594
FXUS61 KOKX 051121
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
721 AM EDT Thu Sep 5 2024
.SYNOPSIS...
High pressure remains northeast of the area today then drifts
east tonight through Friday. A cold front will move through the
area Saturday afternoon into the evening. High pressure builds
in thereafter and will stay in control through at least the
middle of next week.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Update is for current conditions.
High pressure northeast of the region, and nosing down into the
mid Atlantic region, remains in control today. Meanwhile, an
offshore low east of the Carolina coast will deepen and begin to
track to the north northeast. Some high cloudiness may move into
the southern portion of the region through today. An easterly
flow will keep temperatures similar to Wednesday`s, and slightly
below seasonal normals.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY NIGHT/...
An upper trough digs into the Great Lakes and upper midwest
tonight through Friday night as surface high pressure drifts
east and weakens its influence across the region. Meanwhile the
offshore low continues to move to the north northeast and
passes well to the east Friday night. There may be some high
clouds with the low tonight, and then drier air moves in aloft.
The lower levels do moisten somewhat tonight with stratus
possible. With weak lift and little moisture have removed the
chance of precipitation. If anything does occur along the coast
will be just a few sprinkles. Otherwise, dry weather continues
through Friday night. A few showers may approach the far
northwest regions late Friday night with the approach of a cold
front.
&&
.LONG TERM /SATURDAY THROUGH WEDNESDAY/...
The latest guidance is in agreement on an upper level low being
located over the Great Lakes by Saturday morning, with the
associated surface low being just east, over southwest Quebec. A
cold front extending south from the surface low will be approaching
the area. At the same time, an offshore low will be passing well to
the east. There may be some left over surface ridging nosing in from
the northeast. This will depend on exact strength and or track of
the offshore low.
Showers and thunderstorms are expected ahead of and along the cold
front, mainly Saturday afternoon through the evening. This timing
has sped up compared to 24 hours ago. Showers could start as early
as Saturday morning depending on aforementioned surface ridging from
the north. The latest Canadian shows a stronger and larger offshore
low and in turn shows the surface ridge breaking down earlier. This
is likely leading to the Canadian showing the earliest QPF.
Ahead of the cold front, guidance continues to show only weak
instability with MUCAPE values maxing out around 500-750 J/kg. Will
continue to keep thunderstorm probs at slight chance, but with pwat
values expected to be between 1.50 and 1.75 inches, anything that
does get going could produce moderate to locally heavy rain. See
Hydrology section below. Much of the area will likely be dry after
midnight, with some lingering shower chances for far eastern
locations into Sunday morning.
High pressure builds in thereafter and will bring another dry
airmass to the region. An upper level trough remains over the
northeast through Monday night with the flow becoming more zonal
after that. This pattern will lead to dry conditions and plenty of
sun through at least midweek. There could be a few weak cold
frontal/surface trough passages early in the week, but this will
likely not result in any PoPs.
&&
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
-- Changed Discussion --
High pressure retreats to the northeast, remaining in control
through much of the TAF period. Low pressure passes well
offshore on Friday
VFR through the first half of tonight. MVFR cigs expected to move
into the area after 06z Friday.
Winds will back E-NE this morning. SE sea breezes either side
of 10 kt expected this afternoon, except at KLGA and KBDR, which
should hang onto an ENE and E wind respectively off Long Island
Sound until mid to late afternoon. The winds will then lighten
again by this evening and back more to the NE.
Some sprinkles or drizzle can not be ruled out after 06z Friday.
Confidence is low and any activity will likely be light enough
to not cause vsby restrictions.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Timing of wind shifts could be off an hour or two.
Potential for MVFR cigs to start later than the TAF shows Friday
morning.
OUTLOOK FOR 12Z FRIDAY THROUGH MONDAY...
Friday: MVFR to start with NE winds. Becoming VFR in the
afternoon.
Friday night: Potential for MVFR.
Saturday: MVFR cigs possible in the afternoon. Showers with MVFR or
lower cond also possible mainly late day and at night. SE-S winds
G20kt possible in the afternoon.
Sunday and Monday: VFR.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
High pressure over the region will result in a weak pressure
gradient, keeping winds and gusts below advisory levels today
through Friday night. However, with an increasing SE swell from
offshore low pressure passing east of the waters Friday night
will build ocean seas to near 5 feet by late this afternoon, and
keep seas elevated through at least Friday night. At this time
a SCA for the ocean waters going into effect this afternoon was
extended through Friday, and will likely need to be extended
into Friday night. Seas across the ocean zones look to remain
at 5-6 ft through early Sunday morning. With high pressure
building in thereafter, winds and waves will remain below SCA
criteria.
&&
.HYDROLOGY...
No significant hydrologic issues are expected through the middle of
next week. Some moderate to potentially heavy showers/thunderstorms
are possible Saturday afternoon into Saturday evening, mainly north
and west of NYC. This activity could cause some minor and poor
drainage flooding, but the chances are low. The WPC has kept the
marginal risk of excessive rainfall where it has been the past two
days, north and west of NYC.
&&
.TIDES/COASTAL FLOODING...
A high risk for rip currents remains today and was extended into
Friday evening with building onshore SE swells and increasing
easterly winds.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...High Risk for Rip Currents through Friday evening for NYZ075-080-
081-178-179.
NJ...None.
MARINE...Small Craft Advisory from 2 PM this afternoon to 6 PM EDT
Friday for ANZ350-353-355.
&&
$$
SYNOPSIS...MET/JT
NEAR TERM...MET
SHORT TERM...MET
LONG TERM...JT
AVIATION...JT
MARINE...MET/JT
HYDROLOGY...MET/JT
TIDES/COASTAL FLOODING...