844
FXUS61 KOKX 171752
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
1252 PM EST Sun Nov 17 2024
.SYNOPSIS...
Broad high pressure will build over the region today, followed
by a weak cold frontal passage on Monday. High pressure returns
for Tuesday. A complex low pressure system will affect the area
Wednesday night into the weekend.
&&
.NEAR TERM /THROUGH TONIGHT/...
A few high thin clouds over the region will increase as upper
ridge axis nears the coast this afternoon. With a stronger
pressure gradient force across Connecticut and Long Island
with high pressure to the west and low pressure offshore,
northerly winds have been a little stronger and gustier than
forecast. Temperatures have been running a couple of degrees
warmer and raised hourlies and highs for today based on the
current forecast and the higher MOS temperatures. Otherwise, dry
weather continues into tonight.
High pressure centered west of the region builds to the south
of the cwa today. Generally light NW flow backs to the W thru
the day. With H85 flow picking up to around 15kt, this may be
enough to hold off the aftn sea breeze. Although not in the
model blends, would not be surprised to see it develop along the
immediate S shores of CT and LI.
The mid and high clouds overspread the area tngt ahead of a
cdfnt. Timing looks to have sped up a bit, with the fropa before
12Z Mon. Stayed with the NBM for temps with the cloud cover
limiting the radiational cooling component.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
NW winds kick up again by 15-18Z with the cdfnt likely thru the
cwa per the modeling. H85 winds increase to around 30kt per the
GFS and NAM, so gusts around 25 mph seams reasonable. Increased
winds in the grids above the model blends and NBM to indicate
this. Falling temps aloft could allow for sct cu to trigger in
the aftn. Deep mixing however will allow for highs well abv
climo. By Mon ngt, some stratus may attempt to bleed in from the
NW, but extensive low cloud cover is not expected attm with the
downslope flow and dry airmass. WAA aloft Tue will lead to
increasing clouds thru Tue ngt. The cloud cover, along with
weaker mixing, is progged to keep temps cooler than Mon despite
a warmer airmass overall. Stuck with the NBM here for temps.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
Models in good agreement with an anomalously deep closed upper low
(2-3 standard deviations below normal heights) digging into the
Ohio/Tennessee Valley Wed Night into Thu, lifting into the NE US on
Friday, and then stalling over the NE US into the weekend. Global
models have trended over the past 24 hours with a weaker surface low
development over the Great Lakes and a stronger secondary low taking
shape right over us late Wednesday night into Thursday. This will
therefore be the period when rainfall chances will be at the
highest. Can`t even rule out an isolated thunderstorm with the
strengthening low center passing through coinciding with a little
elevated instability. NBM probability of 1+ inches of rain Weds
night through Thursday has increased to 30-50%, with deterministic
models in pretty good agreement that we pick up 0.75 to 1.50 inches
of rain during this time.
Models begin to diverge thereafter regarding the track of the closed
H5 low and attendant surface low to our north. Chances of showers
will remain through Saturday with a cyclonic flow remaining aloft.
It could be quite breezy as well during this period, depending on
the position of the storm`s center.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
-- Changed Discussion --
High pressure settles nearby this afternoon, then settles just to
the south tonight. A weak cold front approaches tonight and passes
through Monday morning. Weak high pressure builds Monday afternoon
and evening.
VFR. NW winds 5-10kt backing more westerly this afternoon.
...NY Metro (KEWR/KLGA/KJFK/KTEB)TAF Uncertainty...
There is a chance all 4 terminals prevail from the SW for a few
hours late afternoon into the early evening.
OUTLOOK FOR 18Z MONDAY THROUGH FRIDAY...
Monday afternoon...VFR. NW gusts around 20kt.
Tuesday...VFR.
Wednesday...VFR during the day. MVFR/IFR at night with rain along
with E-SE gusts around 25kt.
Thursday...MVFR/IFR with rain in the morning, then mostly MVFR in
the afternoon with a chance of showers. Gusts out of the W possible
later in the day and at night.
Friday...Pockets of MVFR early, otherwise VFR prevails with gusty
WNW winds.
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 gusts were a little stronger throughout the morning
across the forecast waters as a strong pressure gradient force
remains between high pressure to the west and offshore low
pressure. This will be weakening through the afternoon as the
high builds to the south.
Winds and seas blw sca lvls thru tngt. There is a chance winds
pick up to around 25 kt on Mon behind the cold front, before
diminishing again Mon ngt. Winds and seas again blw sca lvls
Tue.
There will then be a prolonged period of at least SCA conditions for
all waters Wednesday night into the weekend with a storm lingering
nearby.-- End Changed Discussion --
&&
.FIRE WEATHER...
-- Changed Discussion --
NW winds backing to the W this afternoon in the 5-12 mph range.
Min RH 20-30 percent. Winds shift to the NW Mon mrng behind a
front, with gusts around 25 mph possible in the aftn. Min RH
around 30-40 percent.-- End Changed Discussion --
&&
.HYDROLOGY...
Rainfall Wednesday night through Thursday is shaping up to be
in the range of 0.75 to 1.50 inches. Although most of this may
fall in less than a 6-12 hour period, there are no significant
hydrologic concerns at this time.
&&
.TIDES/COASTAL FLOODING...
-- Changed Discussion --
A gradual lowering of total water levels is expected through
Monday as astronomical tides and surge slowly fall. This will
still result in another round of widespread minor flooding along
coastal Westchester and Fairfield counties. Localized minor
coastal flooding for much of Suffolk County, and coastal New
Haven County into early this afternoon.
Localized minor flooding will likely be mainly confined to
Queens/Nassau County southern bays and Southern Westchester/SW
CT for the Monday morning high tides.-- End Changed Discussion --
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...Coastal Flood Advisory until 1 PM EST this afternoon for
CTZ009.
NY...Coastal Flood Advisory until 1 PM EST this afternoon for
NYZ071.
NJ...None.
MARINE...None.
&&
$$
SYNOPSIS...JMC/JC
NEAR TERM...JMC/MET
SHORT TERM...JMC
LONG TERM...JC
AVIATION...JE
MARINE...JMC/JC
FIRE WEATHER...
HYDROLOGY...JC
TIDES/COASTAL FLOODING...