141
FXUS61 KOKX 111805
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
205 PM EDT Sat May 11 2024
.SYNOPSIS...
-- Changed Discussion --
High pressure builds in from New England this afternoon, then a
frontal system tracks through tonight into Sunday. High pressure
briefly returns Sunday night. High pressure then moves
offshore early next week followed by a low pressure area moving
across midweek. Weak high pressure returns thereafter towards
the end of next week.-- End Changed Discussion --
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Forecast on track this afternoon. A weak high ridges down from
New England this afternoon with a mid level ridge overhead.
These features are all within a larger mean upper level trough
over eastern North America. Clouds will vary in coverage to this
afternoon with at least partly sunny skies for most areas.
Middle and high clouds should begin to increase late.
Highs will be in the upper 50s to lower 60s, warmest away from
the immediate coast, 5-10 degrees below average for this time of
year. ESE flow is already developing which will likely cap off
any temperature rise near the coast for the remainder of the
afternoon.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/...
With troughing increasing from the west with an approaching frontal
system in the Great Lakes, cloud cover is expected to increase
Saturday evening into Saturday night. PWATs of 1"+ will also be
advected in from the west with positive vorticity advection and warm
air advection aloft both occurring, aiding in the formation of clouds
and eventual rain.
The trough will guide a weakening frontal system into our area
overnight Saturday with an occluded front. Rainfall will start in
the west overnight and spread eastward toward daybreak and into the
morning. Given the weakening nature of the system, most of the
rainfall will likely occur over far western sections of the area
with much lighter precip expected for the rest of the CWA due to
weaker forcing. Some may only pick up a trace or even remain dry (in
eastern areas), while those in far western sections of our CWA could
see around a quarter inch.
No thunderstorms are expected due to a stable environment.
Temperatures will be cooler on Sunday from the influence of the
trough, cloud cover and rain. Highs are expected to be in the mid-
50s, around 10-15 degrees below seasonal norms.
Expecting slow improvement Sunday afternoon and evening as high
pressure returns once again with weak ridging aloft increasing from
the west. Given the weak high taking over and the weak departing
low, the pressure gradient will be weak, meaning mostly light winds
Sunday night. And with the high pressure clearing clouds, could
expect some weak radiational cooling. Lows are forecast to be in the
mid/upper-40s with the LI Pine Barrens and interior areas in the low-
40s.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
In the mid levels, ridging early next week will be followed by a
trough moving in for midweek. Model differences with timing and
evolution of trough with ECMWF showing a cutoff low. ECMWF keeps a
slower movement of the cutoff low while the GFS and Canadian models
depict a faster more progressive trough shifting more east of the
area towards the end of next week.
At the surface, high pressure based in the Atlantic will allow for
more southerly flow to develop early next week. Low level warm air
advection is forecast with a warming trend to daytime temperatures
from Monday to Tuesday. More easterly component of flow develops for
midweek as low pressure approaches from the west. Like the
mid levels, differences become more apparent in model solutions
regarding the speed, location and strength of the low. ECMWF
lingers the low nearby for Thursday and Thursday night while the
GFS and Canadian models show the low moving farther east of the
region. Weak high pressure follows for Thursday into Friday.
Next substantial rain event depicted in the general Tuesday to
Wednesday night timeframe. Tuesday night and Wednesday could present
some embedded thunderstorms, with a slight chance with elevated
instability and colder air aloft moving in.
Temperatures mainly near to above normal during the long term.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
-- Changed Discussion --
Weak high pressure building in from New England this afternoon
will give way to an approaching weak frontal system tonight
into early Sunday.
BKN VFR cigs inland should expand toward the NYC metros and KISP
late today into this evening. VFR expected much of tonight, then
light showers with MVFR cond should arrive at KSWF after 08Z, to
KHPN and the NYC metro 09Z-10Z, and KBDR/KISP by 12Z. Can`t rule
out brief IFR cigs at KSWF during mid to late morning. KGON
should remain VFR.
SE-S flow either side of 10 kt (with the higher speeds closer to
the coast) should diminish to under 10 kt tonight, and may go
light/vrb at outlying terminals. SE flow under 10 kt expected
daytime Sunday.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
No unscheduled AMD expected.
OUTLOOK FOR 12Z SUNDAY THROUGH WEDNESDAY...
Late Sunday afternoon and Sunday night: VFR.
Monday: Mainly VFR.
Tuesday: MVFR or lower possible in mainly afternoon showers.
S winds 15kt coastal terminals.
Tuesday night: MVFR likely in showers and possible tstms.
S winds 10-15kt coastal terminals.
Wednesday: MVFR or lower still likely in showers and t-storms.
SE winds 10-15G20kt, becoming NE.
Wednesday night: VFR. N winds 10-15G20kt.
Thursday: VFR.
Detailed information, including hourly TAF wind component
forecasts, can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
-- Changed Discussion --
Winds and seas should remain below SCA levels this weekend.
Mainly below SCA conditions forecast Monday through Tuesday
with more probable SCA conditions for mid week.-- End Changed Discussion --
&&
.HYDROLOGY...
No significant hydrologic problems anticipated.
&&
.TIDES/COASTAL FLOODING...
Many locations are expected to fall short of minor coastal flood
benchmarks for high tide cycles tonight. However, the South
Shore Bays of Nassau County NY could have some locations that
touch or slightly exceed their minor coastal flood benchmarks.
A coastal flood statement has been issued for Southern Nassau
County between 9PM EDT this evening and 1AM Sunday EDT overnight.
No additional coastal flooding is anticipated Sunday into next
week as astronomical tide levels continue to subside.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...None.
&&
$$
SYNOPSIS...JM/BR
NEAR TERM...BR/DS
SHORT TERM...BR
LONG TERM...JM
AVIATION...BG
MARINE...JM/BR
HYDROLOGY...JM/BR
TIDES/COASTAL FLOODING...