NWS New York, NY wrote its last area forecast discussion before the first event at Feb 7, 9:58 AM EST, 1 hour 2 minutes earlier.
Area forecast discussion, Feb 7, 9:58 AM EST, 1 hour 2 minutes before
Area Forecast Discussion
National Weather Service New York NY
958 AM EST Fri Feb 7 2020
.SYNOPSIS...
Rapidly deepening low pressure will pass over the region through
early this afternoon, then track quickly to the northeast this
afternoon and tonight. High pressure builds over the region on
Saturday before moving off the New England coast on Sunday.
Unsettled weather then returns for the first half of the new
work week as a frontal system impacts the area.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
A warm front was beginning to lift to the northeast, and was
along the south shore of Long Island at 14Z. As low pressure
continues to rapidly deepen this morning the warm front is
expected to lift north. Record highs will be possible as the
warm air briefly moves into the region. Ahead of the front
visibilities remain low, with dense fog across most of Long
Island, and a dense fog advisory was issued through 16Z.
Elsewhere, a special weather statement remains for the fog,
locally dense.
There is good agreement that the low will pass just over the
Lower Hudson Valley around noon and lift northeast this evening.
Areas to the north and west will have the greatest chance of
seeing rain today, lower chances closer to the coast per latest
trends. QPF amounts will be light and generally under a quarter
of an inch.
The main story will be the strong winds that develop this
afternoon. With the deepening low just north or over northern
portions of the area (around 970 hpa), steep lapse rates,
strong pressure rises, 50+ kt winds in the mixed layer
increasing with height, will maintain the high wind warning for
coastal SE CT, and Suffolk County of Long Island, and the
earlier expansion westward into Nassau County and the 5
boroughs of New York City. MOS even indicating 30+ kt sustained
winds for a few cstl sites, which can be a good indicator as
well (March of 2010 comes to mind). Could see brief gusts (maybe
a 2-4 hour window) in excess of 60 mph, and will move up the
start time for the hazard to noon.
Elsewhere, the wind advisory remains in effect, but cannot rule out
a gust to 60 mph. However, lower confidence in this, with 45 to 55
mph gusts more likely.
The timeframe for these damaging winds is from noon through the
remainder of the afternoon. Winds remain quite gusty into the
evening, but winds of those magnitudes are not expected as the
evening progresses.
High temperatures will be in the 40s across the interior and in
the 50s along the coast, NYC and NE NJ.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
Winds remain breezy overnight with strong cold advection behind
the cold front. Lows will fall into the teens and 20s across
the area under a clearing sky.
High pressure pushes down from Canada on Saturday with
diminishing winds. Some clouds will develop in the late
afternoon in response to a passing shortwave but should overall
be a mostly sunny day. It is possible that there will be enough
moisture in place to support a few snow showers, but have kept a
dry forecast for now. Highs will only be in the 30s to around
40 degrees.
&&
.LONG TERM /SUNDAY THROUGH THURSDAY/...
The next system of interest begins to approach the area Sunday
night as an upper trough and associated surface low cross the
Great Lakes. Precipitation chances will increase Sunday night
into Monday morning, with precipitation continuing through much
of the day on Monday ahead of the approaching cold front. While
models are generally in good agreement with the idea of a
frontal passage occurring Monday evening, solutions begin to
diverge thereafter as the front stalls south of the area and
additional waves of low pressure ride northward along the
boundary. This will result in a period of unsettled weather
Tuesday into Wednesday before the area briefly dries out ahead
of the next system approaching for Thursday.
After near normal temperatures on Saturday and Sunday, temperatures
will return to above normal for Monday through Thursday, with highs
generally in the 40s and lows generally in the 30s. This will result
in the vast majority of the precipitation during the new work week
falling as rain, although periods of snow or a rain/snow mix are
possible at times inland.
&&
.AVIATION /15Z FRIDAY THROUGH TUESDAY/...
A wave of low pressure will deepen and track northwest of most
of the terminals through today and will move well northeast of
the region tonight.
LIFR/VLIFR conditions this morning in fog with more MVFR late
this morning as SE-S winds increase and become gusty. There
will be some intermittent rain as well. Expecting eventual
improvement to VFR this afternoon.
Winds become more southerly, SE to S this morning, increasing
to 10 to 15 kt. Then southwesterly to westerly winds increase
rapidly late this morning into the afternoon, 20-30 kt with
gusts 40 to 50 kt, with the highest winds across relatively more
southeastern terminals (KJFK, KISP, KGON). LLWS this morning,
with 40-45 kt winds at 2 kft increasing to 50-60 kt at 2kft by
late morning. LLWS lingers east of NYC terminals this afternoon,
SW winds of 55-65 kt at 2kft.
NY Metro Enhanced Aviation Weather Support...
Detailed information, including hourly TAF wind component fcsts,
can be found at: http:/weather.gov/zny/n90
KJFK TAF Comments: Amendments can be expected to refine timing
of any categorical changes and wind gusts changes.
The afternoon KJFK haze potential forecast is GREEN, which implies
slant range visibility P6SM outside of cloud.
KLGA TAF Comments: Amendments can be expected to refine timing
of any categorical changes and wind gusts changes.
The afternoon KLGA haze potential forecast is GREEN, which implies
slant range visibility P6SM outside of cloud.
KEWR TAF Comments: Amendments can be expected to refine timing
of any categorical changes and wind gusts changes.
The afternoon KEWR haze potential forecast is GREEN, which implies
slant range visibility P6SM outside of cloud.
KTEB TAF Comments: Amendments can be expected to refine timing
of any categorical changes and wind gusts changes.
KHPN TAF Comments: Amendments can be expected to refine timing
of any categorical changes and wind gusts changes.
KISP TAF Comments: Amendments can be expected to refine timing
of any categorical changes and wind gusts changes.
.OUTLOOK FOR 12Z SATURDAY THROUGH TUESDAY...
.Saturday...Mainly VFR. NW winds around 15 kt, gusting 20-25
kt. Winds diminish at night.
.Sunday....Slight chance of snow showers, becoming rain showers
along the coast in the afternoon. Chance for snow showers
inland at night with a chance of rain showers for the coast at
night. MVFR to IFR possible.
.Monday...Chance of snow early Monday morning and late Monday
night near KSWF and KHPN as well as CT terminals with MVFR/IFR
possible. Otherwise, a chance of light rain with MVFR possible.
.Tuesday...Chance of rain/snow mix across interior terminals
with MVFR/IFR possible early. Otherwise, A chance of light
rain with MVFR possible.
&&
.MARINE...
Storm Warning remains up for all waters. Do expect gusts to
increase to 50 kt by afternoon, with 60 kt gusts possible over
the eastern ocean waters this afternoon.
This is due to rapidly deepening low pressure that passes just north
of the waters by early afternoon, and an atmosphere that will
support these gusts.
Strong gusty winds continue tonight as well, but diminish slowly as
the night wears on from gales to SCA. Seas build through the day,
then will slowly subside tonight and into the weekend as the storms
pulls away.
Winds and seas will continue to decrease during the day on Saturday
as high pressure builds across the area, with sub-SCA conditions
returning to all waters on Sunday. Seas then increase to 5 ft on the
ocean again on Monday and gusts approach 25 kt ahead of an
approaching cold front. Seas will remain elevated into the day on
Tuesday as the front lingers south of the waters.
&&
.HYDROLOGY...
No hydrologic impacts are expected.
At this time, precipitation amounts with the frontal system
next week are generally expected to remain under 1 inch.
&&
.TIDES/COASTAL FLOODING...
Increasing east flow early this morning has pushed water levels
to minor coastal flood thresholds over the western south shore
back bays of LI (Nassau and Queens). This is also expected
across the western LI Sound. As such, a cstl flood statement
remains in effect.
Gale to Storm force winds this afternoon/night will likely build
breaking surf to 10 to 14 ft. Fortunately water levels are expected
to be low, limiting dune impacts, but areas of Atlantic ocean beach
erosion and flooding is possible.
Elsewhere, could be some minor splashover coastal impacts into
eastern Great South Bay from wave action and potential sloshing
of waters eastward after wind shift to SW/W for the evening
high tide, but not confident as the evening high tide will be
quite low.
Similarly, waves should build as high as 5-8 ft across Central and
Eastern LI Sound this afternoon/evening, which could cause some
localized minor beach erosion issue/wave splashover issue during the
evening high tide along the north shore of Suffolk County.
&&
.EQUIPMENT...
NYC NOAA Weather Radio Station KWO35 (162.55 MHz) is still
operating at reduced power.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...High Wind Warning until 7 PM EST this evening for CTZ011-012.
Wind Advisory until 7 PM EST this evening for CTZ005>010.
NY...High Wind Warning until 7 PM EST this evening for NYZ072>075-
078>081-176>179.
Dense Fog Advisory until 11 AM EST this morning for NYZ078>081-
177-179.
Wind Advisory until 7 PM EST this evening for NYZ067>071.
NJ...Wind Advisory until 7 PM EST this evening for NJZ002-004-006-
103>108.
MARINE...Storm Warning until 7 PM EST this evening for ANZ330-335-338-
340-345-350-353-355.
&&
SYNOPSIS...CB/JC
NEAR TERM...19
SHORT TERM...CB
LONG TERM...FEB
AVIATION...JC
MARINE...19
HYDROLOGY...CB
TIDES/COASTAL FLOODING...
EQUIPMENT...