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Area forecast discussion 
National Weather Service New York New York
827 PM EDT Friday may 22 2015

a cold front will move across tonight. High pressure will then
build across over the weekend. A warm front will pass to the north
Monday morning...followed by Bermuda high pressure remaining in
place through next week.


Near term /until 6 am Saturday morning/...
as of 23z...a pre-frontal trough had passed just to the south and
east. Isolated showers associated with the pre-frontal trough and a
weak shortwave trough aloft should clip the lower boroughs of NYC
and the New Jersey suburbs to the west.

Surface cold front just northwest of the lower Hudson Valley and southern CT
should move through this evening...with gusty winds and much
cooler air in its wake. Followed a blend of 12z GFS/NAM MOS
guidance for lows tonight... with temperatures dropping into the 30s and
40s. Temperatures in a few spots may tie or break record lows tonight.
See the climate section for details.

There is a low chance we see some frost development across Orange
County. Thinking that winds could be just enough to prevent any
development. Confidence is low and will need to monitor.


Short term /6 am Saturday morning through Saturday night/...
Saturday will be dry and breezy as high pressure builds into the
area. Highs on Saturday will be in the middle and upper 60s. High
pressure shifts offshore Saturday night with dry weather continuing.
Winds out of the southwest will keep a relatively more mild air
mass with low temperatures falling into the upper 40s and 50s.
60s are expected in and around the New York City metropolitan. Followed a
mav/met blend for temperatures.


Long term /Sunday through Friday/...
upper ridge will be building into the eastern sea board Sunday
through Tuesday as surface Bermuda high pressure remains offshore. A
low and shortwave moving into the northern plains Sunday night into
Monday will result in a weak warm front developing across the Great
Lakes and into eastern Pennsylvania Sunday night into Monday...with
the front moving north of the region Monday morning. Forcing will be
weak with the front...and have low chance and slight chance probability of precipitation
across the interior. Little cape and instability will accompany the
front and will have showers for that time frame.

The ridge and surface high remain in place Tuesday night through
Thursday with a southwesterly flow keeping a warm and humid air
mass in place. For Tuesday and Wednesday afternoons and into the
evenings each day there will be a low chance for showers and
isolated thunderstorms around the periphery of the ridge as weak
surface troughs develop. The air mass showers and thunderstorms
will be diurnally driven with minimal cape and marginal

A shortwave will be moving into the ridge from Thursday afternoon
into Friday with the wave moving north of the area Friday afternoon.
So the better chance of precipitation...especially inland as the
high remains off shore...will be Thursday afternoon into Friday.


Aviation /00z Saturday through Wednesday/...
a cold front will continue to track through the region this evening. Hi
pressure builds in from the west on Sat.

VFR through the taf period.

Scattered-isolated rain showers in vicinity of the city terminals through 01z-02z.

Pre-frontal trough has moved through with a temporary shift of
winds to the northwest. They have since backed to the west/west-southwest ahead of the
cold front looks to be extending from just S of kpvd to kdxr to
kmpo. Flow becomes northwest after the frontal passage. Speeds and gust frequency
diminish overnight. Winds then back to the west around 10kt on Sat.
Gusts in the teens also possible during the afternoon. Stronger SW
flow kjfk due to possible sea breeze influence.

..NY 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: cold frontal passage around 02-03z with wind shift
right of 310 magnetic. Gusts in the middle 20s expected through
the remainder of evening push.

Klga fcster comments: cold frontal passage around 02-03z with wind shift
right of 310 magnetic. Gusts in the middle 20s expected through
the remainder of evening push.

Kewr fcster comments: cold frontal passage around 02-03z with wind shift
right of 310 magnetic. Gusts in the middle 20s expected through the
remainder of evening push.

Kteb fcster comments: cold frontal passage around 02-03z. Gusts up to 20kt
expected through 04z or so...could end earlier.

Khpn fcster comments: cold frontal passage around 02-03z. Gusts up to 20kt
could end earlier than forecast.

Kisp fcster comments: cold frontal passage around 02-04z. Gusts up to 20kt
possible Post frontal...03z to 06z...although could be more occasional.

Outlook for 00z Sunday through Wednesday...
Sat night...VFR. Winds diminishing.
Sun...VFR. SW winds 10-20kt.
Monday...VFR. SW winds 10-20kt.
Tuesday...morning MVFR or lower possible in fog/stratus. SW winds.
Wednesday...pockets of MVFR or lower possible in fog/stratus. SW


winds were gusting to 25 knots in New York Harbor and the adjacent near
shore ocean waters...but were below Small Craft Advisory criteria elsewhere.
Expect wind gusts just over 25 knots on all waters late tonight after
cold frontal Small Craft Advisory remains in effect. Winds should diminish
on Sat.

Bermuda high pressure will remain in place Sunday through at least
Thursday with a south to southwest flow across the forecast waters
through the period. With a shortwave moving into the area Thursday
there will be a chance for showers and thunderstorms.

Winds and gusts should remain below Small Craft Advisory criteria Sunday through
Thursday with warmer air moving over the cooler waters. Some near
shore gusts each afternoon may approach Small Craft Advisory levels.

With a persistent southwesterly flow seas on the ocean waters are
expected to eventually build to small craft levels. At this time
this is expected to occur Monday night with seas then remaining
at small craft levels into Thursday.


Fire weather...
Saturday will be another day of fire weather concern especially for
NYC metropolitan...southern CT and Long Island...with min relative humidity again in the
20s and northwest-west winds gusting to 20 miles per hour. These concerns will be
addressed with a Special Weather Statement.


no significant widespread rain expected through the forecast


we will come close to breaking low temperatures tonight at a few of
our climate sites. Below are the records and forecast lows for our 6
climate sites.

Central Park....48...........43/1963


Okx watches/warnings/advisories...
New York...none.
New Jersey...none.
Marine...Small Craft Advisory until 6 am EDT Saturday for anz330-335-


near term...BC/Goodman
short term...British Columbia
long term...met
fire weather...

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