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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KOKX 260150
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
950 PM EDT Wed Apr 25 2018

.SYNOPSIS...
Low pressure over the Delmarva region will ride up across the
area tonight, with a trailing cold front also passing through
late. The low will move into New England on Thursday. Another
low will move through on Friday, followed by a cold frontal
passage late Saturday. High pressure will then be in control
early to mid next week.

&&

.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
Showers are still likely for the late evening hours across
eastern LI and SE CT as moisture continues to stream north ahead
of a cold front. Expecting at least a chance of showers
elsewhere as this front slowly pushes east through the tri-state
area. Cannot rule out an isolated thunderstorm with some
elevated instability and lift. Will continue to address patchy
dense fog with SPSs for now. Best chances of widespread dense
fog would have been eastern LI and CT as these spots will be
last to have the cold front passage, however showers here have
been mixing out dense fog as they pass through. Still cannot
rule out the need for an advisory for these eastern zones as
winds will be light with a lack of turbulent mixing at the top
of the boundary layer.

Light winds aloft could lead to slow-moving heavy downpours, but
this so far would appear to remain offshore to our south - just
something to keep an eye on until the cold front moves through.

Fcst low temps tonight are on the warmer side of the MOS
envelope, in the upper 40s and lower 50s.

&&

.SHORT TERM /6 AM THURSDAY MORNING THROUGH THURSDAY NIGHT/...
Gusty WNW flow expected along with mostly sunny skies for the
most part after the mid level shortwave passes through. A closed
mid level low passing just to the north may help provide enough
lift for sct-bkn Cu development in the afternoon, more so
inland.

With downslope flow and mixing to between 875-850 mb expect
high temps to approach 70 in NE NJ and rise well into the 60s
most elsewhere.

Thu night should start mostly clear, then become mostly cloudy
overnight as another low begins to approach from the SW. Low
temps should be in the 40s and lower 50s per MOS blend.

&&

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
Models in good agreement with the closed low over the central
Plains tracking eastward through the deep South on Thursday.
This then lifts north toward the region Friday ahead of the next
northern stream trough digging into the Mississippi River
Valley on Thursday. At the surface, associated low pressure
lifts northeast towards the region on Friday. This is a
progressive system, with what looks like a quick hit of moderate
rain (1/4 to 3/4 inch, locally 1 inch). Still uncertainty on
where the axis of the heaviest rain will be, due to differences
in track of low pressure and consequently placement of best
lift/instability axis.

Models then in general agreement with partial phasing of the
southern energy and digging northern stream trough to develop
a deep trough over the Great lakes into the NE US this weekend.
Some spread in intensity/amplitude of this trough, but general
consensus on its axis moving through Sunday. At the surface, an
associated cold front moves through late Sat/Sat evening, with a
couple of weak troughs moving through Sunday. Seasonable temps
on Saturday in waa ahead of the front, dropping back down to a
few degrees below seasonable on Sunday with cold pool and
instability cloud cover.

In its wake, deep layered ridging builds in for early next week,
with potential for unseasonable warmth by midweek as ridging
takes a Bermuda position. Temps moderate to seasonable on Monday
and then above seasonable on Tuesday. Potential for the first
real warm spell of the season mid to late week, with high temps
in the 80s for NYC/NJ metro and Interior, and well into the 70s
along the coast.

&&

.AVIATION /02Z THURSDAY THROUGH MONDAY/...
Low pressure tracks from the Mid-Atlantic coast this evening to
the Canadian Maritime Provinces by early Thursday evening.

IFR or less through at least 07Z. Light rain/drizzle continues
through then, with some pockets of moderate rain possible.
Outside of times when areas receive moderate rain, expect
widespread fog to develop this evening. Conditions should
improve to MVFR 8-11Z from W to E, then to VFR from 10-13Z from
W to E as well.

Light and variable winds into the early morning hours. Winds
become W-WNW 8-11Z from W to E. Wind speeds increase to 10-15KT
during the morning push, with gusts of 15-20KT developing
towards the end of the morning push. Winds back to the WSW-SW at
KJFK and KISP Thursday afternoon, remaining W to WNW elsewhere.
Wind gusts should abate late Thursday afternoon/early Thursday
evening.

 ...NY 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: High confidence IFR or less through 07Z.

KLGA TAF Comments: High confidence IFR or less through 07Z.

KEWR TAF Comments: High confidence IFR or less through 07Z.

KTEB TAF Comments: High confidence IFR or less through 07Z.

KHPN TAF Comments: High confidence IFR or less through 08Z.

KISP TAF Comments: High confidence IFR or less through 08Z.

.OUTLOOK FOR 00Z FRIDAY THROUGH MONDAY...
.Thursday night...VFR.
.Friday...MVFR or lower possible in rain.
.Friday night-Saturday night. MVFR possible in isolated-
scattered showers, otherwise VFR.
.Sunday-Monday...VFR. W-NW winds G15-25KT possible.

&&

.MARINE...
SCA remains in effect for the ocean for elevated seas.

Marine dense fog advy issued for all waters for tonight as low
pressure moves across and vsby lowers to less than 1 nm in most
places. Cold fropa will shift winds to the W-NW and quickly
scour out the fog late tonight into early thu morning.

SCA seas likely continue on the ocean waters into Saturday
night, possibly lingering into Sunday, due to lingering SE
swells from the mid week system, and then added contribution of
wind waves and southerly swells from a quick moving low on
Friday and winds ahead and behind cold frontal passage Sat eve.

Marginal SCA winds possible, mainly eastern waters Friday
aft/eve on the eastern flank of low pressure.

&&

.HYDROLOGY...
Today`s rainfall has not been causing any hydrologic impact.

QPF 1/4 to 3/4 inch possible Friday with a quick moving low. No
hydrologic issues anticipated.

&&

.EQUIPMENT...
NYC NOAA Weather Radio Station KWO-35 (162.55 MHz) remains off
the air.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Dense Fog Advisory until 6 AM EDT Thursday for ANZ330-335-338-
     340-345-350-353-355.
     Small Craft Advisory until 6 AM EDT Friday for ANZ350-353-355.

&&

$$
SYNOPSIS...Goodman/NV
NEAR TERM...JC/Goodman
SHORT TERM...Goodman
LONG TERM...NV
AVIATION...Maloit
MARINE...Goodman/NV
HYDROLOGY...Goodman/NV
EQUIPMENT...