908
FXUS61 KOKX 200545
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
145 AM EDT Tue Aug 20 2024
.SYNOPSIS...
A cold front continues moving offshore overnight. High pressure
then slowly builds in from the Great Lakes later today into tonight.
Weak low pressure moves by just to the north across New England
on Wednesday. High pressure moves in Wednesday night from the
Great Lakes and remains the predominate feature through Saturday
night. High pressure may lose hold as weak low pressure passes
to our north Sunday into Monday.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
The cold front has pushed into far eastern portions of the area
and will continue moving offshore through the rest of the
overnight and early morning. While the threat for locally heavy
downpours has ended with drier air beginning to push in at the
lower levels, there may still be a pop up shower to two for a
few more hours with strengthening winds in the upper levels
with a jet streak. No sensible weather impacts are anticipated.
Drier air works its way steadily into the region overnight from
west to east. Otherwise, lows overnight are expected to be
mainly in the upper 50s to middle 60s. Dew points will be
falling into the 50s from west to east, with some 50s further
east towards day break.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 AM WEDNESDAY/...
Tuesday will feature slow moving and weakening low pressure
within the Canadian Maritimes that will keep the cold front from
moving too far offshore. Further weakening of this low is
expected Tuesday night.
Relatively cooler temperatures are forecast Tuesday and Tuesday
night. Forecast highs mainly in the 70s and forecast lows
mainly in the upper 40s to around 60. The forecast highs are
around 5 degrees below normal and the forecast lows are around 5
to 10 degrees below normal.
A westerly flow will be maintained across the region but is not
expected to be too gusty. Much drier air is expected as
dewpoints lower into upper 40s to mid 50s across much of the
region. Dry weather expected for Tuesday through Tuesday night.
Used consensus of MOS and NBM for temperatures.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
Cooler and drier air remains in place on Wednesday with a trough and
strong cold air advection aloft. 850mb temps will be 7-10C below
average at around 6-4C with a northwesterly flow at the surface.
This will make it feel like a false start to fall with highs on
Wednesday in the mid-70s to upper-60s followed by Wednesday night
lows in the 50s.
Showers and thunderstorms are also possible Wednesday afternoon and
evening. There are several factors working both for and against the
chance for rain on Wednesday. We`ve got a weak surface low in New
England with a surface trough expecting to extend across the area
that may provide a source of lift for shower and thunderstorm
development. We`ve also got vorticity advection along the
500mb low/trough in New England aiding in development of rain.
However, cold air aloft, cooler surface temps, weak instability, and
PWATs at or below 1 inch will work against the showers and
thunderstorms. Expecting mainly isolated coverage with possible
scattered coverage for far northern zones closer to the low.
Surface high pressure builds into the region from the Great Lakes
Wednesday night and remains in place through Saturday. This will
lead to an extended period of dry weather. A trough exits to the
east on Thursday as a ridge takes over. This will lead to gradually
warming temperatures. NW flow continues on THursday under high
pressure which will keep temperatures on the cool side with highs in
the upper to low-70s. Upper-70-s to lower-80s return on Friday as
ridging builds aloft and surface winds become more westerly,
eventually southwesterly by the afternoon. Westerly to southerly
flow continues into the weekend allowing for further warming with
highs in the low/mid-80s.
Global models are not in a consensus Sunday in to Monday. The GFS
has a trough develop over the area, GDPS/ECMWF have the trough
farther displaced from our area to the northeast, ICON does not have
a trough develop and keeps us under a ridge. Only the GFS solution
would bring a chance for rain. Given the divergence in model
guidance, have kept POPs out of of the ending periods in the
extended forecast.
&&
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
-- Changed Discussion --
High pressure slowly builds into the region today and tonight.
Mainly VFR. There is a chance for an isolated light shower or
sprinkle overnight. There may also be brief periods of MVFR
ceilings around 2.5-3kft.
Winds will remain NW through the TAF period. Wind speeds around
10 kt overnight. Winds then increase after day break, becoming
10-15kt with gusts around 20 kt. The gusts could end up
occasional and any gusts likely end in the evening.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Can not rule out an occasional gust early this morning.
MVFR ceilings around 030 possible overnight.
Gusts may be occasional today.
OUTLOOK FOR 06Z WEDNESDAY THROUGH SATURDAY...
Tuesday Night: A gust G15-20kt possible in the evening. VFR.
Wednesday-Saturday: VFR.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
SCA conditions are expected to remain across the ocean mainly
due to seas through Tuesday. Otherwise, conditions will be
below SCA through the late week and upcoming weekend with high
pressure building into the region.
&&
.HYDROLOGY...
No additional hydro concerns tonight with mainly dry conditions
to follow Tuesday through the upcoming weekend.
&&
.TIDES/COASTAL FLOODING...
A high rip current risk is in place through Tuesday due to
elevated, long period swells from Ernesto.
Ocean seas are forecast to be highest through Monday, and with
surf heights up to 6 ft, local beach erosion is possible.
A full moon today as well as swell from distant Ernesto will
also elevate total water levels this week.
Additional minor flooding is possible with the high tide cycles
(especially the evening/nighttime cycles) through much of this
week. Additional advisories/statements will likely be needed.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...High Risk for Rip Currents through this evening for NYZ075-080-081-
178-179.
NJ...None.
MARINE...Small Craft Advisory until 6 PM EDT this evening for ANZ350-
353-355.
&&
$$
SYNOPSIS...JM/BR
NEAR TERM...JE/JM
SHORT TERM...JM
LONG TERM...BR
AVIATION...BC
MARINE...JM/BR
HYDROLOGY...JM/BR
TIDES/COASTAL FLOODING...