Area Forecast Discussion
Issued by NWS Upton, NY-- Highlight Changed Discussion --
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FXUS61 KOKX 252141
Area Forecast Discussion
National Weather Service New York NY
541 PM EDT THU AUG 25 2016
A weak front will approach tonight. The front will then move
across the area on Friday, followed by high pressure this
weekend. A cold front will approach early next week, and may then
linger nearby until another cold front moves through Wednesday.
.NEAR TERM /UNTIL 6 AM FRIDAY MORNING/...
Initial weak shortwave could result in isolated showers/thunderstorms
this evening, moving west to east. Weak instability remains in
place through the night. A second shortwave tracks east, and a few
showers/thunderstorms could move in again after midnight.
However, most places will remain dry.
Otherwise, surface high pressure remains to the south as a weak
surface trough moves through. Southerly winds diminish as the
night progresses, and expect warm temperatures overnight due to
persistent southerly winds and broken to a times overcast cloud
Overnight lows will range from the upper 60s to the middle 70s.
There is a high rip current risk at the ocean beaches into
.SHORT TERM /6 AM FRIDAY MORNING THROUGH FRIDAY NIGHT/...
Upper ridge builds this time frame, with high pressure remaining
well to the south, and a weak cold front passing across the area
during the day Friday. 12Z model suite seems to be in good
agreement on a slightly faster cold frontal passage for western
zones. What this means is lower humidity levels during the
afternoon hours as winds shift to the west/northwest.
In spite of hot temperatures in vicinity of NYC metro/urban NJ,
slightly lower dew points will preclude 100 degree heat indices
that are needed for issuance of a heat advisory. As such, no heat
advisory is planned at this time.
Higher humidity will occur ahead of the front, over portions of
southern CT and Long Island. However, temperatures will be a tad
cooler there due to southerly winds ahead of the front.
As for rain, still would expect isolated to possibly scattered
coverage just along the front, per high resolution models. Best
chance during max heating and highest surfaced based instability
would be from southern CT southwestward across NYC metro and Long
Island for a time, with lowering chances as the afternoon
Dry Wx Friday night as much drier air moves in and the front
High temperatures Friday will range from the mid 80s along the
coasts of eastern Long Island and SE CT, to the lower 90s in and
around NYC metro.
At night, temps should fall into the 60s and 70s across the area,
still quite warm for this time of year, late summer.
.LONG TERM /SATURDAY THROUGH THURSDAY/...
Models continue to be in good agreement for the the long term
period. This period begins with weak surface high pressure over the
region, which pushes off the New England coast Sunday. Aloft, a
ridge will build in while a closed high is centered over the Mid-
A surface cold front approaches from the west late Sunday into
Monday, slowly crossing the region late Monday into early Tuesday
morning. This frontal boundary should then stall and meander
over/near the area into Tuesday night before the next cold front
pushes through on Wednesday.
As far as temperatures are concerned, with the lack of any real
strong cold air advection, it will be above normal through the
period, with normal highs now in the upper 70s to lower 80s. Highs
will be in the middle to upper 80s, with near 90 in the New York
City metro area possible on Monday. Humidity levels will be on the
high side, but nothing too extreme as the cold front does not make
it completely through the region. Heat index values should remain
below 95 through the long term.
One thing to watch is the tropical disturbance currently just north
of Hispaniola. If this system develops, it could get drawn up into
the frontal boundary that moves through our area Wednesday, after
potentially impacting the Gulf states. The operational models have
this system traveling the cold front and passing south of our region
late in the period. However, there is a great deal of uncertainty,
and if further model runs show this cold front to be slower to move
through, the area could be impacted with some rain from the system.
However, it is near the end of this time frame, so for now, it is
something to be watched.
.AVIATION /22Z THURSDAY THROUGH TUESDAY/...
-- Changed Discussion --A cold front over the Ohio Valley will slowly track towards the
region tonight, and through the area on Friday.
A few showers are possible across the NYC metro terminals and to the
north and west. No impacts expected. Although a few additional
storms are possible with the frontal passage on Friday, coverage is
expected to be too low at this time to include in the TAFs.
There is the potential for some stratus development off of the ocean
late tonight and Friday morning. If this does develop, ceilings
around 1000 ft can be expected. The best chance for occurrence is
east of Islip.
Southerly flow through this evening, veering to the west after the
passage of a pre-frontal trough on Friday, then northwest behind the
...NY Metro Enhanced Aviation Weather Support...
Detailed information, including hourly TAF wind component forecasts,
can be found at: http:/www.weather.gov/zny/n90
KJFK TAF Comments: No unscheduled amendments are expected.
KLGA TAF Comments: Occasional gusts to around 20 kt are likely
KEWR TAF Comments: A wind shift to the west and northwest with the
passage of showers occurred, and winds are expected to go back to
southerly around 22Z. Occasional gusts up to 20 kt are possible
KTEB TAF Comments: Occasional gusts up to 20 kt are possible through
KHPN TAF Comments: Occasional gusts up to 20 kt are possible through
KISP TAF Comments: Occasional gusts up to 20 kt are likely through
.Outlook for 18Z Friday through Tuesday...
.Rest of Friday...VFR outside of scattered showers and/or
thunderstorms. Winds becoming northwest by evening.
.Saturday-Sunday...VFR with sea breezes.
.Monday...Southwest flow. Potential cold frontal passage with a few
showers and thunderstorms.
.Tuesday...VFR with northwest flow.
-- End Changed Discussion --
Gusty southerly winds diminish this evening. SCA remains in effect
for the ocean waters, and added south shore bays due to the gusty
winds that are anticipated initially.
Winds do diminish ahead of a weak cold front late tonight and
through Friday. A shift to the west will occur behind the front
late Friday and Friday night from west to east. Rough ocean seas
will subside late tonight and through Friday night.
Sub-advy conds generally prevail otherwise through the day Monday.
However, potential remains for long period (generally periods of 10-
18 seconds) SE tropical swell on the ocean from Sunday through at
Seas could build to 5-6 ft mainly Monday night through Tuesday
night. Wind gusts should remain below 25 kt.
No significant widespread precipitation is expected into and
through the long term period.
-- Changed Discussion --CT...None.
NY...High Rip Current Risk until 9 PM EDT this evening for NYZ075-
MARINE...Small Craft Advisory until 6 AM EDT Friday for ANZ355.
Small Craft Advisory until 6 AM EDT Friday for ANZ345-350-353.
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