000
FXUS61 KOKX 132101 CCA
AFDOKX
Area Forecast Discussion...CORRECTED
National Weather Service New York NY
501 PM EDT Sat Apr 13 2024
.SYNOPSIS...
Low pressure deepens as it moves farther east within Southeast
Canada. High pressure briefly builds in from the south late tonight
into Sunday before another low pressure system approaches late
Sunday afternoon. This system moves through Sunday night. High
pressure returns for Monday and Tuesday. A slow moving warm
front then approaches the area from the southwest Wednesday
followed by a cold front late in the week as low pressure passes
well to the northwest.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
Upper level trough moves across this evening before shifting
east of the area overnight. Low pressure at the surface
strengthens within Southeast Canada as it continues to move east.
Gusty winds along with isolated to scattered rain shower
activity is expected to continue into early this evening. Gusty
winds due to the steep pressure gradient and cold air advection
will linger well into this evening. Surface wind gusts were
increased from previous forecast after noting some higher lapse
rates from 900 to 850mb. Gusts up to 30 to 40 mph are expected
along much of the coast. BUFKIT shows enhanced mixing and top of
the mixed layer would be even higher with gusts up to near 45
to 50 mph. However, chances of realizing those higher gusts will
be low as diurnal heating will be lessening for this evening so
would expect more mean boundary layer winds to get mixed down
as opposed to near the top of the mixed layer.
Overnight, ridging trend aloft. Surface high pressure builds in
late into early Sunday morning. Drier conditions along with a
weakening pressure gradient so gusts are expected to lower late
tonight as well.
Min temperatures forecast range from upper 30s to upper 40s.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH SUNDAY NIGHT/...
-- Changed Discussion --
Brief high pressure and continued ridging in the morning Sunday.
Day starts out mostly sunny but with increasing clouds in the
afternoon ahead of the next low pressure system, quickly moving
and developing within the Northeast from the Great Lakes. Low
level winds become more southerly Sunday, eventually becoming
gusty in the afternoon into the evening as a warm front moves
north of the region. This will increase low level warm air
advection.
The rapidly evolving and moving low pressure area will increase
vertical forcing and shear. This will be ahead of an associated
cold front. Instability increases in the low levels as well.
Showers will become likely for interior and parts of the western
area. There will be a chance for thunderstorms as well, some of
which could become strong to severe with strong to damaging
winds as the primary threat especially for more western and
interior areas. The main timing of this precipitation is from late
Sunday afternoon through Sunday evening.
Max temperatures Sunday are forecast to be upper 50s to around
70 with higher end of the range towards Lower Hudson Valley and
Northeast NJ. Min temperatures Sunday night are forecast to be
in the upper 40s to mid 50s.
Overall confidence is low on the forecast with the thunderstorms
late Sunday afternoon into Sunday night. CAMs depict a line of
showers and thunderstorms moving through from the north. Model
solutions vary from completely weakening this line to some
maintaining the strength of this line as it moves southward.
Higher severe threat is within more western locations and these
locales get warmer during the day and lower severe threat is for
eastern locations that will have more stabilizing effect of the
marine layer.-- End Changed Discussion --
&&
.LONG TERM /MONDAY THROUGH SATURDAY/...
Overall not much change in the long term period.
High pressure returns for Monday and will continue through Tuesday
night with dry weather expected. Both days are expected to be
somewhat mild with highs in the 60s to lower 70s.
Unsettled conditions return mid and late week as a warm front slowly
approaches from the south on Wednesday. The warm front associated
with a low pressure in the middle of the country.
Expect shower chances to increase through the day as the front
either slowly approaches or stalls over the area. PWATS increase to
over an inch, however better forcing remains west of the region.
Expecting mainly light rain at this point. Area is then warm
sectored Thursday afternoon as a cold front approaches from the
west. Can not rule out a few rumbles of thunder with the frontal
boundary, however, confidence remains low and will not include
in the forecast at this time.
The chance for unsettled weather remains Friday into Saturday as
another quick moving frontal system may impact the area, with shower
chances remaining. There is some uncertainty with this second cold
front will limit POPs to just chance.
With the unsettled weather expected and mostly cloudy skies
forecast, highs Wednesday through Saturday will generally remain in
the 50s and 60s.
&&
.AVIATION /21Z SATURDAY THROUGH THURSDAY/...
High pressure builds toward the terminals today. Low pressure
approaches from the Great Lakes on Sunday.
VFR through the TAF period.
WSW to W winds of 15 to around 20 kt with gusts around 25-35 kt. As
a surface trough and showers associated with the trough (which
should have much, if any impact to flight categories) move through,
winds may gust higher than the prevailing forecast through around
22Z. A TEMPO group was added for gusts around 40 to 45 kt during
this time frame. Winds may also shift toward 290-300 true as this
surface trough moves through the terminals through 22Z. Winds begin
to taper after 00Z Sunday, with gusts completely gone between 06-
09Z. Winds shift to the S to SW Sunday morning, with gusts returning
by the late morning to early afternoon at 25 to 30 kt.
Low end VFR in stratocumulus cloud cover/ceilings continue for the
remainder of this afternoon with clouds diminishing this evening.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Gusts of 40 to 45 kt are possible through 22Z with the passage of a
surface trough and associated showers.
Ending time of gusts early Sunday may be +/- a few hours. Winds may
shift more toward 290-300 true with the passage of a surface trough.
OUTLOOK FOR 18Z SUNDAY THROUGH THURSDAY...
Sat night: VFR W-NW winds gust around 25kt.
Sunday: Mainly VFR. Chance of MVFR and showers in the afternoon.
SW-W winds G20-25kt.
Mon through Tue: Mainly VFR.
Wed and Thu: Slight chc of MVFR late Wed.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90
&&
.MARINE...
Gale warning now in effect for all waters. LI Sound and Bays
gale warning goes until 9PM and NY Harbor and ocean gale warning
goes until 10PM. Thereafter, expecting much of the remainder of
the night to have SCA level winds especially on the ocean. Ocean
seas retain SCA levels through tonight.
On Sunday, non-ocean will have sub-SCA conditions in the morning
with increasing chances for SCA level gusts in the afternoon,
especially for the LI South Shore Bays. The ocean likely remains
at SCA levels for Sunday on average. SCA level gusts will be
likely for most waters Sunday evening. Overnight, wind gusts
drop to below SCA levels but ocean probably will still have
some gusts near 25 kt. Ocean seas likely remain at SCA levels
Sunday night.
SCA seas will continue on the ocean waters into Monday, with sub-SCA
conditions then expected on all waters Monday night through
Wednesday. Sub small craft conditions are likely on all waters
through midweek.
&&
.HYDROLOGY...
Any showers tonight will result in less than a tenth of an inch
of rainfall.
With a fast speed expected with the showers and thunderstorms
Sunday afternoon into Sunday night, no hydrologic concerns are
expected with rainfall amounts forecast of less than a half
inch.
No hydrologic concerns exist thereafter throughout the rest of
the forecast period.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Gale Warning until 9 PM EDT this evening for ANZ331-332-335-
340-345.
Gale Warning until 10 PM EDT this evening for ANZ338-350-353-
355.
&&
$$
SYNOPSIS...JM
NEAR TERM...JM
SHORT TERM...JM
LONG TERM...BC
AVIATION...JP
MARINE...BC/JM
HYDROLOGY...BC/JM