Scientific Forecaster Discussion
Area forecast discussion
National Weather Service New York New York
156 am EDT Monday Sep 22 2014
a cold front crosses the tri-state overnight...meanwhile a coastal
low tracks to the east...then northeast of Long Island. High
pressure then builds in from the west through Tuesday. The high
then dominates the weather through next Sunday.
Near term /until 6 am this morning/...
cold front approaching from the west seems to be through Orange
County New York as of 04z and will continue east. Scattered rain showers
are accompanying the front. Even with dry air in place...showers are
not dissipating as quickly as previously forecast. Have added probability of precipitation
for Long Island and central/eastern CT through the next few hours.
Patchy fog still in place over our eastern CT counties and
clearing up over Long Island. Expect fog to lift with the passage
of the cold front. Fog could be locally dense at times.
Otherwise...made minor adjustments to T/dew point based on trends.
Short term /6 am this morning through 6 PM Tuesday/...
region remains under the base of 700-500 hpa trough Monday and
Monday night. Will have a few shortwaves round the base of the
trough - but given forecast drying in the low levels would only
expect at most some clouds as they pass. So going with a mostly
sunny to partly cloudy sky Monday and a mostly clear to clear sky
Monday night as a result.
For highs Monday used a blend of mixing down from 875 hpa...except
850 hpa over the northwest 1/4 of the County Warning Area per BUFKIT soundings...with NAM
2-meter temperatures and a blend of mav/met guidance. Expect
readings to be near to slightly below normal.
A blend of mav/met guidance was used for lows Monday night - with
readings forecast to be 5-10 degrees below normal. Lows in the upper
30s are possible in portions of Orange County.
There is a moderate risk of rip currents at Atlantic beaches
Long term /Tuesday night through Sunday/...
a strong upper ridge will be building into the East Coast Tuesday
and Tuesday night...then remain nearly stationary through Sunday.
At the surface high pressure builds east from the Ohio Valley while
another surface high builds in from central Canada. The combined
high pressure center will build east from the Great Lakes and
through northern New England Tuesday into Wednesday. The high then
builds over the region Thursday and remains nearly stationary into
Sunday. Initially the air mass will be cool Tuesday into
Thursday...with slightly below seasonal normal temperatures. A
warming trend sets up for Thursday night through Sunday as the air
mass modifies. Next weekend temperatures will have rebounded to
above seasonal normals.
Aviation /06z Monday through Friday/...
cold front pushes east early this morning...with high pressure
gradually building into the region from the west tonight.
West-northwest winds in wake of front early this morning...increase and
become gusty after daybreak with isolated gusts to 30kt. Winds
generally will waver between 290 and 320 mag during the day. For
city terminals...winds should average just right of 310 mag this
morning...then could back a to left of 310 mag at kjfk/kewr this
afternoon ahead of trough approach. Winds and gust subside this
evening...veering generally right of 310 mag.
IFR ceilings across kgon...becomes VFR behind the front by 08z. A few
-shra with front. Otherwise...VFR today with scattered-broken 4-5kft cumulus
Outlook for 06z Tuesday through Thursday...
late Monday night...VFR. Northwest winds diminishing.
Tuesday...VFR with light winds.
Wednesday...MVFR ceilings around 3000ft possible. East-northeast winds 5-15kt.
Thursday...VFR with light NE flow.
seas build to up to 5 feet on the western coastal ocean waters and
up to 8 feet on the eastern coastal ocean waters overnight. With wind
gusts up to 25 knots on the coastal ocean waters on Monday - will
continue the Small Craft Advisory. Small Craft Advisory wind gusts should linger
over the eastern two coastal water zones into Monday evening and
Small Craft Advisory level seas through the night in those two zones...so have
extended the Small Craft Advisory for anz-350 and 353 through 10z Tuesday as a
On the remainder of the coastal ocean waters sub-Small Craft Advisory conditions are
currently expected through Monday night. Wind gusts to 20 knots are
forecast on Monday - however occasional gusts to 25kt cannot be
There is a chance of lingering 5 foot seas across the extreme outer
ocean waters east of Moriches Inlet very early Tuesday morning as
seas will be subsiding as high pressure builds in.
With high pressure across the waters Tuesday into Saturday wind and
seas are expected to remain below Small Craft Advisory levels.
little if any additional rainfall is expected through tonight with
the passing of a coastal low to the east and the passage of a
Dry conditions expected from Monday through next Sunday.
Marine...Small Craft Advisory until 6 PM EDT this evening for anz355.
Small Craft Advisory until 6 am EDT Tuesday for anz350-353.