746
FXUS61 KOKX 160511
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
111 AM EDT Mon Sep 16 2024
.SYNOPSIS...
High pressure remains in control through Monday night, before
gradually retreating north Tuesday into Tuesday night. A frontal
system slowly approaches from the southwest through mid- week
as high pressure drifts east in the northern Atlantic. The
frontal system remains in the vicinity towards the end of next
week. A back door cold front moves through Friday.
&&
.NEAR TERM /THROUGH TODAY/...
-- Changed Discussion --
Minimum temperatures have been lowered in this overnight update
due to increased radiational cooling. Otherwise, the forecast
remains on track.
With deep layered ridging in place with a 588 dm closed height
signature expect the dry weather to continue. For tonight with
high pressure aloft and at the surface expect mainly clear
skies. With lower dew points compared to earlier this weekend,
the column further down will be relatively drier. Thus the
prospects for patchy fog are less likely during tonight. With a
dome of high pressure and large scale subsidence mainly clear to
partly cloudy skies prevails. The winds will be light and
variable to NE in direction once again. Therefore expect
radiational conditions, but with the lack of a true cP air mass
and a very light onshore flow at times there is a floor as to
how much temperatures can fall as dew points will be in the 50s
and not the 40s.
With high pressure and large scale ridging holding this is
basically a persistence forecast through Monday. The winds once
again will be light and variable to begin the day, but with
solar insolation expect the winds towards late morning and mid
day to be more ENE at around 5 to 10 mph. It will be another
partly to mostly sunny day with temperatures at seasonable
levels for mid September.-- End Changed Discussion --
&&
.SHORT TERM /TONIGHT THROUGH 6 PM TUESDAY/...
For Monday night the upper level ridging begins to slowly break
down. More in the way of high clouds attempts to work in as low
pressure off the southeastern US coast begins to work NW. High
pressure however, especially when considering some subtle trends
in the guidance looks to be a bit slower in breaking down.
Therefore it remains partly cloudy to mostly clear Monday night
with a light E to NE flow remaining in place. With a bit more
moisture in the lower levels there should once again be a
reasonable chance to see some low stratus / patchy fog in many
of the lower lying rural locations like previous nights as of
late. Temperatures should average close to normal in outlying
areas, and a bit above normal in the more urban areas.
On Tuesday surface high pressure remains in place and doesn`t
really show much retreat until later in the day. A southerly
component to the flow aloft begins to get established during the
afternoon as the region gets on the outer edge of the northeast
quadrant of a closed low getting into the Lower Appalachians.
The mid levels may moisten up enough to produce more in the way
of mid level clouds, especially as the day progress. Thus a
partly cloudy to mostly cloudy day from NE to SW across the
region appears most likely. With more mid and upper level clouds
compared to lower level clouds, expect the clouds to mainly
filter out varying amounts of sun. Temperatures will once again
run right around seasonable levels. Dew point readings should
edge up in the 60s, especially along the coast as the day
proceeds. Introduced mainly slight chance PoPs later in the day
as questions remain how quickly any shower activity can get into
the area.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
Deep layered ridging with high pressure off the northwestern
Atlantic starts off the long term Tuesday night. The high slowly
drifts east through mid-week. At the same time, low pressure
over the Carolinas will slowly trek northwestward toward the
Ohio Valley through mid-week. The associated frontal system will
approach from the southwest and will begin to impact the region
Tuesday night
The low and frontal system get caught under the upper level
ridging over the eastern US from mid to late week and a
prolonged period of some unsettled weather is possible as weak
flow under the ridge will mean slow movement of these features.
Right now, it looks like the most likely period of rain is
Tuesday night through Wednesday night. There is a deep moisture
feed from the tropics and training possible. Dew points rise
well into the 60s Wednesday into Thursday and PWATs of
1.50"-2.25" are seen in some of the guidance. Of course, this is
all dependent on certain mesoscale features that cannot be
resolved at this point, but there is a low chance right now of
flooding, and the Weather Prediction Center has placed the
entire forecast area in a marginal risk of excessive rainfall
Wednesday into Thursday. With the previously mentioned
uncertainty, stuck close to the NBM and did not go any higher
than chance POPs through the long term.
Thereafter, the system finally begins to nudge south with the
approach of a back door cold front Thursday night, which now
looks to move through Friday. High pressure builds in from the
northeast next weekend.
Temperatures will average near seasonable, perhaps a degree or
so above Wednesday through Friday. Went slightly below guidance
on Wednesday and Thursday with cloudy skies and showers in the
forecast. Near normal to slightly below normal temperatures are
expected for next weekend with Canadian high pressure building
in from the northeast.
&&
.AVIATION /05Z MONDAY THROUGH FRIDAY/...
High pressure along the New England coast will gradually moves
east through Monday evening.
VFR. There is a low chance of patchy IFR/MVFR late tonight into
early Monday morning, 08Z to 13Z, however, this is less likely
than recent nights due to some drier low- level air in place.
Light E/NE to light and variable at the outlying terminals,
increase Monday morning and an E/SE flow redevelops by Monday
afternoon.
NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Low chance of patchy MVFR/IFR from 08-13Z Monday.
OUTLOOK FOR 00Z TUESDAY THROUGH FRIDAY...
Monday Night through Tuesday: Chance of MVFR or lower
conditions with low clouds/fog each late night/early morning,
otherwise VFR.
Wednesday through Friday: Chance of showers with MVFR or lower
conditions possible. ENE winds 10-15kt G15-20kt, mainly at the
coastal terminals.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90
&&
.MARINE...
No advisories are anticipated for the coastal waters to begin the
week. Ocean seas are likely to remain primarily at 3 to 4 ft with an
8 second period SE swell. Ocean seas may momentarily get close to 5
ft by towards Tuesday afternoon and evening, especially for the
western ocean. 5 ft waves are expected Tuesday night on the ocean
waters. More widespread 5 ft waves on the ocean waters are expected
Wednesday on a persistent easterly flow. The flow increases
Thursday night, and waves continue to build to 5 to 7 ft across
the ocean waters on Friday. Additionally, wind gusts of 25 to 30
kt are possible Friday into Friday night with the approach and
passage of a back door cold front.
&&
.HYDROLOGY...
No hydrologic concerns through the short term. An extended
period of rain is possible from Tuesday night through Wednesday
night with a tropical feed and training possible. There is a
great deal of uncertainty this far out. The Weather Prediction
Center has placed the entire forecast area in marginal risk for
excessive rainfall. One factor against flooding would be the
antecedent dry conditions over the last week.
&&
.TIDES/COASTAL FLOODING...
With an approaching full moon on the 17th, astronomical high tides
will be rising into the first half of the week, with water levels
potentially rising through the week. Continuous easterly flow will
help build seas and allow for some piling of water. Winds are
expected to remain generally light, near 10 kt or less. While some
of the guidance is showing water levels increasing, there is a
general consensus of keeping them below minor coastal flooding
benchmarks for the most part, although Stevens suggest minor
benchmarks being reached for the south shore bays and for western LI
Sound locations towards late Tue / Wed. However, this will likely
depend on the development of low pressure off the Carolina coast and
its eventual track early next week.
There is a moderate risk of rip current development at the ocean
beaches Sunday and Monday with an easterly flow developing.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...None.
&&
$$
SYNOPSIS...JE/JP
NEAR TERM...JE/JP/BR/MET
SHORT TERM...JE
LONG TERM...JP
AVIATION...MET
MARINE...JE/JP
HYDROLOGY...JE/JP
TIDES/COASTAL FLOODING...