Area Forecast Discussion
Issued by NWS Upton, NY-- Highlight Changed Discussion --
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FXUS61 KOKX 290525
Area Forecast Discussion
National Weather Service New York NY
125 AM EDT Thu Sep 29 2016
High pressure over southern Quebec will maintain a moist northeast flow
off the Atlantic Ocean into the weekend as low pressure spins
over the Ohio Valley. The high departs as a frontal boundary moves
through this weekend. Another area of high pressure builds early
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
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Periods of light drizzle will continue to expand west across the
Patches of light rain advecting northeast across southern NJ will
move across the NYC Metro area and areas west and north of NYC
after 04z. Less than 1/10 of an inch of rain is forecast.
A moist cool night is on tap as NE winds 15-25 mph with higher
gusts continue along the coastal plain with lighter winds inland.
There is a high-end moderate risk of rip current development at
Atlantic ocean beaches Thursday as strong longshore currents
continue. The surf zone forecasts east of Moriches Inlet may need
to be upgraded to a high risk of rip currents Thursday.
The last scheduled surf zone forecast for this beach season is
this Friday,September 30
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.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM FRIDAY/...
Overall, expecting persistence with low clouds and light
precipitation and a small diurnal range in temps. Chance for
measurable QPF increases to categorical Thursday night as frontal
boundary starts moving north and over-running is enhanced.
Temps only top out in the Mid 60s - about 5 degrees or so below
.LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/...
Blocked upper level pattern noted for much of the period, with large
western Atlantic ridge holding Friday as cutoff upper low over the
Ohio Valley remains nearly stationary through Friday night.
Kicker upstream finally allows this cutoff to weaken and lift in
time this weekend. By early next week, the Atlantic ridge gets
pushed southeast as trough to the north lower heights across eastern
Canada. Meanwhile, cutoff as already mentioned weakens as it moves
east. However, differences arise by Tuesday as some solutions weaken
this trough much more than other forms of guidance. Ridge builds
east of the Mississippi by Wednesday.
At the surface, high pressure to the north remains nearly stationary
through Saturday as you would expect. Meanwhile, low pressure
underneath cutoff remains well to the west, with frontal boundary
located to our south. This front and triple point low lifts in time
this weekend with the changing upper level pattern, and will be
replaced by high pressure into early next week.
Deep southerly flow between the offshore high, and the low to the
west will lift over the warm front resulting in rain Friday and
Friday night. With ample lift, moisture and presence of upper
trough, expect rain chances to continue through the weekend.
The weather may be more showery in nature for the latter portion of
the weekend. Elevated weak instability could result in some thunder
at times as well.
Then mainly dry weather returns for the early to middle portion
of the upcoming week.
Below normal daytime temperatures Friday and Saturday are expected,
due to the clouds, rain and easterly flow. Nighttime lows however
remains slightly above normal. These daily temperatures will warm
closer to normal early next week. Developing east flow maintains
this near normal temperatures into the mid week period.
.AVIATION /06Z THURSDAY THROUGH MONDAY/...
A persistence type of forecast the next 24-36 hours with strong
high pressure to the north and nearly stationary low pressure
over the Ohio Valley. This will result in a prolonged period of
NE flow and overrunning clouds.
NE winds 10-15 kt with gusts in the 20-25 kt range will be in
place through much of the TAF period. Some locally higher gusts
to near 30 kt will be possible at times, especially along the
coast in the late afternoon/early evening hours Thursday.
Mainly MVFR cigs, but spotty IFR conditions are possible
overnight along with some light rain or drizzle.
.Outlook for 00Z Thursday through Monday...
.Thu Night-Sat Night...IFR/MVFR in rain. NE winds 15-20 kt with
gusts 25-30 kt through Fri Night. NW winds 10-15 kt with gusts
near 20 kt Sat-Sat Night.
.Sun-Mon...VFR. MVFR possible with showers Sunday.
Small Craft Advisory/SCA conds occurring on all waters and will
do so overnight. Expect winds to increase slightly on Thursday.
Expect minimal gales on the Ocean by late morning.
Seas build to around 5 ft on the open portions of the Sound and
10 ft on the Ocean.
Rough conditions continue Friday with high pressure to the north and
a warm front just south, resulting in gusty easterly winds.
Conditions will improve as the front lifts north this weekend, and
the pressure gradient weakens. High pressure will eventually build
behind this frontal system early next week.
The more significant rainfall is expect to not arrive until
Thursday overnight and continue into the weekend. Totals are
expected to average around 1".
The prolonged nature of the rain event should preclude any
A persistent moderate northeast flow through the week will
elevate water levels with an increase in astronomical high tides.
Water levels across the Atlantic Ocean facing south shore bays in
Nassau and Queens approached minor tidal flooding benchmarks with
this evening`s high tide cycles.
Minor coastal flooding is expected on Thursday in the most
vulnerable areas of the western Great South Bay. The region for
minor flooding will likely expand for Friday`s high tides.
Moderate levels of coastal flooding does not appear likely at this
time except for the most vulnerable regions of southern Nassau.
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NY...Coastal Flood Advisory from 6 AM to 10 AM EDT this morning for
Coastal Flood Advisory from 6 PM to 10 PM EDT this evening for
MARINE...Small Craft Advisory until 6 PM EDT Friday for ANZ330-335-338-
Gale Warning from 6 AM this morning to 6 PM EDT Friday for
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