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fxus61 kokx 121945 
afdokx

Area forecast discussion
National Weather Service New York New York
issued by National Weather Service Taunton Massachusetts
245 PM EST Tue Nov 12 2019

Synopsis...
strong and gusty northwest winds, along with colder temperatures
will be the main weather story tonight. A few flurries are
possible until early this evening. High pressure builds in from
the west through Wednesday, then moves offshore on Thursday as
a weak warm front passes through. This will be followed up by
another cold frontal passage Friday night and high pressure next
weekend. Low pressure may impact the area late Sunday into the
first part of next week.

&&

Near term /through tonight/...
245 PM update...

Mother nature is following the forecast pretty well. Cold front
has pretty much blasted through the area. The only precipitation
left across the area is primarly across eastern Long Island and
extreme southeast CT. Radar still indicates a band of light
returns all the way west to a line from northwest CT, through
the lower Hudson Valley and into northwest New Jersey. Most of this
precipitation is evaporating before it reaches the ground, but
what does make it down are a few light snow flurries. No
accumulations are expected. Temperatures have been steadily
falling with the freezing line now knocking at the door of the
immediate NYC area. Winds have been gusting generally in the
20-30 mph range, but have noted a few higher gusts in the last
couple of hours (36 mph at bdr and LGA, 35 mph at JFK and isp).
Only minor tweaks made to the forecast based on latest radar and
temperature trends.

That leaves US with light precipitation across the far east
ending in the next couple of hours. Need to wait for a weak
upper level impulse currently over the Delaware-Maryland-Virginia region to pass
by. Primarily rain, but it will end as a little bit of snow.
Again, no accumulations are expected as air and ground
temperatures will still be above freezing before all the
precipition ends. Skies will be rapidly clear during the
evening. Lots of upstream cold air advection strato-cumulus that
could drift into northwestern areas, but as the air comes down
from the higher terrain, those clouds will disipate before
getting too far east.

All guidance still on track for overnight lows to drop into
record territory -- teens north and west, lower 20s across the
Metro area and Long Island. This is courtesy of -17 to -19c air
at 850mb (which is the coldest air we've seen at that level
this time of year in at least the past 30 years). Don't want to
Forget the winds. They'll remain gusty all night, resulting in
wind chills dropping down into the lower single digits almost
everywhere come daybreak Wednesday.

The winds and very dry air coming in should evaporate most of
the moisture off surfaces, and negate any widespread or
significant issues with black ice later tonight and tomorrow
morning.

&&

Short term /Wednesday/...
245 PM update...

No big changes made to the forecast for tomorrow. The core of
the cold air aloft will be on top of US. With 925mb temperatures
in the -9 to -11c range, that suggests Max temperatures at the
ground will be right around freezing. This would set new record
low maximum temperatures for the day. With very dry air
(dewpoints in the single digits above 0f), we should see wall to
wall sunshine, even though it won't do much to take away the
chill. Gusty winds during the morning will begin to subside by
the afternoon.

&&

Long term /Wednesday night through Tuesday/...
245pm update...

No changes made to the extended forecast. Previous discussion
below

High pressure will build over the area Wednesday night.
Light winds and clear skies Wednesday night will allow for good
radiational cooling, as temperatures fall into the teens and
20s.

The high slides offshore on Thursday, allowing winds to become more
southerly as a warm front lifts north across the region.
Temperatures on Thursday will reach the upper 30s and 40s.

Another cold frontal passage is on track for the end of the week,
but the airmass this time around will not be as cold as what we see
over the next two days. Low pressure may impact the region late
Sunday into early next week as an upper low along the southeast
coast gets drawn northward ahead of an upper trough moving across
the Mississippi Valley. Temperatures moderate Sunday through
Tuesday.

&&

Aviation /19z Tuesday through Sunday/...
strong cold front has moved east of the region, with primarily
light precipitation still remaining behind. The airmass has
gotten cold enough that from about the NYC area west, we are
seeing a little bit of -sn (flurries/very light snow) activity.
Still warm enough across the eastern portion (mainly southeast CT and
long island) that we have -ra. Over the next 6 hours, the
precipitation will shift eastward and be out of the region.
Until then, there is a chance of a little bit of -sn. Won't be
significant enough to cause any visibility reductions, nor any
accumulation on runways or other surfaces.

Ceilings are still MVFR to spots of IFR across eastern areas,
but in general we are VFR most everywhere else, with ceilings
somewhere in the 5000-8000ft range. All guidance suggests that
by 00z we will be rid of ceilings everywhere, with just some
scattered low/mid level clouds.

Primary weather issue will be the continued northwest surface winds,
which will continue to gust 20-30kt (possibly just above 30kt at
times) overnight.

New York Metro enhanced aviation weather support...

Detailed information, including hourly taf wind component forecasts,
can be found at: http:/www.Weather.Gov/zny/n90

Kjfk taf comments: ceilings could persist a little beyond what
is forecast. Any snow is not expected to have a significant
impact on visibility.

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

Klga taf comments: ceilings could persist a little beyond what
is forecast. Any snow is not expected to have a significant
impact on visibility.

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

Kewr taf comments: ceilings could persist a little beyond what
is forecast. Any snow is not expected to have a significant
impact on visibility.

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

Kteb taf comments: ceilings could persist a little beyond what
is forecast. Any snow is not expected to have a significant
impact on visibility.

Khpn taf comments: ceilings could persist a little beyond what
is forecast. Any snow is not expected to have a significant
impact on visibility.

Kisp taf comments:ceilings could persist a little beyond what
is forecast. Any snow is not expected to have a significant
impact on visibility.

Outlook for 18z Wednesday through Sunday...
Wednesday-Friday...VFR. Northwest winds diminishing below 10kt by
late Wednesday. Light southeast then SW winds Thursday into Friday.
Saturday-Sunday...VFR. North-NE gusts 15-20 kt Saturday.

&&

Marine...
245 PM update...

No significant changes to the forecast. Still looking at strong
and gusty northwest winds that will continue all night. May end
up being on the marginal side for the 35kt threshold in New York
Harbor and far western end of Long Island Sound, but figured it
would be close enough as the relatively warm waters will enhance
mixing of the lower atmosphere, resulting in higher potential
to see the stronger winds a couple of thousand feet up to make
it's way down to the surface than compared to the adjacent land
areas.

Seas will reach 5 to 9 ft across the ocean waters, and 3 to 5
ft for the eastern sound. Winds and gusts will begin diminishing
Wednesday morning. As that happens, waves will also start to
subside, with marine conditions expected to fall below Small Craft Advisory
criteria on the ocean by late Wednesday afternoon.

Sub-Small Craft Advisory conditions are forecast Wednesday night into Friday. A cold
frontal passage Friday night will result in northerly winds, which
will likely bring Small Craft Advisory conditions back to the area waters.

&&

Hydrology...
no hydrologic impacts expected through the period.

&&

Climate...
record lows for Tuesday November 12th
temperature | year
nyc| 26 | 1926
jfk| 29 | 2017
lga| 32 | 2013
ewr| 28 | 2017
isp| 25 | 2001
bdr| 28 | 1957, 2013

Record minimum high temperatures for Wednesday November 13th
temperature | year
nyc| 33 | 1911
jfk| 41 | 2013
lga| 39 | 1977
ewr| 41 | 2013
isp| 39 | 2013
bdr| 38 | 1995

Record lows for Wednesday November 13th
temperature | year
nyc| 24 | 1986
jfk| 25 | 1986
lga| 26 | 1986
ewr| 24 | 1986
isp| 24 | 2001
bdr| 23 | 1986

&&

Equipment...
NYC National oceanic and atmospheric administration weather radio station kwo35 (162.55 mhz) is operating
at reduced power until further notice.

&&

Okx watches/warnings/advisories...
CT...none.
New York...none.
New Jersey...none.
Marine...Gale Warning until 6 am EST Wednesday for anz330-335-338-340-
345-350-353-355.

&&

$$
Synopsis...BC/jp
near term...Nash
short term...Nash
long term...British Columbia

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