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Area forecast discussion 
National Weather Service New York New York
745 am EDT Thursday Oct 30 2014

high pressure builds over the area through tonight. Low pressure
develops off the middle Atlantic coast Friday. ..then tracks
northeast to east of Cape Cod by Saturday evening. Meanwhile a
secondary low forms off the middle-Atlantic coast Saturday...then
tracks northeast to the Canadian maritime provinces by Sunday
evening. High pressure builds in behind this storm through Monday
night...then moves offshore on Tuesday. A warm front crosses the
area Tuesday night...followed by a cold front approaching on


Near term /until 6 PM this evening/...
made minor changes this update to reflect the latest trends in
observations and guidance. Exception is the temperature at
fok...which has fallen quite a bit more than expected. Overall
though...the forecast appears on track.

Patchy fog...locally dense...mainly over the higher elevations to
the west/north of NYC appearing to have started to dissipate
and as of now...looks to be on track to become at most isolated in
nature by at this time do not plan on re-issuing Special Weather Statement for
locally dense fog at 11z.

Otherwise...passage of 700-500 hpa trough axis today will only
produce some scattered clouds as around 10kt or downslope boundary layer
flow serves as a limiting factor.

For highs today used a blend of mav/met/ecs guidance with NAM
2-meter temperatures and a mix down from 900-875 hpa per BUFKIT
soundings. Expect highs to be near to slightly below normal.


Short term /6 PM this evening through 6 PM Friday/...
a 850-500 hpa shortwave ridge crosses the area tonight...with
associated subsidence promoting minimal cloud cover and
diminishing winds. As a result...have trended towards lower of
met/mav/ecs guidance and NAM 2-meter temperatures for lows. Not
quite certain enough of a completely clear sky and light winds to
go colder at this time. Lows should be near to slightly below

A weak inverted trough extends north-northwest from coastal low developing off
the Virginia/NC coast Friday towards Long Island. This coupled with a
passing weak 700-500 hpa shortwave warrants increasing cloud cover
over the entire region and slight chance probability of precipitation for -shra over
mainly Long Island Friday afternoon.

For highs Friday...a blend of mav/met/ecs guidance with NAM
2-meter temperatures and a mix down from 900-875 hpa per BUFKIT
soundings. Highs should be around 5 degrees below normal.


Long term /Friday night through Wednesday/...
a strong shortwave energizes a surface low emerging off the
Carolina coast late Friday night. Model consensus and their
respective ensemble means strengthen this storm as it heads
NE...passing southeast of the 40n/70w benchmark late Saturday night into
Sunday morning. A surface trough first brings a chance of showers
to the area Friday night. At least chance probability of precipitation remain on Saturday
with some middle level lift...although model quantitative precipitation forecast output suggests
that coastal areas warrant likely probability of precipitation...being closer to the
storm center. Chances of rainfall then diminish through Saturday
night as the storm shifts farther out to sea...with dry weather
by Sunday morning.

Thermal profiles suggest an all rain event. By the time freezing
levels and wet bulb zeroes lower enough to support a mix of rain
and snow...precipitation will have ended or will just about to
end. This would be the case for elevations above 1000 feet north
and west of the city. With such limited coverage of a low
probability event...have removed the mention of snow from the

Winds will end up being the bigger story...and will be at their
strongest from Saturday afternoon through Sunday afternoon. Could
get close to Wind Advisory criteria at some point during this will need to keep an eye on this.

With high pressure in control...Sunday through Tuesday is
expected to be dry. Highs on Sunday averaging at least 10 degrees
below normal...with wind chill values around 30 degrees for the
first half of the morning. The growing season then probably ends
for more of the zones outside of the city Sunday night with lows
around the freezing mark. Temperatures then begin their climb back
towards normal on Monday...before reaching near normal on Tuesday
with a SW flow.

Next chance of showers then arrives Tuesday night into Wednesday
with a warm front passage followed by the approach of a cold
front on Wednesday.


Aviation /12z Thursday through Monday/...
hi pressure builds over the metropolitan today. Low pressure begins to develop S
of the region Friday.

VFR through the taf period...except for dissipating fog this morning.

Mainly northwest winds at or below 10kt. Some backing to the west-northwest this
afternoon...especially S coasts. Direction veers to the north overnight.

New York 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: some variability in wind direction can be
expected through 14z.

Klga fcster comments: some variability in wind direction can be
expected through 14z.

Kewr fcster comments: some variability in wind direction can be
expected through 14z.

The afternoon kewr haze potential forecast is green...which implies
slant range visibility 7sm or greater outside of cloud.

Kteb fcster comments: some variability in wind direction can be
expected through 14z.

Khpn fcster comments: no unscheduled amendments expected.

Kisp fcster comments: no unscheduled amendments expected.

Outlook for 06z Friday through Monday...
Thursday night...VFR.
Friday...ceilings lower through the day with MVFR possible late.
Friday night-Sat night...MVFR or lower. Precipitation mainly rain...but snow may
mix in across the interior at night. NE-north winds 15-20g25-35kt.
Sunday...VFR. Northwest winds 15-20g25-30kt.
Monday...VFR. West winds 5-10 knots.


made minor changes this update to reflect the latest trends in
observations and guidance. The forecast appears on track.

A relaxed pressure gradient over the waters around Long Island
will result in winds 10 knots or less through Friday. The only
exception to this is possibly over the far eastern coastal ocean
waters on Friday afternoon...where NE flow could strengthen to up
to 15 knots. As a result...sub-small craft conditions are expected on
all marine zones through Friday.

Small Craft Advisory conditions are likely to develop on all waters from Friday
night into Sat morning as NE flow strengthens...then expect
northerly gales on the ocean by Sat afternoon...and north-northwest gales on
all waters - especially the ocean and the eastern sound/bays Sat night
into Sunday. Conditions should then gradually subside from Sunday
night on...with sub-Small Craft Advisory conditions on the sound/Harbor/bays by Monday
morning...and on the ocean by Monday night.


dry through Friday morning. There is a slight chance of at most a
few hundredths of an inch of rainfall Friday afternoon mainly
across Long Island.

Rainfall from Friday night through Saturday night is expected to
remain under a half inch with the higher amounts generally across
the coastal areas. No significant hydrologic impact is expected.


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


near term...maloit
short term...maloit
long term...jc

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