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Area forecast discussion 
National Weather Service New York New York
426 am EDT sun Aug 30 2015

Synopsis...
high pressure remains just offshore today ahead of an approaching
trough which will cross the area tonight. Low pressure then
passes to the north across eastern Canada on Monday...sending a
weak back door cold front through the area Tuesday morning. High
pressure will remain in control for the remainder of the week.

&&

Near term /until 6 PM this evening/...
the trend will be for warmer and increasingly more humid
conditions heading into the new week as a high amplitude ridge
over the western U.S. Merges with the sub tropical ridge along
the eastern Seaboard. In between...a weakness across the middle
section of the country will gradually fill...while a northern
stream short wave trough passes through the area tonight. At the
surface...this will be reflected as a surface trough or warm front...
preceded by weak thermal forcing. This forcing combined with
marginal instability may be enough for an isolated shower and/or
thunderstorm this aft/eve...mainly north and west of NYC. Clouds
will also spread in from the northwest today with mostly cloudy
conditions by afternoon inland and party sunny at the coast.

Highs will range from the lower 80s near the coast...to around 90
inland,

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

&&

Short term /6 PM this evening through Tuesday night/...
aforementioned trough/warm front moves through tonight with gradual
clearing from northwest to southeast by morning. The upper level ridge begins to
expand eastward on Monday with warming temperature profiles aloft and a
gusty west/SW flow in the after. This will allow for highs a few
degrees warmer than on sun...with readings topping out in the
lower 90s inland.

A weak back door cold front then passes through Monday night as low
pressure passes well to the north and east across the Canadian
Maritimes. Not much relief though for Tuesday with perhaps a degree
or two shaved off of Monday highs. Lows will range from the lower to
middle 60s inland...to 70 to 75 NYC metropolitan. These readings are still
well above normal. It will also be muggy with dew points well into
the 60s. Heat index values look to remain below advisory criteria
at this time.

Winds briefly go northwest Tuesday morning behind the cold front...but then
return from the S by after as the front lifts northward and dissipates
nearby. Subsidence aloft will put a cap on any convection during
this time period.

&&

Long term /Wednesday through Saturday/...
the main theme of the long term period will be the continuation of
heat and humidity across the region.

Models are in good agreement with the 500 mb pattern across North
America into the middle of the week as an upper level ridge
out west merges with the sub tropopause ridge over the western Atlantic.
This will result in dry and unseasonably warm weather through Thursday
possibly Friday. This will depend on the timing of the next cold
front moving across which is currently uncertain due to
differences that develop in the 500 mb flow during the latter portion
of the week. Could see a few showers or thunderstorms with the frontal
passage which is currently slated for Friday...followed by dry
conditions and cooler but still above normal temperatures for the
weekend.

Highs will generally range in the upper 80s to lower 90s across the
area through much of the week...the exception Friday/Sat with the
frontal boundaries in/through the area. Heat indices are expected
to be close to the ambient air temperature and are not currently expected
to reach 95 degrees in NYC through Wednesday.

&&

Aviation /08z Sunday through Thursday/...
high pressure slides offshore. A trough of low pressure crosses the
area late today into tonight.

VFR conditions are forecast through the taf period.

A west/SW flow 5 to 10 knots is forecast this morning. Sea breezes
develop this afternoon with speeds 10 to 15 knots. A few gusts to 20
knots are possible at NYC terminals as well.

An isolated shower or thunderstorm cannot be ruled out northwest of NYC
terminals this afternoon.

Winds veer to the SW tonight 5 to 10 knots.

Outlook for 06z Monday through Thursday...
Sunday night-Thursday...VFR. Afternoon seabreezes at coastal
terminals each day. SW gusts to 20 knots near city terminals possible
Monday afternoon.



&&

Marine...
a relatively quiet period with sub-Small Craft Advisory conditions will feature
late after/early evening enhancement of the SW flow from the New York bight
east along the ocean waters. These winds may gusts to around 20
knots with seas as high as 4 feet. High pressure will then build
across the waters on Tuesday with tranquil conditions through Thursday.

&&

Hydrology...
no significant rainfall is forecast through the upcoming week.

&&

Tides/coastal flooding...
with a recent full moon...brief minor inundation is possible
during the times of high tide across the typically vulnerable
coastal locales into the start of the work week.

&&

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

&&

$$

Synopsis...dw
near term...dw
short term...dw
long term...24/dw
aviation...ds
marine...24/dw
hydrology...dw
tides/coastal flooding...//

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