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Area forecast discussion 
National Weather Service New York New York
742 am EDT Thursday Sep 3 2015

Synopsis...
a cold front approaches from the north and passes through late in
the day into tonight. High pressure builds down from southeastern
Canada overnight into Friday and remains in control through early
next week. A cold front then moves through the region during the
middle of next week.

&&

Near term /until 6 PM this evening/...
some areas of morning fog has developed across outlying
areas...with some patchy dense fog possibly reducing visibility to 1/4
mile across parts of Suffolk County. Coverage is not enough to
warrant a dense fog advisory. Fog will burn off through the
morning as temperatures rise.

Otherwise...a warm and humid day with highs around 90 in/around
NYC and in the middle to upper 80s elsewhere. Surface dewpoints will be
in the middle 60s...but there should not be any heat advisory issues.
Maximum heat index may come close to 95 across NYC and parts of NE New Jersey.

An approaching cold front late then combines with sufficient cape
and just enough moisture for low chances of showers and
thunderstorms this afternoon.

&&

Short term /6 PM this evening through 6 PM Friday/...
the cold front eventually pushes south of the County Warning Area tonight with
low chances of showers/thunderstorms again this evening. A trailing
shortwave pushing south then keeps a slight chance of showers for
some sections during the overnight hours. The shortwave exits to
the SW with an isolated shower still possible Friday morning for
primarily NE New Jersey and the city. Negative vorticity advection...
surface ridging and subsidence should then keep the entire County Warning Area dry
during the afternoon. Models are however showing some lingering
middle level moisture...so some areas could remain mostly cloudy
through the afternoon...primarily southwestern zones. A mav/NAM
MOS blend looked good for high temperatures and should be 7-10
degrees cooler than today's in most cases.

Although minimum humidity levels should be in the 50s...gusty
east winds Friday afternoon may pose a enhanced concern for spread
of brush fires due to 400-500 kbdi values and available fine
fuels. Along the coast...the potential exists for a high rip
current risk late in the day due to easterly winds and wind waves.

&&

Long term /Friday night through Wednesday/...
gradually increasing drought and fire weather concerns through the
period.

High pressure...both at the surface and aloft...builds over the East
Coast this weekend with the center of the high passing through New
England. With low pressure developing over the southeast U.S. Coast...a
tightening east to northeast gradient will develop over the tri-
state area for Saturday...and then winds shift to more of a
southerly flow for Sunday as the high moves offshore.

Temperatures on Saturday will be right around normal...topping off in the
upper 70s to around 80. With warm air advection underway for
Sunday...highs will climb into the middle and upper 80s.

Bermuda high pressure then strengthens along the East Coast with
increasing heat and humidity for the start of the new week. Highs on
Monday and Tuesday will top off in the middle to upper 80s...and
possibly around 90 for NYC and NE New Jersey. Surface dewpoints will also rise
into the low to middle 60s for much of the area and in the middle to upper
60s for Long Island and southeast CT.

The ridge along the coast breaks down and moves offshore late
Tuesday/Tuesday night...and then a cold front approaches on
Wednesday and moves through during the middle to the end of next
week.

&&

Aviation /12z Thursday through Monday/...
a cold front approaches from the north this morning...then crosses
the area this afternoon and evening. High pressure then builds
down from southeastern Canada into Friday morning.

Mainly VFR through the taf period. Expect IFR fog at kisp and MVFR
fog at kswf/kgon to dissipate by around 14z. Haze aloft is
possible at the city terminals early this morning as well. There
is a low chance for isolated-scattered showers/thunderstorms this afternoon
and evening mainly to the north/west of city terminals. At this time
confidence in timing/occurrence is too low to place in tafs.

Light and variable winds will give way to a north-NE flow under 10 knots
at city terminals by middle-late morning and at kteb/kswf by early
afternoon. Seabreeze likely at CT terminals this morning...and
probable at kjfk/kisp by early afternoon and at klga/kewr/khpn by
late afternoon. Seabreeze is also possible at kteb but confidence
is too low to reflect in tafs. Winds become light and variable
throughout again this evening. NE winds at under 10 knots develop
overnight.

... Metropolitan enhanced aviation weather support...

Detailed information...including hourly taf wind component forecasts
can be found at: http://www.Erh.NOAA.Gov/zny/n90 (lower case)

Kjfk fcster comments: timing of changes in wind speed and
direction could be off +/- 2-3 hours. Moderate-high confidence in
occurrence of seabreeze. Low-moderate confidence in timing of
seabreeze.

Klga fcster comments: timing of changes in wind speed and
direction could be off +/- 2-3 hours. Moderate confidence in
occurrence of seabreeze. Low-moderate confidence in timing of
seabreeze.

Kewr fcster comments: timing of changes in wind speed and
direction could be off +/- 2-3 hours. Moderate confidence in
occurrence of seabreeze. Low-moderate confidence in timing of
seabreeze.

The afternoon kewr haze potential forecast is yellow...which
implies
slant range visibility 4-6sm outside of cloud.

Kteb fcster comments: timing of changes in wind speed and
direction could be off +/- 2-3 hours. Moderate confidence in
occurrence of seabreeze. Low-moderate confidence in timing of
seabreeze. There is a very low chance of a shower or
thunderstorm this afternoon and/or evening.

Khpn fcster comments: timing of changes in wind speed and
direction could be off +/- 2-3 hours. Moderate confidence in
occurrence of seabreeze. Low-moderate confidence in timing of
seabreeze. There is a very low chance of a shower or thunderstorm
this afternoon and/or evening.

Kisp fcster comments: timing of changes in wind speed and
direction could be off +/- 2-3 hours. Moderate-high confidence in
occurrence of seabreeze. Low-moderate confidence in timing of
seabreeze. Timing of end of IFR and of MVFR this morning could be
off +/- 1-2 hours.

Outlook for 12z Friday through Monday...
Friday...mainly VFR. Isolated shower/thunderstorm possible
mainly to the west of city terminals into Friday afternoon. NE-east
winds g15-20kt possible.
Friday night...VFR. East-NE winds g15-20kt possible.
Saturday-Monday...VFR.

&&

Marine...
relatively tranquil conditions for today and this evening with a
weak surface pressure gradient remaining in place. Winds then pick
up late tonight into Friday as high pressure builds down from the
north...tightening the pressure gradient. There could be a few
gusts up to 25 knots over the ocean waters by late afternoon...and
seas could rise to 5 feet by evening as well over the eastern ocean
waters. Models have trended a little weaker and later with
increasing winds...plus wavewatch has delayed the onset of 5 feet
seas for the past couple of runs. Add to this that would be a late
third-period event...will therefore hold off on Small Craft Advisory issuance for
now and let the day shift see if trends continue and issue Small Craft Advisory as
necessary.

A tight east to northeast gradient remains over the waters on
Saturday...and wind gusts to 25 knots along with 4-6 feet seas are likely
on the ocean waters before conditions gradually subside Saturday
night.

With high pressure over the waters for the start of the new
week...conditions will remain below Small Craft Advisory criteria.

&&

Hydrology...
no widespread significant rainfall is forecast today through the
middle of next week. Drought will continue to develop region wide.
Long Island and southern CT are currently experiencing moderate
drought conditions.

&&

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

&&

$$

Synopsis...jc/mps
near term...mps/jc
short term...jc
long term...mps
aviation...maloit
marine...jc/mps
hydrology...jc/mps

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