Area Forecast Discussion Issued by NWS Upton, NY
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000
FXUS61 KOKX 290010
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
810 PM EDT Sun May 28 2023
.SYNOPSIS...
High pressure remains into tonight, weakening late. A backdoor
cold front moves through Memorial Day. High pressure then
dominates through the upcoming week, with weakening southern low
pressure tracking south of the region. A cold front approaches
Friday and passes though late in the day or at night. Canadian
high pressure builds back into the region for next weekend.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
The forecast is mainly on track with minor adjustments made to
some of the hourly weather elements based on the latest trends.
The upper Omega block will remain in place through tonight while
surface high pressure gradually weakens. The high will keep
higher clouds associated with low pressure along the
southeastern coast suppressed, moving into the southern areas.
As the high weakens late a backdoor cold front will begin to
approach.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH TUESDAY/...
The upper ridge will remains over the northeast and mid Atlantic
into Tuesday as the upper low along the southeastern coast
slowly weakens. Meanwhile the timing of the backdoor cold front
is a little quicker, moving into the eastern areas mid morning
Monday, and move across the region into the afternoon, as east
flow develops, bringing in a cooler airmass. By evening the
front will be moving into eastern Pennsylvania. High pressure
then returns Monday night into Tuesday. Only a few high clouds
will accompany the frontal passage as there is little moisture
through the atmosphere column.
The low along the southeastern coast moves inland and weakens
Monday, and then drifts east under weak steering flow.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
Surface high pressure ridge will stretch across the area to
start the long term, and models continue to show low pressure
meandering off the Mid Atlantic Coast as it weakens. Most of the
guidance continues to keep rain out of the forecast area with
the northern periphery maybe brushing the offshore waters at
times Tuesday night through Wednesday. Will continue with a dry
forecast for this period over land, with highs on Wednesday
generally in the 70s.
High pressure remains in place for Thursday with temperatures
warming through the boundary layer. Models are now averaging around
15C at 850mb, which has trended cooler over the past couple of days,
and mixing might not be as deep as 850mb with a easterly flow,
although it will be a light flow. Thought deterministic NBM could be
too cool, so blended in the warmer 50th percentile.
Still some uncertainty regarding when a cold front will be passing
through during the Friday/Friday night time frame, but the timing
has trended slower over the past couple of days. Have gone with a
slight chance of a shower/thunderstorm north of the city in the
afternoon, then as slight chance everywhere at night. A prefrontal
trough may promote an offshore flow for some coastal areas, and with
850mb temps progged at 16-18C, have gone close to the 50th
percentile NBM, which was warmer than deterministic.
Cooler for the weekend with high pressure building in from the north
or northeast behind the cold front. A cyclonic flow aloft will bring
a slight chance of an afternoon shower NW of the city Saturday
afternoon, otherwise dry through the weekend. NBM looked too warm
for high temperatures considering an onshore flow and progged temps
at the top of the mixed layer, so used the 25th percentile. Similar
temperatures are expected for Sunday - mostly in the 70s.
&&
.AVIATION /00Z MONDAY THROUGH FRIDAY/...
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Gradually weakening high pressure across the area will give way
to an approaching cold front from the north early Monday. High
pressure from the north returns thereafter.
VFR conditions are expected through the TAF period. Light
southerly winds tonight will become nearly calm and variable
direction overnight.
Winds will transition to more easterly flow on Monday and
become gusty going into Monday afternoon. Wind speeds generally
below 10 kt tonight into Monday morning, and near 10-15 kt
Monday afternoon with gusts near 20 kt. However, east of NYC
terminals Monday afternoon, winds are forecast to be more near
15 kt with gusts around 25 kt.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Timing of gusts on Monday could be 1-3 hours off with start and end
times. Gusts could occasionally be a few kts higher than in TAF.
OUTLOOK FOR 00Z TUESDAY THROUGH FRIDAY...
Monday night: VFR. Easterly winds near 10-15 kt with gusts near 20
kt for evening, diminishing overnight.
Tuesday through Thursday: VFR.
Friday: Mainly VFR. Possible showers/thunderstorms and MVFR,
mainly at night.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
Cold water headlines continue through tonight.
High pressure over the waters weakens late tonight as a backdoor
cold front approaches. Winds and seas will remain below advisory
levels across all the waters. The backdoor cold front moves
across the water Monday morning into Monday afternoon. High
pressure then builds in behind the front. Winds will be
increasing behind the front with gusts approaching 25 kt on the
ocean waters, south shore bays, and New York harbor in the
morning and into the afternoon, east to west. A SCA has been
issued for these waters. Ocean seas may still be at 5 feet into
Tuesday morning on the eastern ocean and into the afternoon on
the western ocean waters, and the advisory may need to be
extended.
On the eastern bays and the far eastern Long Island Sound gusts
will be just under 25 kt and will mention occasional gusts to
25 kt. However, if later forecasts indicate higher wind gust
potential an advisory may be issued for these waters.
And on the central and western Long Island Sound gusts are
expected to remain below 25 kt.
With high pressure over the waters once advisory conditions end
sub SCA conditions will continue through the end of the week.
Persistent SE swells gradually subside middle to late week.
&&
.HYDROLOGY...
No hydrologic impacts are expected through the entire forecast
period.
&&
.TIDES/COASTAL FLOODING...
A moderate risk of rip current development at Atlantic Ocean
beaches continues through Tuesday.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory from noon to 8 PM EDT Monday for ANZ338-
345.
Small Craft Advisory from 10 AM Monday to 6 AM EDT Tuesday for
ANZ350.
Small Craft Advisory from noon Monday to 6 AM EDT Tuesday for
ANZ353-355.
&&
$$
SYNOPSIS...JC/MET
NEAR TERM...MET
SHORT TERM...MET
LONG TERM...JC
AVIATION...JM
MARINE...JC/MET
HYDROLOGY...JC/MET
TIDES/COASTAL FLOODING...