Area Forecast Discussion
Issued by NWS Upton, NY

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981
FXUS61 KOKX 091128
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
728 AM EDT Thu May 9 2024

.SYNOPSIS...
Multiple low pressure systems form southwest of the area today and
track nearby to the south tonight through Friday night. A series
of lows move through the vicinity of the region this weekend.
High pressure builds offshore for early next week before another
low potentially moves in for the middle of next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
For this update adjusted cloud cover to better match satellite,
along with temperature and dew points through late morning to
better match the latest observational trends.

The area will have the northern edge of high clouds streaking across
this morning, before mid level clouds arrive during this afternoon.
The pressure gradient in the wake of the cold front pressing
further south slackens off by mid to late morning, thus the
winds will be light throughout the day and generally around 5
mph or so. Multiple low pressure centers from across the Ohio
Valley during the first half of today, before getting into the
Central Appalachians later today and this evening. This will
bring more in the way of clouds towards late this afternoon and
this evening. Have pushed back the timing of the higher coverage
/ percentage of rain / showers for today. A good percentage of
the day will be completely dry. This will change however towards
the late day and evening. Temperatures will be close to normal
with mainly upper 60s to lower 70s.

During this evening the column will gradually moisten. Showers
should break out for all areas at some point during the evening. The
low level flow will start to become onshore and out of the ENE. This
should lead to a stratiform rain / shower activity, although there
is some hint of a small amount of CAPE / instability in BUFKIT
soundings. Much of the time the rain will be light, with perhaps a
couple of moderate pulses into Friday morning. Temperatures should
average closer to normal with lows in the upper 40s to lower
50s.

&&

.SHORT TERM /FRIDAY THROUGH FRIDAY NIGHT/...
For Friday expect overcast skies with periods of light rain
continuing. The CAMs are in fairly good agreement on it being a damp
and unsettled day. There are differences among the various guidance
as to whether some steadier rain could develop for the afternoon as
suggested by some HRRR model runs. The winds will remain onshore out
of the ENE and this will keep temperatures below average with a wind
off the colder water and overcast skies. Temperatures therefore in
all likelihood will have difficulty getting out of the 50s.

For Friday night the last wave of low pressure gets a bit further to
the south and eventually offshore. This should lead to more of a NE
to N flow which should result in a little bit of low level drying.
Thus the guidance is indicating light rain or showers becoming more
intermittent and even ending before daybreak Saturday. Total
rainfall amounts will total up to a half inch or so for much of
the area, with lesser amounts further northeast. NW sections of
Orange County may receive up to 3/4 of an inch. Temperatures
should be near normal with middle 40s to around 50 for lows.

&&

.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
The upper level jet is shown to remain south of the region this
weekend and then with more ridging next week, parts of the upper
level jet traverse the local area.

Mid level trough south of region Saturday morning, then shifts east
during the day with brief ridging as the local area will be in
between shortwaves.

Next shortwave moves in Saturday night with another moving south of
the region Sunday. The larger trough encompassing these shortwaves
and periodic positive vort maxima will be lingering across the
region through Sunday. This trough then moves east of the region
Sunday night.

Overall, the larger scales convey a mid level ridging trend taking
place for early into middle of next week for the local area. For
Monday night into early Tuesday next week, a subtle small shortwave
embedded within the ridge is forecast to move across. Wednesday into
Wednesday night, the next trough could be potentially moving in from
the west, although the timing with the guidance varies with some not
bringing in the trough until Thursday

At the surface, low pressure moves south and eventually southeast of
the region Saturday. Weak pressure gradient follows across the local
region. This weak high pressure will be brief as low pressure
approaches Saturday night and moves near to south of the area early
Sunday. Low pressure passes southeast of the region Sunday into
Sunday night.

Offshore high pressure briefly builds in late Sunday night into
early Monday and then moves farther offshore as another wave of low
pressure approaches Monday afternoon into Monday night. This low
pressure will be weak and will traverse the local area late Monday
night into early Tuesday. Another low may approach the area next
Wednesday.

Chances of rain showers are forecast much of this weekend. Despite
cooler air aloft, cooler air will also be in place at the surface,
so there may not be as much instability on Sunday as previously
thought. Have removed chances for thunderstorms in favor of showers
on Sunday.

Mainly dry conditions are forecast Sunday night through Monday.
Then, the next chance of rain showers is forecast Monday night and
again Tuesday afternoon into the midweek timeframe, depending on how
and when the trough sets up and traverses the region.

Temperatures for the weekend exhibit less of a diurnal trend, and
generally expected to be below normal for daytime hours and then
near to above normal for next week.

&&

.AVIATION /12Z THURSDAY THROUGH MONDAY/...
A cold front that passed through overnight will stall to our
south near the mid-Atlantic region. A wave of low pressure
tracks along the stalled boundary to our south late today
into tomorrow.

VFR today. Then in the evening, toward 00Z, there is a chance
of showers, with MVFR occurring a few hours after the rain`s
arrival, then possibly dropping to IFR a few hours after that,
particularly for west and south terminals. It remains this way
through the early afternoon on Friday.

Winds are currently NW around 10 kts to 15 kts with some
occasional gusts. Winds turn almost due north a few hours after
daybreak 5-10kts with gusts diminishing. Winds shift in the
afternoon becoming southeasterly with the sea breeze around
18-21Z with gusts up to 20kt possible in the evening and night.
Amendments may be needed for sea breeze timing.


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

A sea breeze in the afternoon may require amendments to adjust
for timing.

Timing of the rain`s arrival and lowering of ceilings this
evening may be off by a couple of hours.

OUTLOOK FOR 12Z FRIDAY THROUGH MONDAY...

Friday: MVFR or lower with showers likely. SE G20kt.

Saturday and Sunday: Chance of MVFR or lower in showers.

Monday: Mainly VFR. Isolated showers possible at KSWF.

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

&&

.MARINE...
A weak pressure gradient will lead to light winds for much of today,
before a E to ENE wind gets established tonight. Sub small craft
conditions will prevail through today with 2 ft ocean seas. By
tonight the ENE flow should increase enough on the north side of a
front down to the south. Small craft wind gusts develop on the ocean
and NY Harbor with more marginal small craft gusts which may be more
occasional for the remaining non-ocean waters for tonight. By Friday
the winds should very slowly decrease as the winds gradually back
more to the NE and N into Friday night. Thus, prevailing sub small
craft conditions likely to resume by late Friday afternoon. For the
long term period of Saturday through Monday night, SCA conditions
are unlikely for winds with waves on the ocean remaining around 3
feet, occasionally 4 feet.

&&

.HYDROLOGY...
There are no hydrologic concerns throughout the forecast period.

&&

.TIDES/COASTAL FLOODING...
Astronomical tides continue to run high from the new moon earlier
this week.

Another round of mainly minor coastal flooding, with localized
moderate flooding is possible for the more vulnerable spots of
southern Nassau, with advisories spread along the northwestern and
much of the southwestern LI Sound coastal zones. Advisories are also
in effect for Thursday evening / night for Southern Queens, Southern
Brooklyn, Staten Island, and Hudson in NE NJ. Statements for tonight
have also been issued for SW and SE Suffolk as some spots may touch
minor benchmarks.  Another and perhaps final round of mainly minor
coastal flooding is likely for Friday night.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...Coastal Flood Advisory from 11 PM this evening to 3 AM EDT
     Friday for CTZ009.
NY...Coastal Flood Advisory from 11 PM this evening to 3 AM EDT
     Friday for NYZ071-078.
     Coastal Flood Advisory from 8 PM this evening to midnight EDT
     tonight for NYZ074-075-178-179.
     Coastal Flood Advisory from midnight tonight to 4 AM EDT
     Friday for NYZ176-177.
NJ...Coastal Flood Advisory from 8 PM this evening to midnight EDT
     tonight for NJZ006.
MARINE...Small Craft Advisory from midnight tonight to 2 PM EDT Friday
     for ANZ338-350-353-355.

&&

$$

SYNOPSIS...JE/BR
NEAR TERM...JE
SHORT TERM...JE
LONG TERM...BR
AVIATION...BR
MARINE...JE/BR
HYDROLOGY...JE/BR
TIDES/COASTAL FLOODING...