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fxus61 kokx 190235 
afdokx

Area forecast discussion
National Weather Service New York New York
1035 PM EDT Fri Oct 18 2019

Synopsis...
high pressure builds across the area overnight into Saturday,
then offshore Saturday night. Tropical storm Nestor is then
forecast to track well south of the region Sunday into Sunday
night. Weak high pressure follows for Monday before a frontal
system moves across the area Tuesday into Tuesday night. High
pressure will then close out the week.

&&

Near term /until 6 am Saturday morning/...
cyclonic flow slowly moving northeast as a ridge builds to the
west, through western upstate New York and through eastern
Pennsylvania. Strato cu remains across southern Connecticut and
into portions of eastern Long Island. Forecast on track.

A progressive upper air pattern will feature a departing trough
along the East Coast and a building ridge from the west.
Surface high pressure approaches tonight with diminishing
northerly winds. This combined with clear skies and dry air will
allow for good radiational cooling. A frost advisory remains up
for most of the lower Hudson Valley, interior southern CT, and
portions of interior NE New Jersey. The western half of Orange County New York
will be close to freezing, but there is less confidence for a
freeze warning versus a frost advisory at this time. Frost will
be more patchy across The Pine Barrens region of eastern Long
Island.

Lows will be in the 30s to around 40 outside of the NYC Metro,
which will get down into the lower and mid 40s. These readings
are a few degrees below normal.

&&

Short term /6 am Saturday morning through Sunday night/...
both the upper ridge and surface high build across the area on
Saturday with light winds, clear skies, and highs around 60.
The latter of which is just a shade below normal.

Saturday night will feature another night of light winds. There
will an increase in high clouds late ahead of an upper trough
lifting NE across the Mississippi Valley. The latter of which
will steer tropical storm Nestor off the Carolina coast on
Sunday. Before then though, there could be another night of
frost across the interior and Pine barrens region of eastern
Long Island.

For Sunday, Nestor tracks well south and east of the region
with the forecast area on the northern fringe of the rain
shield. Rain chances are only 20 to 30 percent at this time,
highest across Long Island and the NYC Metro. The cloud shield
is expected to encompass the entire area with temperatures a
shade cooler than on Saturday. Any rain should exit to the south
and east early Sunday evening.

Models are generally in good agreement with the track of the
low to the south. The 12z NAM though remains a northern outlier
at this time. For the latest official track and intensity
forecast, refer to the latest advisories from NHC.

&&

Long term /Monday through Friday/...
weak high pressure at the surface will build in from
southeastern Canada during this time frame, keeping the
forecast area dry Monday. With ridging aloft and increasing
heights, temperatures will be slightly warmer on Monday than
Sunday, just a couple of degrees above normal, in the lower to
middle 60s.

A weakening low pressure over the Great Lakes will send a warm
front north of the region Tuesday into early Tuesday night. The
associated cold front will quickly follow move Tuesday night
into Wednesday morning. A weak area of low pressure may develop
along the front, which could help to enhance the precipitation
as the system becomes negatively tilted. However there are
timing differences in when this system becomes negatively
tilted, and thus uncertainty in where and when any heavier
precipitation falls.

High pressure builds in and dominates the weather pattern with
dry weather to close the week. Temperatures will be a slightly
above normal for Thursday and Friday as well.

&&

Aviation /03z Saturday through Wednesday/...
high pressure will build in from the west overnight, and settle
across the region Saturday.

VFR. Northwest winds less than 10 kt overnight begin to back to the
west Saturday morning, and to the southwest in the afternoon,
remaining under 10 kt.



Outlook for 00z Sunday through Wednesday...
Saturday through Monday...mainly VFR. Chance of MVFR or lower
midday Sunday into Monday coastal terminals.
Tuesday...chance of showers with MVFR or lower cond. Gusty
winds possible Tuesday evening and overnight.
Wednesday...VFR.

&&

Marine...
ocean winds and gusts running a knot or so higher than forecast.
Otherwise no changes were made at this time.

High pressure builds across the waters through Saturday and
then to the east Saturday night. Tropical storm Nestor is
forecast to pass well south and east of the waters Sunday into
Sunday night. A strengthening NE flow ahead of the system could
potentially bring Small Craft Advisory conditions to the ocean waters Sunday
night.

Winds should remain below Small Craft Advisory criteria through Monday night.
However, there is a low chance of Small Craft Advisory seas lingering on the
ocean due to an easterly swell from Nestor. Gusts of to 25 to
30 kt are possible Tuesday night into Wednesday as a complex
frontal system impacts the area. Winds diminish Wednesday.

&&

Hydrology...
no hydrologic impacts are expected through the beginning of next
week. There is the potential for rainfall Tuesday into Tuesday
night. Exact rainfall amounts and potential impacts are
uncertain at this time.

&&

Equipment...
NYC National oceanic and atmospheric administration weather radio station kwo35 (162.55 mhz) remains off the
air.

&&

Okx watches/warnings/advisories...
CT...frost advisory from 3 am to 9 am EDT Saturday for ctz005>008.
New York...frost advisory from 3 am to 9 am EDT Saturday for nyz067>070.
New Jersey...frost advisory from 3 am to 9 am EDT Saturday for njz002-004-
103.
Marine...none.

&&

$$
Synopsis...jp/dw
near term...19/dw
short term...dw
long term...jp

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