Scientific Forecaster Discussion
Area forecast discussion
National Weather Service New York New York
930 am EST Sat Feb 6 2016
high pressure builds to the south today and tonight. Deep low
pressure will track over the Atlantic late Sunday into Monday. An
active winter pattern will then set up over the area through the
middle of next week.
Near term /until 6 PM this evening/...
tranquil conditions today as high pressure settles in just to our
A filtered sunshine through high clouds and weak warm air advection on SW winds
will help temperatures rise close to seasonal norms.
Short term /6 PM this evening through 6 PM Sunday/...
surface high remains nearby tonight but should yield to developing
and deepening low pressure off the southeast coast Sunday. Trough
moving across the southeast states moves off the southeast coast Sunday
as next northern stream trough digs across the upper Midwest with
surface low moving toward the Great Lakes region. Dry weather
continues with scattered clouds at most during this time.
Temperatures tonight should fall close to seasonal norms. Some
radiational cooling could take place with snow pack and mainly
clear skies...but light SW wind flow may prevent ideal
radiational cooling from occurring.
On Sunday...temperatures rise into the lower to middle 40s...slightly
Long term /Sunday night through Friday/...
challenging forecast with many features in play.
Once again...southern stream trough moves off the southeast
coast...driving deep surface low offshore...passing somewhere south
and east of the benchmark. Then large trough approaches from the
west...and yet another low develops over the western
Atlantic...this one much closer to the area.
Concern for eventual placement of first low offshore...followed
by next low and track Tuesday. Large model/ensemble spreads on
Based on latest model guidance...NAM and sref much wetter Monday
as low tracks further northward compared to GFS/ECMWF...and quantitative precipitation forecast
shield extends much further northwestward...over the forecast
Have decided to not stray too far from previous forecast...which
is supported by wpc and latest models blend suite. Would expect
precipitation to approach from the south Monday on the north side of the
Even if that does not occur...lift ahead of the approaching
trough should result in the development of light snow before next
low develops off the middle Atlantic coast.
As the initial southern stream trough pivots off the southeast
coast and departs to the east...and next trough approaches and
slowly moves across the eastern United States...we could be
looking at a prolonged period of snow from Monday through
Wednesday. Occasional light snow is quite possible. Cannot though
rule out possible heavier quantitative precipitation forecast if ingredients come together for
Have higher confidence that unsettled weather with snow at times
may very well occur Monday through Wednesday. However...have much
lower confidence in exact details and where any heavier snow
bands set up. Stay tuned.
Arctic air still looks poised for the weekend. The European model (ecmwf) Ushers
it in with a clipper Friday which would bring more snow chances.
In summary...there are chances for precipitation in every period of the
Aviation /15z Saturday through Wednesday/...
high pressure builds to the south today and gradually weakens
VFR through the taf period. Moderate to high confidence in wind
Outlook for 12z Sunday through Wednesday...
Sunday night and Monday...chance sub-VFR and snow...especially east of
city. Chance NE gusts around 25kt.
Tuesday...sub-VFR with snow likely...possibly mixed ptype during
the afternoon at the coast...tapering off late in the day.
Wednesday...chance sub-VFR with -shsn. Northwest gust around 25kt.
Sub-advsy conds will prevail on all waters through Sunday with
high pressure to our south. Winds gusts around 20 knots likely late
today into this evening...with seas building to around 4 feet on
the eastern ocean waters.
An area of low pressure develops off the southeast coast Sunday...intensifying
as it tracks NE. The pressure gradient will tighten Sun night with
gale force winds possible after midnight. The best chance for gales
currently exists on the ocean waters and eastern Li sound/bays so
have issued a gale watch for these zones. The strong winds are
forecast to continue through much of the day Monday. Otherwise...Small Craft Advisory
likely during this time.
Small Craft Advisory is then likely on most of the waters into Tuesday as a weaker low
pressure system is forecast to pass closer to the local area. Winds
then decrease temporarily Tuesday night...although seas on the ocean
will remain above 5 feet...before increasing again on Wednesday from a
tightening pressure gradient.
widespread precipitation is possible late Sunday night through
Monday...and again during the middle of next week. Most if not all of
the precipitation that falls likely to be in the form of snow at this time.
Widespread precipitation is possible late Sun night through Monday...and again during
the middle of next week. Most if not all of the precipitation that falls
likely to be in the form of snow at this time.
with the approach of the new moon on Monday and potential for nerly
winds Monday and Tuesday...will have to monitor tides for possible minor
Marine...gale watch from late Sunday night through Monday afternoon for
near term...precipitable water
short term...precipitable water