FXUS61 KOKX 220010

Area Forecast Discussion
National Weather Service New York NY
710 PM EST Thu Jan 21 2021

Weak surface low pressure to the north sends several weak cold
fronts through the area by Friday night. High pressure builds
in from the west Saturday and Saturday night, and settles over
the region Sunday. The high weakens Monday as low pressure
approaches. The low passes south of the area Monday night and
Tuesday. High pressure returns for the middle of next week.


Winds have quickly decoupled and temperatures, especially in the
normally colder locations, have fallen quickly, and have been
adjusted several degrees lower for current conditions.
Increasing cloud cover, and increasing winds toward 06z as
another weak trough moves into the region will affect the
temperatures. And temperatures will likely rise again in the
colder locations as mixing occurs.

During the overnight period, the low pressure to the north of
the region will send another weak cold front through the area.
This may produce some clouds or some very light passing snow
showers for northern portions of the CWA which should end by


More of the same for Friday with a mix of clouds and sun and
the potential for some scattered flurries or sprinkles during
the afternoon as the low pressure sends yet another weak cold
front through the area. The additional mixing from daytime
heating and the cold upper-levels thanks to the departing trough
will allow for the development of a few convective showers of
snow or rain, especially during the afternoon. High temperatures
will be seasonable, generally in the low 40s.

Winds then shift more out of the NW by Friday night. The trough
shifts eastward as strong high pressure starts to build into
the area from the west. The pressure gradient tightens over the
area allowing brisk winds with gusty conditions developing
through Friday night and into early Saturday. Lows on Friday
night will generally be in the 20s with some of the coldest
spots dropping into the teens.


The northern stream will remain dominate and progressive
through the weekend and into Monday. A ridge builds into the
northeast and mid Atlantic coast by Sunday and then weakens as a
northern stream trough moves into eastern Canada Sunday night
and Monday.

A cold airmass will be in place for Saturday with a gusty
northwest flow as temperatures are expected to be a few degrees
below seasonal normals, with wind chills in the teens and lower
20s. Saturday night the gusty northwest flow gradually
diminishes as the cold airmass remains and temperatures will be
around 5 degrees below normal. Wind chill values will be mostly
in the single digits.

Meanwhile a southern stream shortwave moves out of the
southwest and quickly reaches the mid Atlantic coast Tuesday.
There is some phasing of the northern and southern stream
Tuesday into Tuesday night, however, the southern stream surface
low will dominate as the surface low reaches the Ohio Valley by
00Z Tuesday. There remain some differences in the guidance with
the timing and placement of another low developing off the mid
Atlantic coast Monday night and tracking east into the Atlantic
through Tuesday night. The trends remain to keep the low to the
south of the area as arctic high pressure to the north noses
down along the northeast coast. The ECMWF continues to be the
furtherest north with the low, while the GFS and Canadian keep
the precipitation shield across the southern portions of the
forecast area. Will keep the probabilities at chance throughout
the region for late Monday night through Tuesday. The airmass
remains cold and precipitation is expected to be in the form of
light snow.

Thereafter high pressure returns for later Tuesday into Thursday.
And the is a chance another low moves south of the area late


A weak cold front clears the area as it moves east early tonight. A
second cold front moves across Friday.

VFR. WSW-w around 10 kt or less through tonight. Gusts return late
Friday morning with W winds.

     NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Timing of gusts returning on Friday may be off by 1 to 3 hours.

.Friday Night...VFR. WNW 10-15g20kt.
.Saturday...VFR. NW gusts 25-30kt.
.Sunday...VFR. WNW 7-15g20kt.
.MONDAY...VFR. NW-N Light.
.TUESDAY...Chance of sub-vfr early in mixed precip or snow with NE
gusts 20-25kt.

Detailed information, including hourly TAF wind component forecasts,
can be found at: http:/www.weather.gov/zny/n90


The SCA for the eastern Long Island Sound, and the Long Island
bays was allowed to expire as winds have decoupled and fallen
well below 25 kt.

Small craft conditions on the oceans will persist through at
least Friday night with gusty winds over 25 kt becoming more
persistent through the day Friday and continuing into the night.
The SCA for the ocean was extended through Friday night.

Small craft conditions will be on going for Saturday across all
the forecast waters, with a strong northwest flow. There will
even be a chance of gales across the eastern ocean waters late
Saturday afternoon into the early evening.

High pressure will build in slowly from the west Saturday and
Saturday night, and wind gusts will be gradually diminishing below
SCA levels Saturday night through Sunday, with ocean seas below SCA
by late day Sunday. Sub advisory conditions are then expected across
all the waters from late Sunday night through Tuesday night as high
pressure gradually weakens with approaching low pressure to the


Mainly dry conditions are expected through the upcoming weekend.
No hydrologic concerns are anticipated through the middle of next


MARINE...Small Craft Advisory until 6 AM EST Saturday for ANZ350-353-



NWS OKX Office Area Forecast Discussion