Area Forecast Discussion
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FXUS61 KOKX 142105
Area Forecast Discussion
National Weather Service New York NY
405 PM EST Sat Jan 14 2017
A wave of low pressure passes to the south and east tonight. High
pressure builds Sunday and Sunday night. High pressure across the
region Monday drifts offshore Monday afternoon into Monday night.
A warm front approaches from the west Tuesday and slowly moves in
Tuesday into Tuesday night. It moves through and to the north of
the area late Tuesday night with a cold front to follow for early
Wednesday. Weak high pressure builds in from the west from mid to
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Very dry atmosphere earlier has moistened quickly across western
Warm air advection, mid level lift aided by approach and passage of
H3 jet will allow for passing light snow to occur into this evening.
Pops will be layered from likely NYC metro and Long Island, with
chance to slight chance as you head north across the interior.
Any light snow will product a coating to a half an inch.
A wave of low pressure rides along a stationary frontal boundary to
the south overnight.
Temperatures will fall this evening especially as snow develops,
then fall further late tonight as skies clear and NW winds
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/...
Initial shortwave aloft passes well east, with a general W/NW
flow expected aloft through this time frame. Surface high pressure
builds across the Great Lakes Region/Ohio Valley toward and over
the area Sunday night.
Dry weather, with generally clear skies, can be expected.
Temperatures will rise to the upper 30s to middle 40s, slightly
above normal. A NW breeze during the day diminishes at night as the
pressure gradient relaxes. Good radiational cooling conditions
prevail, with low temperatures ranging from near 30 in NYC, to the
teens across the normally colder spots, interior and pine barrens
of eastern Long Island.
.LONG TERM /MONDAY THROUGH SATURDAY/...
Upper levels exhibit split jet structure with subtropical jet
approaching the region Monday night into Tuesday. This jet amplifies
Tuesday night into Wednesday with local region being in the left
front quadrant of enhanced synoptic lift. This jet will then become
more suppressed to the south of the region late Wednesday through
the end of the week. Upper and mid levels show slight ridging Monday
into Tuesday and then a nearly steady geopotential tendency Tuesday
afternoon into Tuesday evening before becoming negative Tuesday
night through Wednesday. Weak ridging builds in slowly from the west
At the surface, high pressure will be across the region and will
present an airmass with slightly above normal temperature under a
mostly sunny sky and light winds. The sky remains mostly clear to
start Monday night and winds remain light so radiational cooling
will be optimal the first half of the night. Then, clouds increase
as a warm front approaches with associated isentropic lift. The
warm air advection aloft will set temperatures a few degrees above
freezing within the 1kft to 5kft layer and with surface
temperatures for most locations Monday night into early Tuesday,
if precipitation arrives early enough, this would be in the form
of freezing rain. Later on Tuesday by mid to late morning,
temperatures rise with light onshore flow and any freezing rain
would change to plain rain. The progression of this would be from
south to north with interior locations being last to change to
plain rain. Temperatures are expected to rise into the upper 30s
to lower 40s Tuesday. Not much of a drop in temperatures Tuesday
night as warm front works its way through the region. Rain
continues and then tapers off late Wednesday into Wednesday night
from west to east behind the cold front.
Low pressure slowly moves northeast of the region eventually into
the Canadian Maritimes by end of the week. Weak high pressure builds
in from the west. Dry weather expected Wednesday night through end
of the week.
Temperatures are near normal Tuesday and above normal Tuesday night
through the rest of the forecast period.
.AVIATION /21Z SATURDAY THROUGH THURSDAY/...
A stationary front will remain south of the region through tonight.
High pressure will build in from the west on Sunday.
Snow, mainly light, will continue this evening. Snowfall rates are
expected to be a half inch per hour or less.
Total snowfall accumulations, due to the light rates, are not
expected to exceed around a half inch at this time. Only flurries
may occur at Newburgh.
After the initial snow early this evening, there is a chance that
visibilities are better than the TAFs indicate.
Ceilings have been kept at 1000 ft in the snow, however, pockets of
a few hundred feet are likely in heavier snow.
VFR returns quickly after the snow ends, and remains through the
remainder of the TAF period.
Light flow, generally at or below 6 kt, can be expected through 6-
10Z. The flow will increase slightly out of the northwest by Sunday
.OUTLOOK FOR 18Z SUNDAY THROUGH THURSDAY...
.Rest of Sunday...VFR.
.Monday night...Rain will attempt to develop resulting in MVFR or
lower. If precipitation does develop, freezing rain is possible at
.Tuesday...Rain with IFR.
Light south flow this evening will turn to the NW behind a
passing wave of low pressure and ahead of building high pressure
later tonight and through Sunday.
The winds increase late tonight and into Sunday before
diminishing. At this time, expect winds to remain below 25 KTs, so
no headlines planned.
Seas through Sunday night remain 1 ft or less across the non ocean
waters, and less than 3 feet across the ocean waters.
SCA probable on the ocean Wed through Thu with otherwise sub SCA
conditions expected for other marine area and for other time
periods regarding the long term forecast marine period Mon
No significant precipitation is forecast through the remainder of
the weekend. No hydrologic impacts are expected.