sunday gradually
slides offshore...allowing a weakening cold front to approach
Sunday night and slowly cross on Monday.

Mostly sunny and dry conditions expected on Sunday...with light E/se
flow in the morning veering to the S/se. A Canadian maritime airmass
will limit temps to slightly above seasonable levels at the coast
in the lower 80s...while deeper mixing for NYC/NJ Metro and
particularly northwest interior should have temps in the to mid to upper
80s once again.

A moderate risk for rip current development exists on Sunday as 3
ft at 8 sec period swells build into the waters with minimal se/S
wind waves. There is a low potential for the risk to become high
late in the day if 2 ft 15+ second se swells begin to work into
the water from Gaston. With wna exhibiting a quick bias with
bringing in swells this Summer...and GFDL guidance slower to bring
in these swells...will hold to a moderate risk for Sunday.

Lagging forcing and weak elevated instability should limit
convective activity with the approaching cold front. Increasing
high and mid clouds expected...with an isolated shower or sprinkle
possible to survive into the region late Sunday night into Monday
morning. Cold front appears to only slowly sag through the area
Monday. Instability builds late Monday morning into Monday
afternoon with shortwave energy nearing...but downslope subsidence
and mid-level drying will likely be limiting factors for
convection. So only appears an isolated shra/tsra threat exists
with frontal passage...likely decreasing from NW to se during the
afternoon. Strong winds gusts would be main threat with any
thunderstorms based on drying low/mid levels.

Very warm temps expected on Monday with only gradual caa...downslope
flow and deep mixing...allowing temps to rise into the upper 80s to
lower 90s for much of the coastal plain...mid to upper 80s for NW
hills.

High risk for rip current development possible by Monday as long
period se swells from Gaston could build to 3 to 4 ft. If this
occurs...breaking surf in the 3 to 5 ft range could be expected
as well.

&&

Long term /Tuesday through Saturday/...
high pressure builds behind the departing cold front Monday night
into Tuesday before shifting offshore Tuesday night. This will keep
the region dry with temperatures around 5 degrees above normal.

A cold front approaches on Wednesday and passes during the late
day/nighttime period. Isolated to scattered showers and
thunderstorms are forecast during the period with the best overall
chance appearing to be during Wednesday night. There is a chance
that the cold front is still close enough, coupled with synoptic
lift from a jet streak aloft, for a chance of morning showers on
Thursday. For now, will go with slight chc pops east of the city
Thursday morning. Drying conditions otherwise through Saturday as
high pressure builds in behind the front. High temperatures Thursday
through Saturday will be fairly close to normal, and dewpoints all 3
days will allow for relatively comfortable conditions.

The threat for rough surf and high risk for rip current
development could continue mid to late week if se swells from
Gaston continue to affect the waters.

&&

Aviation /06z Sunday through Thursday/...
VFR with high pressure in control through this evening.

Light east-southeast-southeast winds expected at the NYC terminals, and
light/variable elsewhere through day break. Winds may briefly back
to the east after day break, but sea breeze flow will quickly take
over from late morning into early afternoon. Speeds will increase
to around 10 kt in the afternoon, strongest at the coast.

Winds diminish and veer to the SW tonight.

Outlook for 06z Monday through Thursday...
Monday...mainly VFR. An isolated afternoon shower or tstm
possible.
Tuesday...VFR.
Wednesday-Wednesday night...mainly VFR. A few showers or
thunderstorms possible.
Thursday...VFR. An isolated morning shower or tstm possible.

&&

Marine...
seas will slowly build into early next week in response to long
period swells being generated by distant tropical cyclone Gaston.
Refer to advisories from the NHC for latest forecast information.
Whether seas build to marginal sca levels Mon into Mon night will
be based on strengthening of Gaston.

For the rest of the forecast period, winds appear to remain below
advisory criteria, although they will increase during Wednesday
ahead of an approaching weak cold front. Seas will continue to
slowly build in response to long period swells being generated by
distant tropical cyclone Gaston. 5+ feet seas could move into to
the ocean waters as early as Monday night, and potentially linger
through the rest of the forecast period.

&&

Hydrology...
no significant widespread precipitation is expected through the
forecast period.

&&

Okx watches/warnings/advisories...
CT...none.
New York...none.
New Jersey...none.
Marine...none.

&&

$$
Synopsis...jc/NV
near term...NV/pw
short term...Nevada
long term...jc
aviation...ds
marine...jc/NV/pw
hydrology...jc/NV

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