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Area forecast discussion 
National Weather Service New York New York
632 PM EST Friday Mar 6 2015

Synopsis...
high pressure extending from the Ohio Valley into the Southern
Plains will build over the southeast states through Saturday as a
clipper system tracks from south central Canada into the Great
Lakes region. A cold front passes through the area Saturday night
followed by high pressure Sunday through Monday night. Weak low
pressure passes south and east Tuesday into Wednesday morning
followed by high pressure for the remainder of the week.

&&

Near term /until 6 am Saturday morning/...
increased clouds with the forecast based on satellite. Otherwise no major
changes made.

High pressure centered over the deep south with ridge axis
extending NE across the region this evening...sliding south
after midnight. Light winds and clear skies above the snowpack
could lead to some good radiational cooling before high clouds
cross late as a weak shortwave aloft slides through. Temperature forecast
is tricky with a large difference between mav and met MOS
guidance. Will lean towards the colder side of guidance in most
places for above reasons...but with west-southwest flow and weak warm
advection late its possible that temperatures hold steady late at night.
Lows generally 15-20f in NYC...and as low as 5f in The Pine
Barrens and the normally colder spots north/west of NYC.

&&

Short term /6 am Saturday morning through Saturday night/...
clouds will increase and thicken Saturday into Saturday evening
as another potent shortwave tracks just north of the region. GFS
is a little more aggressive than other models in bringing flurries
or light snow showers all the way to the coast by evening. Still
feel best chances reside north of NYC and will keep coastal areas dry
for now. High temperatures climb into the lower to middle 30s most
places...warmer but still well below normal.

Shortwave slides east of the region by midnight tomorrow night...but
with overcast conditions and west-west-southwest flow temperatures will only drop off a
few degrees outside of NYC. In the city...temperatures may drop initially
then hold steady or rise a few degrees overnight.

&&

Long term /Sunday through Friday/...
a broad upper level trough will persist across southeast Canada late
weekend into early next week with rising heights Tuesday into
Wednesday. High pressure will build into the region Sunday and
persist through Monday night. The flow across the country is of
Pacific origin...so temperatures will be able to rise into the upper
30s and lower 40s Sunday and Monday. These readings are a little
below normal...but much closer to normal than what we have seen
recently.

The southern branch of the upper level jet sends a weak wave towards
our area late Tuesday into early Wednesday as heights rise along the
East Coast. Confluent flow across the northeast between the
northern and southern branch of the jet is likely to keep this wave
far enough south. The GFS and CMC keep the system to the south.
However...the latest 12z European model (ecmwf) and a few GFS ensemble members depict
weaker confluence and thus bring the wave further north with a quick
shot of precipitation across at least the southern half the County Warning Area.
Have increased probability of precipitation to slight chance across the southern half of the
County Warning Area. Subsequent model trends will have to be watched and probability of precipitation may
need to be raised further in future forecast packages if a trend
towards weaker confluence and a further north track continues. With
warmer temperatures...any precipitation from the system will be
rain. The system quickly moves offshore during the day on Wednesday.
Temperatures on Tuesday will be in the lower and middle 40s and for
Wednesday in the middle and upper 40s. A few 50 degree readings
possible in the NYC metropolitan and NE New Jersey on Wednesday.

Canadian high pressure builds into the region for the end of the
week with high temperatures falling back below normal in the
upper 30s and lower 40s.

&&

Aviation /00z Saturday through Wednesday/...
high pressure builds over the region tonight through Saturday. An
upper trough moves across the region Saturday night.

VFR through the taf period...with a broken-overcast deck at 100-150 kft
after 20z Saturday.

Wind forecast...for knyc terminals...S/SW winds 5-10 knots will
become west/northwest at 8-12 knots after midnight tonight...and then will
become west/SW late Saturday afternoon and Saturday night.

For terminals away from knyc...generally light/vrb winds
tonight...becoming SW 5-10 knots in the afternoon and early evening.

... 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: high confidence wind/flight category
forecast through the taf period.

Klga fcster comments: high confidence wind/flight category
forecast through the taf period.

Kewr fcster comments: high confidence wind/flight category
forecast through the taf period.

Kteb fcster comments: high confidence wind/flight category
forecast through the taf period.

Khpn fcster comments: high confidence wind/flight category
forecast through the taf period.

Kisp fcster comments: high confidence wind/flight category
forecast through the taf period.

Outlook for 00z Sunday through Wednesday...
Sat night...slight chance MVFR conds in -shsn.
Sunday through Wednesday...mainly VFR.

&&

Marine...
generally light flow this evening becomes west-west-southwest around 15kt
overnight into Saturday. Winds on the ocean become 15-20kt late
Saturday. Some gusts possible especially on the ocean waters to
near 25kt late Saturday into Saturday night with seas building to
4-5ft. This may eventually require an Small Craft Advisory but with marginal
conditions and short duration will hold off for now.

With high pressure building over the waters Sunday into Monday
night...seas and winds will be below Small Craft Advisory levels. A weak wave of low
pressure passes south of the waters Wednesday...but conditions
should remain below Small Craft Advisory.

&&

Hydrology...
no significant precipitation is expected through early next week.

However...temperatures forecast to warm into the 40s may result in the start
of ice break up on area rivers and streams.

&&

Climate...
record low information from this morning follows.

Station low temperature old record
ewr 12 12/2007 (tied)
bdr 9 11/2007 (broken)
NYC 12 6/1872 (no record)
LGA 15 14/2007 (no record)
JFK 13 13/2007 (tied)
isp 12 12/2007 (tied)

&&

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

&&

$$
Synopsis...gs/ds
near term...jmc/gs
short term...gs
long term...ds
aviation...mps
marine...gs/ds
hydrology...gs
climate...gs/tfm

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