000
FXUS61 KOKX 171456
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
1056 AM EDT Mon Apr 17 2023
.SYNOPSIS...
A cold front will move across the region today. An area of low
pressure will remain over eastern Canada and into the northeast
tonight into Tuesday. High pressure builds in for Tuesday night into
Wednesday, and moves offshore Wednesday night. A warm front slowly
approaches Thursday. Low pressure impacts the region Friday with a
cold front passing through the area Saturday. Low pressure remains
nearby Sunday.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
-- Changed Discussion --
Showers continue north of a weak low just offshore to the south
as well as to the east of the weak low front currently aligned
north to south in the vicinity of the NY/CT border. Have
adjusted PoPs accordingly. Also lowered the high temp forecast
by a few degrees east of where the cold front currently is as
clouds holding on longer will probably prevent highs reaching
the previous forecast.
Fog continues mainly east of the Hudson River and have extended
an SPS to address lowering visibility - locally down to 1/4
mile.
Drier conditions start to work into the area this afternoon/evening
as the flow becomes more SW. Some gusts to 20 mph will become
likely by late afternoon.
Highs today for much of the area will remain in the 60s, however a
few spots in the NYC/NJ metro areas could touch 70. Further east,
across the forks of LI and eastern CT, temperatures may struggle to
reach 60.-- End Changed Discussion --
&&
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
Surface high pressure starts to build into the area tonight, however
an upper level trough remains over the area. Expect dry conditions,
however there could be some mid level clouds around. Winds will be
from the W/SW, and it could be breezy at times.
The upper level trough remains over the area for a good part of the
day, before finally lifting north late. The dry and breezy
conditions will continue, with gusts to near 25-30 mph especially
closer to the coast.
Temperature tonight will fall into the 40s, with highs on Tuesday in
the 50s. A few lower 60s will be possible in NJ.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
No real significant changes to the long term and stuck close to the
NBM during this period.
Heights begin to rise Tuesday night as the upper low weakens and
track north, and a more amplified ridge builds to the west, into the
Great Lakes region by Wednesday morning. Weak low level cold
advection ends toward Wednesday morning, and warm advection then
sets up during Wednesday as a warm front approaches Wednesday night.
Moisture will be limited with the front, and the best frontal
forcing and frontolysis remains to the north. There is some
uncertainty in the global guidance as to whether or not any
precipitation will occur with the frontal forcing Wednesday night
into Thursday, and leaning toward the NBM probabilities will keeping
the area dry. The warm front continues to look to remain to the
south of the region into Friday as the more amplified ridge slows
the eastward progression of the next system. Still bringing in
chances for precipitation late Friday and continue to mention a
slight chance of thunder inland with weak CAPE and surface based
instability. Also mentioned convection Saturday afternoon across the
region as the cold front approaches although CAPE and instability
will be more elevated. The front will be slow to move through the
region as the upper low remains well to the west, and precipitation
may be possible through Sunday with the potential for a wave to
develop Sunday along the offshore cold front.
&&
.AVIATION /15Z MONDAY THROUGH FRIDAY/...
-- Changed Discussion --
A cold front passes across the area this morning. A trough moves
through this evening.
The front is moving through western terminals, with winds shifting
at KEWR as of 1430z. This will continue to advance east over the
next couple of hours, with a W/WSW flow then expected through the
TAF period. IFR conds from low stratus and fog continue to linger
ahead of the front, though cigs/vsbys begin to rise later this
morning and into early this afternoon before the front clears and
winds increase, becoming VFR by 18 or 19z for most, and perhaps a
couple of hours later for eastern terminals KISP, KBDR, and KGON.
VFR expected for all terminals after 20Z.
Winds mainly E-ESE at less than 10 kt through this morning will
begin to turn more WSW behind the cold front then around to the W in
the evening as a trough moves through. Gusts of 20 to around 25 kt
are possible in the afternoon for most terminals.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Amendments likely for changing flight categories into early
afternoon.
Timing of improvement to VFR may be off by an hour or two.
Forecast confidence increases after the cold frontal passage early
this afternoon.
OUTLOOK FOR 12Z TUESDAY THROUGH FRIDAY...
Tuesday-Thursday: VFR with W flow.
Friday: VFR then MVFR with a chance of showers in the afternoon.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90.-- End Changed Discussion --
&&
.MARINE...
-- Changed Discussion --
Fog will continue to impact the waters, and a dense fog
advisory has been extended into this afternoon. Otherwise, winds
and seas will remain below SCA criteria thru Mon. Seas could
come close to reaching criteria tonight with a persistent WSW
flow, however for now, will keep seas just below. Any SCA
conditions tonight looks to be marginal at best.
With a gusty westerly flow behind departing low pressure Tuesday
wind gusts should reach 25 ft at least on the near shore waters and
seas may reach 5 ft. Have gone with a SCA for Tuesday and Tuesday
evening for all waters, however thinking the majority of the 25 kt
winds will be right along the coastline where there will be better
mixing. Winds and seas fall Tuesday night, with high pressure over
the area Wednesday, and moving offshore Wednesday night, winds and
seas across all the forecast waters will remain below advisory
levels Tuesday night into Friday night. A strengthening southerly
flow out ahead of an approaching cold front may bring some gusts
close to or exceeding SCA criteria late in the day Saturday. Waves
build on Saturday on the ocean, and may approach 5 ft late in the
day Saturday as well.-- End Changed Discussion --
&&
.HYDROLOGY...
No hydrologic impacts are expected this week.
&&
.TIDES/COASTAL FLOODING...
-- Changed Discussion --
Based on observations from the most recent high tide cycle and
anticipated levels with a slightly higher astronomical tide for
the next high tide cycle, have issued a Coastal Flood Statement
for the south shore back bays of Nassau County for this
evening`s high tide cycle. A few sites should just touch or go
slightly over flooding benchmarks. The only other areas that
could come close would be the south shore of Queens, lower NY
Harbor, and the westernmost areas of LI Sound, however levels
are expected to remain just below flooding benchmarks.
Astronomical tides then lower for subsequent cycles, so no
flooding concerns after this evening.-- End Changed Discussion --
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
CT...None.
NY...None.
NJ...None.
MARINE...Dense Fog Advisory until 5 PM EDT this afternoon for ANZ331-
332-335-340-345-350-353.
Small Craft Advisory from 6 AM to 8 PM EDT Tuesday for ANZ331-
332-335-338-340-345-350-353-355.
Dense Fog Advisory until 1 PM EDT this afternoon for ANZ338-
355.-- End Changed Discussion --
&&
$$
SYNOPSIS...BC/JP
NEAR TERM...BC/JC
SHORT TERM...BC
LONG TERM...JP/MET
AVIATION...JP
MARINE...BC/JC/JP
HYDROLOGY...BC
TIDES/COASTAL FLOODING...JC