Scientific Forecaster Discussion
Area forecast discussion
National Weather Service New York New York
944 am EST Friday Dec 26 2014
high pressure will build in today...then slide east on Saturday.
A cold front will move across Sunday...then cold Canadian high
pressure builds in from the west throughout next week. Multiple
lows will pass to the south early next week.
Near term /until 6 PM this evening/...
a sunny and somewhat mild early winter day expected today.
Broad ridging building up the East Coast...a light west flow and
800 mb temperatures around 4c should yield surface high temperatures in the middle and
upper 40s...about 5-10 degree above average.
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 air mass gradually moves south and east through
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
Temperatures overall a colder trend. Above normal highs
Sunday...near normal Monday...and below normal thereafter.
Aviation /15z Friday through Tuesday/...
VFR as high pressure builds in from the south today. West-northwest surface winds
lighten this afternoon as they backs to the west-southwest.
Sky clear with a few-scattered cumulus at 3000' over the interior hills this
... 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: gradual backing of wind direction to SW this
afternoon. Could even go left of 220 mag...though high confidence in
less than 10 knots.
Klga fcster comments: gradual backing of wind direction to west-southwest
Kewr fcster comments: gradual backing of wind direction to west-southwest this
afternoon. Direction could be even be closer to 230. High confidence
in less than 10 knots and no gusts.
The afternoon kewr haze potential forecast is green...which implies
slant range visibility 7sm or greater outside of cloud.
Kteb fcster comments: gradual backing of wind direction to SW this
Khpn fcster comments: gradual backing of wind direction to west-southwest this
Kisp fcster comments: gradual backing of wind direction to SW this
Outlook for 12z Sat through Tuesday...
Sunday...chance -shra...MVFR possible.
Monday and Tuesday...VFR likely.
sub-Small Craft Advisory conditions anticipated into next week. The only exception
could be Sunday when 5 feet seas may be possible 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.
no significant precipitation expected at this time.