613
FXUS61 KOKX 121755
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
1255 PM EST Tue Nov 12 2024
.SYNOPSIS...
Strong high pressure builds in through tonight. High pressure
slowly moves farther northward away from the region Wednesday
into Wednesday night. A weakening frontal system will approach
from the west on Thursday while an ocean storm passes well to
the east and moves into the Canadian Maritimes. This storm will
then remain over the Canadian Maritimes into Monday as another
high builds into the region Sunday into early next week.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Northern stream shortwave slides offshore today, with high
pressure building into the eastern Great Lakes today.
This will continue subsidence with mostly sunny sky conditions,
low rh values and very gusty NW flow thru this afternoon. Fire
weather primary of concern today with a red flag warning in
effect for all forecast zones. See fire weather section for more
details.
Used a blend of MAV and MET mos for high temperatures which will
be much cooler than the previous day, staying in the 50s.
&&
.SHORT TERM /6 PM THIS EVENING THROUGH THURSDAY/...
A consistent mid level ridging trend continues tonight through
early Thursday. At that point, mid level ridge axis will be
overhead and weakening. A cutoff mid level low approaches from
the west with lowering heights across the local area.
High pressure will continue building into the region tonight.
Steep enough of a pressure gradient to keep gusty winds but
magnitude will be decreasing after the first few hours of this
evening.
Dry conditions continue but the winds will help mitigate
radiational cooling with mostly clear sky conditions.
Forecast lows a blend of MAV and MET, ranging from mid 20s to
upper 30s.
For Wednesday through Wednesday night, the high pressure will
slowly move farther northward away from the local region. Dry
conditions will continue. Ridging aloft with a weakening of the
surface pressure gradient will allow for winds to decrease and
gusty to lower.
Colder airmass will continue to encompass the region with high
temperatures forecast to only reach upper 40s to near 50. For
Wednesday night with nearly clear sky conditions continuing plus
diminishing winds, efficient radiational cooling is expected.
More vast range of lows are forecast from upper teens to upper
30s. Outside of NYC, frost can be expected. However, within the
NYC Metro and where there is still active growing season,
surface will be too dry for frost to form despite temperatures
in the 30s.
For Thursday, clouds increase as a weakening frontal system
approaches. Conditions are forecast to remain dry with most
vertical forcing expected to be well south of the region.
Forecast highs will be relatively similar to the previous day.
&&
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
Mainly dry weather continues through much of the extended
period with only slight chances of precipitation across portions
of the region Thursday night through Friday morning.
Precipitation across western portions of the region during this
time frame will be associated with a weakening frontal system,
and little to no precipitation may fall, as forcing is weak, and
weakens as the system passes to the southwest. Low end chance
is possible across the south fork of Long Island Friday night as
an offshore low retrogrades into the Canadian Maritime under a
weakening Omega block, pushing some moisture toward the forecast
areas.
Temperatures below normal Thursday, slightly above normal for Friday
and Saturday, and 5 or more degrees above normal Sunday into the
beginning of next week.
With the NBM handling the weather rather well, with little deviation
from the deterministic, and with most parameters similar to the
previous forecast, have mainly followed the NBM. Only deviation was
for winds and gusts during the northwest and north flow regimes
Saturday and Monday as high pressure builds into the region.
&&
.AVIATION /18Z TUESDAY THROUGH SUNDAY/...
-- Changed Discussion --
High pressure builds in from the Great Lakes region with its
center passing north into Wednesday morning.
VFR through the TAF period.
N-NW winds of 15 to lower 20s kt with gusts to around 35 kt.
Some isolated gusts of 35 to 40 kt are possible. The gusts are
expected to remain into Tuesday evening, ending late tonight.
NY Metro (KEWR/KLGA/KJFK/KTEB)TAF Uncertainty...
Isolated gusts to 35 to 40 kt are possible into the early
afternoon.
OUTLOOK FOR 18Z WEDNESDAY THROUGH SUNDAY...
18Z Wednesday-Thursday: VFR. Slight chance of a shower Thursday
Night near the coast.
Friday-Saturday: VFR. NW wind gusts 15-20 kt possible Friday and NW
wind gusts 20-25 kt possible Saturday.
Sunday...VFR.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
SCA in effect for all forecast waters through tonight. Then on
Wednesday, a gradual decrease of winds is expected from NW to
SE. First waters to drop below SCA will be NY Harbor and
Western LI Sound (by 6AM Wednesday). This will be followed by
the rest of the non- ocean zones dropping below SCA (by 9AM
Wednesday). Then the western ocean (Sandy Hook NJ to Fire Island
Inlet NY) drops below SCA by 12PM Wednesday and lastly the rest
of the ocean zones east of Fire Island Inlet dropping below SCA
(by 6PM Wednesday). There is potential for SCA conditions
lingering on the ocean east of Fire Island Inlet for Wednesday
night and Thursday with otherwise sub-SCA conditions for the
local waters.
For today into this evening, there will be occasional gales.
Timeframe for these will be this morning as well as late
afternoon into early evening. Both the temporal and spatial
coverage is not high enough to warrant inclusion of ocean in a
gale warning but trends will be monitored for any potential
upgrades of SCA to gale.
Winds and seas will be below advisory levels on the waters into
late Friday. Late Friday into Saturday there is the potential
for marginal SCA conditions on the eastern ocean waters as
northwest winds and gusts increase as offshore low pressure
passes to the east.
&&
.FIRE WEATHER...
Breezy and dry conditions today, with continued drought
conditions. Minimum RH of 25 to 30 percent with frequent wind
gusts of 30 to 40 mph will continue through this afternoon. Due
to these expected conditions and after coordination with
surrounding forecast offices with input from land managers, a
red flag warning continues for the entire local forecast region
including NE NJ, NYC, Lower Hudson Valley, Southern CT and Long
Island till 6PM this evening.
Northwest wind gusts will remain in the 25 to 35 mph range
through this evening, only gradually diminishing late tonight to
15 to 20 mph range. Relative humidity will naturally go up
tonight, to 50 to 60 percent range by daybreak Wednesday.
Wind gusts to 20 to 25 mph likely in the morning, then 15 to 20
mph Wednesday afternoon, with relative humidity values falling
into the 20 percent range. Another day for enhanced brush fire
spread potentially for Wednesday.
&&
.HYDROLOGY...
Moderate drought conditions continue per US Drought Monitor.
Stream flows are generally below the 25th percentile of normal
for this time of year. There are no hydrologic concerns through
early next week.
&&
.TIDES/COASTAL FLOODING...
With an upcoming full moon on November 15th, astronomical tidal
levels will be on a rising trend. Tidal epartures needed for
minor flooding will be lowering to as litle as a couple of
tenths to 1/2 ft by Friday/Saturday.
Developing offshore low pressures and high pressure over the NE
coast mid to late week will result in a persistent northerly
flow and resultant Ekman effects, as well as a period of backed
NE flow Wed/Thu adn 3-4 ft long period easterly swells. This
will bring an increasing chance for coastal flooding during the
late night/AM high tides Wed into this weekend.
Potential for minor coastal flooding with high tide cycles for
late Wed Night early Thursday AM, especially within the South
Shore Bays, lower NY Harbor and Western LI Sound shorelines.
This threat will likely increase into Saturday AM with tidal
piling and full moon, with potential for localized coastal
flooding increasing as well.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...Red Flag Warning until 6 PM EST this evening for CTZ005>012.
NY...Red Flag Warning until 6 PM EST this evening for NYZ211>213.
NJ...Red Flag Warning until 6 PM EST this evening for NJZ002-004-
006-103>108.
MARINE...Small Craft Advisory until 9 AM EST Wednesday for ANZ331-332-
340-345.
Small Craft Advisory until 6 AM EST Wednesday for ANZ335-338.
Small Craft Advisory until 6 PM EST Wednesday for ANZ350-353.
Small Craft Advisory until noon EST Wednesday for ANZ355.
&&
$$
SYNOPSIS...JM/JP
NEAR TERM...JM/NV
SHORT TERM...JM
LONG TERM...JP
AVIATION...IRD
MARINE...JM/NV
FIRE WEATHER...
HYDROLOGY...JM/JP
TIDES/COASTAL FLOODING...