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Area forecast discussion 
National Weather Service New York New York
551 am EST Friday Dec 26 2014

Synopsis...
high pressure builds to the East Coast today and slides offshore
on Saturday. A cold front crosses the tri-state on Sunday. This
front stalls out well 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 PM this evening/...
forecast is on track. Only minor adjustments needed to hourly T/dew point
and winds based on latest observation and trends. Otherwise...a sunny and
somewhat mild early winter day expected across the area today.
Broad ridging building up the East Coast...a light westerly flow and
850 mb temperatures around 4c should yield surface high temperatures in the middle to
upper 40s across the region. This is between 5 and 10 degrees
above normal levels.

&&

Short term /6 PM this evening through Sunday night/...
deep upper trough/cutoff low pressure over The Four Corners region
early this morning will weaken this weekend with its residual
energy lifting through the Central Plains tonight and Great Lakes
on Sat before continuing through northern New England and Canadian
Maritimes on Sunday. This systems attending cold front will track
across the area Sun afternoon/evening with a wave of low pressure developing
along the boundary and passing S of Long Island Sun night/Mon.

The NAM continues to be fairly dry with the frontal passage and keeps all
precipitation associated with the wave to the S. The 00z ec is wetter than
the 12z run and similar to the GFS. One main difference between
the two solutions however is the timing of the wave passing to the S.
GFS is Sun night and ec is Monday. This will need to be rectified
over the next few days...but due to the overall wetter
trend...have increased probability of precipitation slightly Sun night into Monday.

A deep SW flow developing on Sat ahead of the cold front will
transport warmer air into the area. Highs are expected to reach
lower to middle 50s Sat and upper 40s to around 50 sun. Lows through
the weekend will also be above normal levels.

&&

Long term /Monday 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...the aforementioned cold front 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...a slight chance of precipitation across
southern zones 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 /12z Friday through Tuesday/...
high pressure will build into the region today.

VFR. Few-scattered 2 kft cumulus likely in the afternoon.

West flow generally under 10 knots till daybreak. Some occasional gusts to
20 knots possible across city terminals this morning. Westerly flow
gradually backs SW late in the day.

Light west-southwest flow tonight.

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: an occasional gust to 20 knots possible this
morning. Winds expected to remain left of 300 true (310 mag) today.

Klga fcster comments: an occasional gust to 20 knots possible this
morning. Winds expected to remain left of 300 true (310 mag) today.

Kewr fcster comments: an occasional gust to 20 knots possible this
morning. Winds expected to remain left of 300 true (310 mag) today.

The afternoon kewr haze potential forecast is green...which implies
slant range visibility 7sm or greater outside of cloud.

Kteb fcster comments: no unscheduled amendments expected.

Khpn fcster comments: no unscheduled amendments expected.

Kisp fcster comments: no unscheduled amendments expected.

Outlook for 06z Sat through Tuesday...
late Friday night-Sat...VFR.
Sunday...MVFR possible with chance of light rain.
Monday...VFR.
Tuesday...low confidence VFR.

&&

Marine...
Small Craft Advisory was dropped this morning. Winds and seas continue
to fall. At this point...any wind gusts to 25 knots would be
occasional. Seas are just below 5 feet and will continue to fall.

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...none.

&&

$$

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