Area Forecast Discussion
Issued by NWS Upton, NY

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FXUS61 KOKX 260903

Area Forecast Discussion
National Weather Service New York NY
503 AM EDT Wed Oct 26 2016

High pressure briefly builds down from Southeast Canada today
through much of tonight. A frontal system approaches Thursday and
moves across Thursday night with the attached low deepening
towards Friday morning. High pressure then builds back in on
Friday and lasts into Saturday. A weak cold front moves through
Saturday night, followed by a weak low passage to our south Sunday
night. High pressure then returns for Monday and Tuesday.


Region under the influence of high pressure with light winds and
clearing conditions, allowing for good radiaitonal cooling going
into daybreak. Freeze warning continues across the interior with
the forecast on track.

There will be some ridging aloft but the core of an upper level
NW jet streak remains above the region today. High pressure at the
surface builds down from Southeast Canada allowing for a weaker
pressure gradient.

Dry weather is expected today with a cool day expected. The
vertical mixing will be less with less gusty winds. The remaining
cyclonic flow aloft will keep a cooler than normal airmass in
place. Highs were taken using a blend of MAV and MET guidance,
with a range from the upper 40s to lower 50s.


The jet streak exits tonight into Thursday but another one moves
in Thursday night and the local region will be right in the left
front quad of that upper level jet streak. The mid levels become
more zonal tonight into Thursday before an amplifying shortwave
trough approaches Thursday night. These features, with the left
front quad and approaching shortwave, will enhance synoptic lift.

Expecting dry weather to continue through much of tonight and then
widespread precipitation moves across ahead of a frontal system
for Thursday through Thursday Night, mainly in the form of rain.
The aforementioned synoptic forcing will allow for periods of
moderate rain and perhaps locally heavy rain at times.

Uncertainty at the onset Thursday with regards to timing and
precip type across the interior. Soundings seem more of a
rain/snow scenario versus freezing rain. Made freezing rain just a

The forcing initially Thursday will be the warm air advection
aloft evident with the isentropic lift. However, the model
soundings are not showing much of a warm nose around 5kft above
the surface. The temperatures gets to near or just above freezing
near 5kft, with surface temperatures right near to just below
freezing Thursday morning. This portends to more of a snow and
sleet scenario without complete melting of falling ice crystals as
there will be a greater area below freezing within the boundary

Snow accumulations across parts of the interior including portions
of Northeast NJ, the Lower Hudson Valley and SW Connecticut could
reach 1 to possibly 2 inches of snow. The soundings are actually
showing sufficient icing with moist vertical profiles in between
the -10 to -30 degree C levels. This is portraying the moisture
coming in first tonight as mid and high levels clouds tonight and
then gradually lowering and thickening towards early Thursday with
increasing low level moisture thereafter through much of Thursday

Cooler than normal temperatures continue tonight and Thursday.
The rain and clouds Thursday night will keep temperatures a
smaller range across the region and a little above normal.


High pressure builds in during Friday with breezy conditions. The
shortwave aloft will already be to the east and moisture will be
limited, so not expecting any instability showers and will continue
with a dry forecast. High temperatures will be slightly below normal.

The high pressure ridge shifts through the region early Saturday
morning. Looks like clouds will increase ahead of an approaching
cold front, but it still could be at least partly sunny for a good
amount of the day. Will keep in a slight chance of an afternoon
shower well north and west, but it looks like moisture is lacking
and wouldn`t be surprised if it turns out to be dry all day there.
High temps slightly above normal.

The cold front passes through Saturday night with weak ridging
behind it on Sunday. ECMWF has trended toward GFS during this period
in that only a weak low is progged to approach us, eventually
passing us to the south Sunday night. Some lift will be provided
with a shortwave aloft, so will still at least go with a slight of
showers Sunday/Sunday night.

High pressure builds in Monday, lingers into Tuesday, then is
followed by an approaching cold front late Tuesday night. Once
again, moisture is lacking, so will keep this entire period dry.


High pressure slowly builds into the region today.

VFR through the next 24 hours.

Winds will generally be from the Northwest today (310-340) around
10 kt. Will continue to carry gusts into the middle and upper
teens, however the gusts may be more occasional that frequent
today. Gusts diminish late in the day, and speeds fall to 10 kt or
less overnight.

Clouds increase and lower late for the 30 hour tafs sites.

     NY Metro Enhanced Aviation Weather Support...

Detailed information, including hourly TAF wind component forecasts,
can be found at: http:/

KJFK TAF Comments: Wind gusts may be more occasional than frequent
today. High confidence VFR.

KLGA TAF Comments: Wind gusts may be more occasional than
frequent today. High confidence VFR.

KEWR TAF Comments: Wind gusts may be more occasional than
frequent today. High confidence VFR.

The afternoon KEWR haze potential forecast is GREEN...which implies
slant range visibility 7SM or greater outside of cloud.

KTEB TAF Comments: Wind gusts may be more occasional than
frequent today. High confidence VFR.

KHPN TAF Comments: Wind gusts may be more occasional than
frequent today. High confidence VFR.

KISP TAF Comments: Wind gusts may be more occasional than
frequent today. High confidence VFR.

.Thursday...MVFR or lower possible in rain. Potential for a wintry
mix across the interior before 15Z. Southerly winds.
.Friday...VFR with strong northwest flow behind a cold front.
Gusts to at least 25 kt are expected at this time.
.Saturday and Sunday...VFR with southwest flow possible.


SCA conditions linger on the ocean and eastern waters into early
this morning, due to wind gusts. Thereafter, the gusts will be on
a downward trend with decreasing winds in the boundary layer as
the pressure gradient lowers. High pressure builds down from
Southeast Canada this afternoon through tonight. The sub SCA
conditions remain through early Thursday and then increase again
ahead of a frontal system Thursday afternoon with possible SCA
conditions late. SCA becomes more probable Thursday night as the
frontal system moves through and the low with this system deepens
towards Friday morning, increasing the pressure gradient and
therefore the winds.

The pressure gradient tightens as high pressure builds in behind the
departing storm. Looks like gales will be possible on the ocean and
at least over the eastern Sound and Bays as well. In any case, at
least a SCA will likely be needed eventually. Winds and seas then
diminish Friday night into Saturday as the high pressure ridge moves
in. Looks like sub-SCA conditions will be on all waters by Saturday

The rest of the forecast period likely remains under advisory
criteria, however there is chance of gusts around 25 kt on the ocean
Saturday afternoon and evening as the pressure gradient tightens
ahead of an approaching cold front.


Weather remains dry through tonight and then widespread
precipitation, mostly rain is expected Thursday through Thursday
night. This will amount to around 1 to 1.25 inch. Locally higher
amounts will be possible. So there will be possible localized
minor flooding and ponding of water but no other hydrologic
problems are anticipated.

Widespread significant precipitation is not expected for the rest
of the forecast period.


CT...Freeze Warning until 9 AM EDT this morning for CTZ005>008.
NY...Freeze Warning until 9 AM EDT this morning for NYZ068>070.
NJ...Freeze Warning until 9 AM EDT this morning for NJZ002-004-103-
MARINE...Small Craft Advisory until 6 AM EDT early this morning for
     Small Craft Advisory until 8 AM EDT this morning for ANZ350-


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