Scientific Forecaster Discussion
Area forecast discussion
National Weather Service New York New York
736 PM EDT Wednesday Jul 1 2015
a cold front will moves through this evening...and then settles
just south of the area overnight into Thursday. High pressure will
then build in from Thursday night into Friday...and remain through
Tuesday as waves of low pressure pass to the south Friday night
into Saturday...and Sunday night into Tuesday night. A cold front
will approach on Wednesday.
Near term /until 6 am Thursday morning/...
cold front is moving into western portions of Orange County as of
22z. Not much shower and thunderstorm activity along it...with the
most significant activity over northern New England. The atmosphere
as a whole has been drying out behind departing shortwave from
this morning...and convergence along the front is weak. Feel the
threat for any strong to severe thunderstorms has diminished with
lowering cape values and dew points fall into the upper 50s and
lower 60s. The highest cape is located across southeast CT...where about
500 j/kg exists. Even this has been decreasing over the last few
hours as the maritime influence takes over from onshore flow. An
isolated shower or storm cannot be ruled out as the front moves through
The front moves offshore after midnight. Skies will become mostly
clear. Lows will range from near 70 in Midtown NYC...to the 60s
most elsewhere...to some upper 50s in the valleys of Orange County
and in the Long Island Pine barrens.
Short term /6 am Thursday morning through Thursday night/...
the cold front should stall not too far off to the south on Thursday.
Expect dry conds for the most part...though with area in right
rear quadrant of upper jet expect plenty of high/middle level clouds
mainly across NYC metropolitan and Long Island. Enough late day
instability may also build for a late day shower/thunderstorm in/near
NE New Jersey. High temperatures should be similar to those of today...lower and
Flow will be weak enough to allow sea breeze development...though
not nearly as strong as the past couple of days.
Once the upper jet passes to the east late Thursday night...high
pressure should start to build in from the Great Lakes...with north-NE
flow and mostly clear skies. As a result lows will be a cooler
Lower/Middle 60s in most places...and 55-60 across the interior.
Long term /Friday through Wednesday/...
a broad upper trough remains across the northeast Friday into
Saturday with shortwaves rotating through the trough. The upper
trough weakens Saturday night and moves offshore Sunday as ridging
builds over the area. Meanwhile at the surface one wave of low
pressure passes to the south Friday night into Saturday. The
northern fringes of the precipitation shield may reach Long Island.
At this time will keep just slight chance probability of precipitation across eastern Long
Island as the wave passes. Another wave passes Sunday night into
Tuesday. However with ridging across the region this wave will be
farther to the south and is not expected to affect the area. Tuesday
the upper ridge moves offshore as a northern stream trough digs into
the northern plains and upper Midwest. A weak shortwave could bring
some showers and thunderstorms by Tuesday afternoon into Tuesday
night. With the uncertainty will be probability of precipitation at slight chance at this
time. Wednesday a stronger shortwave accompanied by a surface cold
front will bring a better chance for precipitation.
Aviation /00z Thursday through Monday/...
a cold front moves across the area tonight. High pressure builds into
the region on Thursday.
VFR conds. Isolated showers/thunderstorms are expected into the
early evening...mainly northwest of NYC terminals...but coverage is
forecast to be too low to include in the taf.
SW winds will veer to the west-northwest and diminish to 5-10 knots early this
evening before becoming light/vrb by midnight tonight.
Light winds in the morning will give way to afternoon sea breezes.
... 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: no unscheduled amds expected.
Klga fcster comments: no unscheduled amds expected.
Kewr fcster comments: no unscheduled amds expected.
Kteb fcster comments: no unscheduled amds expected.
Khpn fcster comments: no unscheduled amds expected.
Kisp fcster comments: no unscheduled amds expected.
Outlook for 00z Friday through Monday...
Thursday night...VFR with diminishing winds.
Friday...VFR with winds veering from the NE to the east-southeast. Sea breezes
Friday night-Sat...low pressure will track S of the region. If the low is
close enough...MVFR or lower possible with -ra. Winds generally NE
seas at 44017 have been slow to rise to 5 feet...but recent observation show
seas building with a 2-3 feet swell and S-SW flow just over 15 knots.
Still feel seas will build up to 5 feet east of Moriches Inlet. Small Craft Advisory
for hazardous seas continues there.
A weak pressure gradient will be across the forecast waters Thursday
through Monday. Generally high pressure will be across the
waters...with one low passing to the south Friday night into
Sat...and another low passing south slowly from Sunday night
no significant precipitation is expected during the forecast
with full moon...tidal departures of only 3/4 to 1 1/2 feet are
needed for minor coastal flooding benchmarks to be reached at the
peak of the nighttime high tides the next few days.
Minor benchmarks could briefly be touched along the South Shore
bays of Nassau County through late this week.
Marine...Small Craft Advisory for hazardous seas until 6 am EDT
Thursday for anz350.