000
FXUS61 KOKX 212134 CCA
AFDOKX
Area Forecast Discussion...CORRECTED
National Weather Service New York NY
534 PM EDT Thu Mar 21 2024
.SYNOPSIS...
High pressure builds in from the south and west through Friday.
Low pressure approaches from the south Friday night into
Saturday and moves across late Saturday afternoon into early
Saturday evening. This low pressure system then moves east of
the region for the remainder of Saturday night. High pressure
ridges down from the north Sunday into Monday and remains into
Tuesday. A frontal system approaches from the west Tuesday night
and moves slowly eastward through midweek.
&&
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
High pressure builds in from the south and west through tonight.
Mostly clear sky conditions are expected but winds will
gradually lower as a result of a weakening pressure gradient.
Radiational cooling will be effective but not totally maximized
with winds staying up within the boundary layer. Forecast lows
are in the upper teens to upper 20s.
&&
.SHORT TERM /6 AM FRIDAY MORNING THROUGH SATURDAY/...
Dry conditions are expected to continue with high pressure in
control Friday. Winds will be light and daytime mixing will be
limited. With increasing clouds in the afternoon, daytime high
temperatures are only forecast to be in the low to mid 40s which
will be below normal for this time of year.
Low pressure and an upper level trough approach Friday night. For
Friday night, cloud coverage will eventually become overcast
with rain showers starting overnight and into daybreak Saturday.
Low pressure continues to approach the region Saturday with an
increase in SE flow. The trough will continue to approach as
well aloft with an associated increase in precipitable water.
This will lead to a greater moisture potential with this
approaching system. Rain becomes steady, falling at moderate to
occasionally heavy intensities during the day. There is a flood
watch in effect for NE NJ, NYC, Rockland NY, Westchester NY for
4AM Saturday through 2AM Sunday.
Less of a diurnal temperature range expected Friday night into
Saturday. Used consensus of raw model data Friday night and
Saturday. Forecast actually has increasing temperatures late
Friday night into Saturday morning.
Depending on exact start time, there could be a brief mix of
rain and snow for some parts of the far interior but expect any
accumulations of snow to stay under an inch. This will be
primarily a rain event.
&&
.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
With the precipitation ending during Saturday night, leaned more
toward the global guidance which is a little quicker than the NBM.
Upper troughing, and the surface low will be moving into the western
Atlantic through Sunday night, and then track slowly east into early
next week. Meanwhile an upper ridge builds into the eastern coast
Monday and moves offshore Tuesday, as surface high pressure noses
into the coastal plain from the north. With high amplitude riding
moving through the western Atlantic an approaching low pressure
system Tuesday,moves slowly across Tuesday night into Thursday.
*Key Messages*
* Lingering rain into Saturday night, then dry Sunday through
Tuesday.
* Gusty northerly winds likely late Saturday night through Sunday.
Remaining gusty, especially east, Sunday night into Monday evening.
* Unsettled, wet weather returns Tuesday night into Thursday.
* Near normal temperatures expected Saturday night through
Wednesday with a slight warm up Wednesday night and Thursday.
&&
.AVIATION /20Z THURSDAY THROUGH TUESDAY/...
High pressure through Friday.
VFR.
NW winds and gusts 15-25kt with G30kt early this evening will be
diminishing after 00Z Friday. Winds becoming W around 10 kt Friday.
NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
No unscheduled amendments expected.
OUTLOOK FOR 18Z FRIDAY THROUGH TUESDAY...
18z Friday: VFR.
Friday night: MVFR or lower developing after midnight with rain near
the coast and rain perhaps some brief wet snow inland for KSWF.
Saturday: IFR and rain. Rain heavy at times into evening. SE wind
gusts 20-25kt during the day with LLWS possible city east, becoming
N all areas with gusts 30-35kt at night.
Sunday: VFR. A slight chance of rain. N-NE wind gusts around 25kt.
Monday: VFR. NE gusts 20-25kt.
Tuesday: VFR.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90
&&
.MARINE...
The pressure gradient remains tight between low pressure going
into the Canadian Maritimes and high pressure to the north and
west of the local waters. Gusty NW flow remains through this
afternoon and into much of this evening before more
substantially diminishing overnight. SCA for all forecast
waters continues until 11PM. Then, with some lingering gusts and
higher seas over the eastern parts of the forecast ocean
waters, SCA from Fire Island to Montauk continue until 6AM
Friday. After 11PM aside from these eastern ocean zones, sub-SCA
conditions are expected.
A relaxing pressure gradient due to high pressure building in
will allow for conditions to go below SCA criteria for most
waters late tonight and then for all waters Friday into Friday
night. Conditions on Saturday trend back up to SCA range for
wind gusts for most waters and seas on the ocean. Western LI
Sound and NY Harbor are below SCA criteria Saturday in current
forecast but may trend more into SCA with wind gusts on
subsequent forecasts.
Strong and gusty northerly winds will develop behind a departing low
pressure system Saturday night. Winds and gusts will be increasing
to SCA levels across all the waters, with gale gusts becoming likely
across all the waters by late Saturday night.
Gales on the non ocean waters will be ending Sunday morning, with
SCA conditions then continuing into Monday night. Meanwhile, gales
will be remaining on the western ocean waters into late day Sunday,
and the eastern waters into Monday night as offshore low pressure
remains nearby and slowly weakens. Once gale conditions end on the
western ocean SCA conditions will then remain into Monday night.
&&
.FIRE WEATHER...
Based on collaboration with Fire WX partners and surrounding
WFOs, there are special weather statements for the entire region
with elevated fire weather concerns today into early this
evening. Gusty winds around 25 to 30 mph are expected with Min
RH values of 25 to 30 percent. The airmass remains anomalously
dry as rainfall the last 24 hours was mostly under a tenth of an
inch, therefore not sufficiently wetting the ground.
&&
.HYDROLOGY...
-- Changed Discussion --
Dry until late Friday night into early Saturday morning when
rain begins entering the area. Rain steady, moderate to heavy
during the day Saturday. Rain tapers off Saturday night from
west to east. Total rainfall forecast near 2 to 3 inches with
locally higher amounts possible. There will be potential for
flooding for NE NJ, NYC, as well as Rockland and Westchester
counties in NY. This region contains rivers and streams that may
potentially flood especially if locally higher than 3 inch
rainfall amounts occur. Low lying, poor drainage and urban areas
will also be vulnerable spots prone to flooding. There is a flood
watch in effect from 4AM Saturday until 2AM Sunday for these
aforementioned areas.
Hydrologic issues prior to Saturday night, rain ending during
Saturday night with little west, couple of hundredths, to 1 to 1.25
inches east.
No hydrologic issues expected Sunday through the middle of next week.-- End Changed Discussion --
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...Flood Watch from late Friday night through late Saturday night
for NYZ069>075-176-178.
NJ...Flood Watch from late Friday night through late Saturday night
for NJZ002-004-006-103>108.
MARINE...Small Craft Advisory until 11 PM EDT this evening for ANZ331-
332-335-338-340-345-355.
Small Craft Advisory until 6 AM EDT Friday for ANZ350-353.
&&
$$
SYNOPSIS...JM/MET
NEAR TERM...JM
SHORT TERM...JM
LONG TERM...MET
AVIATION...IRD
MARINE...JM/MET
FIRE WEATHER...
HYDROLOGY...JM/MET