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Area forecast discussion 
National Weather Service New York New York
652 PM EST Thursday Dec 25 2014

Synopsis...
high pressure builds over the southeastern U.S. Through Saturday. A
cold front crosses the tri-state on Sunday. This front stalls out
well to the south of Long Island...as cold Canadian high pressure
builds in from the west throughout next week. Multiple lows pass
along the front for the early part of next week.

&&

Near term /until 6 am Friday morning/...
strato-cumulus mixing out with loss of surface heating early this
evening with skies becoming clear. Forecast overall is on track
with only minor adjustments made to better match observed trends
with dewpoint and temperatures.

Winds drop off quickly as high pressure builds in from the west
with a decrease in the pressure gradient. Lows are blended NAM
and GFS MOS which had nearly no spread.

&&

Short term /6 am Friday morning through Saturday/...
ridging aloft with above normal temperatures for the period.

Have forecast above NAM/GFS MOS based on nearly full sun and 552 dm
thickness for Saturday. Also...ensemble MOS from 00z..ekd MOS and
GFS parallel all suggesting 50-55. Looks like a great day to be
outside with light winds.

&&

Long term /Saturday night through Thursday/...
overall...in the middle to upper levels...the ridge flattens going
into early next week. This leaves a zonal flow through midweek and
then a trend towards more of a trough across the northeast towards
the end of the week.

At the surface...a weak parent low moves through southeast Canada
and into the Canadian Maritimes Sunday...dragging a cold front
across. The front then stalls well south of Long Island going into
early next week with multiple areas of low pressure riding along
the front. One big feature to note next week is the very strong
high pressure moving into the northwest U.S. Likewise...a very
cold source of air will be moving into the northwest U.S. This
airmass gradually moves south and east through the week.

In terms of sensible weather...an increasing chance of
precipitation late Saturday night into Sunday associated with the
cold frontal passage. The amounts are light...with less than a
quarter of an inch likely. Much of it is forecast to fall during
the day Sunday into Sunday evening...so this allows most precipitation to
be rain showers especially near the coast. Interior will probably
have more chance of seeing some snow showers. The next precipitation is
only slight chance for Monday into possibly Monday evening. Colder
air in place here but amounts very light...a few hundredths of an
inch or less. The precipitation will be a mix of rain and snow...but
again with aforementioned light amounts...no accumulation of any
snow is forecast.

Temperatures overall a colder trend. Above normal highs
Sunday...near normal Monday...and below normal thereafter.

&&

Aviation /00z Friday through Tuesday/...
high pressure will continue to build in. Gusty west flow will gradually
diminish and broken VFR ceilings will also scatter after sunset.

VFR on Friday...with westerly flow gradually backing SW late in the
day. Few-scattered 2 kft cumulus.

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: occasional gusts to 20 knots possible between
13z and 16z Friday. Timing of winds backing may be off by 1 to 2
hours. Few- scattered 2 kft cumulus in the afternoon.

Klga fcster comments: occasional gusts to 20 knots possible between
13z and 16z Friday. Timing of winds backing may be off by 1 to 2
hours. Few-scattered 2 kft cumulus in the afternoon.

Kewr fcster comments: occasional gusts to 20 knots possible between
13z and 16z Friday. Timing of winds backing may be off by 1 to 2
hours. Few-scattered 2 kft cumulus in the afternoon.

Kteb fcster comments: timing of winds backing may be off by 1 to 2
hours. Few-scattered 2 kft cumulus in the afternoon.

Khpn fcster comments: timing of winds backing may be off by 1 to 2
hours. Few-scattered 2 kft cumulus in the afternoon.

Kisp fcster comments: timing of winds backing may be off by 1 to 2
hours.

Outlook for 00z Sat through Tuesday...
Friday night-Sat...VFR.
Sunday...MVFR with chance of light rain.
Monday...VFR.
Tuesday...low confidence VFR.

&&

Marine...
winds and waves generally on track with Small Craft Advisory times kept the same as
previous forecast.

Winds lower through the evening to Small Craft Advisory level by midnight. Waves
on the ocean that are currently as high as 7 feet will lower as
well. Waves on the eastern ocean waters could possibly hold on to
5ft Small Craft Advisory criteria a few hours after the Small Craft Advisory ends at 08z.

Sub-Small Craft Advisory conditions are anticipated on Friday into next week. The
only exception would be Sunday when 5 feet seas are forecast for the
ocean southeast of Montauk Point. There is uncertainty associated
with this and is dependent on how the cold front and parent low
trend with the response of the pressure gradient.

&&

Hydrology...
dry through Saturday night with no significant precipitation expected
from Sunday-Wednesday at this time.

&&

Okx watches/warnings/advisories...
CT...none.
New York...none.
New Jersey...none.
Marine...Small Craft Advisory until midnight EST tonight for anz330-335-
338-340-345.
Small Craft Advisory until 3 am EST Friday for anz350-353-355.

&&

$$
Synopsis...tongue
near term...jm/tongue
short term...tongue
long term...jm
aviation...Nevada
marine...jm/tongue
hydrology...jm/tongue

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