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000
FXUS61 KOKX 181721
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
121 PM EDT Thu Apr 18 2024

.SYNOPSIS...
A weak wave of low pressure off the Mid Atlantic coast will keep
a frontal boundary well to the south today. High pressure will
briefly build in tonight into Friday before a cold front passes
through Friday night into Saturday morning. High pressure will
then follow from Saturday afternoon into early next week. A weak
frontal system will impact the region mid week.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Forecast remains on track with only minor changes needed.
Previous discussion follows.

Stacked low pressure over south central Canada will move slowly
ENE today, with high amplitude upper level ridging over the
Northeast and eastern Great Lakes region shifting eastward. At
the surface, a weak wave of low pressure off the Mid Atlantic
coast will keep a frontal boundary well to the south.

Chances for showers will continue today, but will slowly
diminish as high pressure noses in from SE Canada. This, coupled
with the incoming ridge aloft, will bring in just enough
subsidence to bring showers to an end over much of the area by
late afternoon. Showers may transition to just some drizzle
given abundant low level moisture with the maritime high
building in.

The high building in with the weak low to our south will mean a
strengthening easterly flow today. It does not look to be overly
windy, with sustained winds of 15 to 20 mph and gusts to 25 mph
along coastal sections this morning. Winds start to diminish
this afternoon as the high continues to nose into the region,
with the weak low well out to sea by this point.

The E flow will also mean cooler than normal temperatures, with
highs only in the upper 40s/lower 50s.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY/...
The sfc high will continue building in through Friday morning as
the upper ridge axis moves east, so dry conditions expected
through this time frame. A cold front associated with the low in
Canada will advance east, with an associated line of showers and
thunderstorms over the central Great Lakes region weakening as
it heads toward the eastern Great Lakes and then runs into the
high over the Northeast. So just chance to slight chance for
showers expected as this line moves through Friday night and
Saturday morning (lingering showers for eastern areas).

Temperatures recover somewhat on Friday, with highs in the 50s.
Even warmer conditions expected for Saturday with a westerly
flow and downsloping conditions expected after the passage of
the cold front. Went a couple of degrees above guidance for
highs, which are expected to be in the mid/upper 60s.

&&

.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
High pressure will continue to build into the region through the
second half of the weekend and remain in control of the
weather through Tuesday.

A 500mb trough then shifts through the Great Lakes on Tuesday
with an associated weak surface low and cold front. Rain
chances increase Tuesday night into Wednesday as this system
moves across the region. Drier weather returns for Thursday.

Temperatures just below normal on Sunday should rebound a few
degrees from Monday through Wednesday, to near or just above
normal. Temperatures fall back a degree or two below normal
behind the cold front on Thursday. Temperatures each day will be
in the upper 50s or 60s.

&&

.AVIATION /18Z THURSDAY THROUGH TUESDAY/...
Weak low pressure slowly moves southeast of the terminals
through this evening. High pressure builds in tonight through
Friday.

Mainly IFR conditions to start with some lingering -DZ.
Improvements to MVFR continue across southern CT terminal and
should begin working their way south and west across the rest
of the terminals through the remainder of the afternoon. Any
lingering -DZ should come to end by this evening. Improvement to
VFR is then likely first across southern CT early this evening
and then the rest of the terminals overnight. Amendments are
likely timing of the improving flight categories into tonight.

ENE-NE winds 10-15 kt with lingering gusts 20-25 kt early this
afternoon. Gusts may start becoming occasional around 20z and
should end this evening. NE winds under 10 kt are expected
overnight. Winds then shift to the E Friday morning and then SE
Friday afternoon, becoming 10-15 kt.

 ...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...

Improvement to MVFR may occur a few hours earlier than in TAF this
afternoon/early evening.

Gusts may be occasional or not occur at all this afternoon.

OUTLOOK FOR 18Z FRIDAY THROUGH TUESDAY...

Friday Afternoon-Night: VFR early, then MVFR or lower possible in
the evening and at night with showers possible.

Saturday: MVFR or lower with showers ending in the early morning,
becoming VFR. W-WNW wind gusts 15-20 kt possible late.

Sunday: VFR. W wind gusts 15-20 kt possible near coast in afternoon
and evening.

Monday-Tuesday: VFR.

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

&&

.MARINE...
Easterly winds will increase today with 25 to 30 kt gusts
expected on all waters except NY Harbor as high pressure builds
from the northeast.

Gusts diminish tonight as the high continues to build in. The
non ocean waters will likely drop below 25 kt early this evening
if not sooner. The ocean waters will likely have gusts over 25
kt hanging on into this evening.

Ocean seas build to 6 to 9 ft today and up to 5 ft on the far
ern Sound zone (western Block Island Sound), diminishing
thereafter but remaining above 5 ft on the ocean into daytime
Friday. Have extended SCA for the ocean into daytime Fri.

High pressure will continue to build early next week.
This should keep conditions at sub-advisory levels through at
least Tue night. Conditions may build back to SCA levels on Wed
with the next low pressure and associated cold front
to approach.

&&

.HYDROLOGY...
No hydrologic impacts expected attm.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory until 6 PM EDT this evening for ANZ331-
     332-335-340-345.
     Small Craft Advisory until 6 PM EDT Friday for ANZ350-353-355.

&&

$$

SYNOPSIS...BC/JP
NEAR TERM...BG/JP
SHORT TERM...JP
LONG TERM...BC
AVIATION...DS
MARINE...BC/JP
HYDROLOGY...BC/JP