Scientific Forecaster Discussion
Area forecast discussion
National Weather Service New York New York
334 PM EDT Friday may 22 2015
a cold front moves east this evening. High pressure builds across
the area over the weekend. Bermuda high pressure remains through
next week. A warm front moves across the western portion of the
area Monday morning.
Near term /until 6 am Saturday morning/...
a cold front will move across the region this evening...with gusty
winds and much colder air in its wake. The gusty winds will continue
through about midnight...then start to diminish. Gusts could range
as much as 20-25 miles per hour this evening. Also...any left over showers with
the front should quickly move east...with dry weather after
850 temperatures fall to between 0 and -2c tonight. Followed a blend
of mav/met guidance for overnight lows tonight. Lows at the surface
will drop into the 30s and 40s. Temperatures in a few spots may tie
or break records tonight. See the climate section below 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 airmass
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 airmass
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 airmass showers and thunderstorms will be
diurnally driven with minimal cape and marginal instability.
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 /20z Friday through Wednesday/...
low pressure will track off the NC coast this evening and pass east of Cape Cod
on Friday. A cold front will track through the region Friday afternoon.
Best chance for -ra along a kjfk-kisp line in association with the
passing low. Mainly VFR...although some pockets of MVFR possible due
to ceilings around 3000 feet in the -ra. The precipitation ends from west to east
overnight...with scattered-broken 6000 feet clouds Friday.
Fairly light S/south-southwest flow generally blw 10 knots through 00z. Variability in
the light flow through 5-9z...then northwest flow develops as the low passes east
of the area and strengthens.
In the extended tafs...a shot of stronger winds behind the cold
front Friday afternoon.
..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: low probability for ceilings to drop blw 3000 feet
Klga fcster comments: terminal will be close to the northern edge of the -
rain shield. Amendments possible if this area shifts northward.
Kewr fcster comments: terminal will be close to the northwestern edge of the
-ra shield. Amendments possible if this area shifts northward.
Kteb fcster comments: no unscheduled amendments expected.
Khpn fcster comments: no unscheduled amendments expected.
Kisp fcster comments: no unscheduled amendments expected.
Outlook for 18z Friday through Tuesday...
Friday...winds shift to the northwest at 20-30kt behind a cold front. Speeds
diminish after 00z.
Sat...VFR with light winds becoming west 10-20kt in the afternoon.
Sun...VFR with west-southwest winds 15-25kt.
Monday...VFR to start...then MVFR possible in vicinity of a warm front. Rain showers
possible. Flow becoming southerly.
Tuesday...periods of MVFR or lower possible with stratus and fog. SW
the pressure gradient tightens this evening and first part of
tonight with wind gusts 25 to 30 knots ahead of a cold front...with the
strongest wind expected near the shore. A Small Craft Advisory is in
effect for all waters through tonight. Winds are expected to
diminish on Saturday...with sub Small Craft Advisory conditions.
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.
The wind and gusts are expected to remain below small craft Sunday
through Thursday with warmer air moving over the cooler waters. Some
near shore gusts in the afternoons may approach small craft 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.
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 20-25 miles per hour. Fire weather concerns will
be addressed with an 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
Marine...Small Craft Advisory until 6 am EDT Saturday for anz330-335-
near term...British Columbia
short term...British Columbia