Area Forecast Discussion
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FXUS61 KOKX 241616
Area Forecast Discussion
National Weather Service New York NY
1216 PM EDT WED AUG 24 2016
High pressure will remain centered just south of the area through
Thursday. A weakening front will approach Thursday night into
Friday, and move across Friday night. High pressure will follow
for the weekend. A cold front will slowly move through on Monday.
.NEAR TERM /THROUGH TONIGHT/...
Forecast is on track. The surface high just to the south will
continue to dominate, with mainly clear skies. Winds become
southerly, with sea breeze enhancement along the coast, then veer
SW and diminish tonight as the sea breeze circulation weakens.
Temperatures on track and expect high temps to be a little warmer
than the warmest MOS guidance, with mid and upper 80s most places,
and lower 80s along the south shore of Long Island and SE CT.
Lows tonight as the air mass modifies are a little warmer than
GFS MOS guidance in most spots, with lower 70s invof NYC, 60s most
elsewhere, and upper 50s in the Long Island Pine Barrens and some
interior spots well NW of NYC.
.SHORT TERM /THURSDAY/...
As a weak upper trough approaches, should see mid sct-bkn mid level
clouds move in fairly quickly Thu morning mainly from NYC
north/west. Low levels remain fairly dry during this time and
instability looks confined to the boundary layer, so do not
expect much if any in the way of precip in these areas, maybe
slight chance of a late day shower especially well inland invof a
subtle lee trough developing near Orange County and NW NJ. Skies
farther east should remain mostly sunny with sfc ridging holding
on through the day. Afternoon sea breezes should be stronger,
likely sustained at 15-20 mph along the south shore of Long
Island and NYC, which may increase the rip current risk further.
High temps should be fairly similar to those forecast for today,
with mid/upper 80s most places and lower 80s along south facing
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
NWP guidance is in good agreement across North America at H5 into
Saturday, then differences begin to develop with the progression
and amplitude of a northern stream trough tracking through the
northern plains in response to downstream ridging. Meanwhile, a
strong upper anticyclone over the Tennessee Valley Thu night will
drift toward the Mid Atlantic coast by Sat night.
At the surface, a weak front will approach Thu night and track
across the area on Fri. Low chc PoP during the day Fri at best
although a warm nose around 15kft may preclude most tstm
development, with mainly sct shower activity expected. The front
passes with dry weather for the weekend, but not much relief from
the heat. May have multiple days of 90 degree readings, especially
in NYC and areas N and W. GFS temps seemed a low on Sat and
Sunday, so sided closer to the EC guidance. Not anticipating a
heat advy for NYC attm, since Fri appears to be the only day we
could reach mid to upper 90 heat indices due to moisture pooling
ahead of the frontal boundary. Dewpoints should be around 5
degrees lower on Sat behind the boundary, so heat indices are only
expected to be in the lower 90s. Potential is there, just low
attm. Will monitor.
A cold front slowly approaches Sunday night and Monday, although
best mid level forcing passes to the north. Chc PoP across the
interior seems plausible on Mon, and kept mention of thunder
confined to NW areas based on capped mid levels. This boundary
may stall near the area on Tue as the LFQ of an upper level jet
streak passes through, possibly triggering additional
.AVIATION /16Z WEDNESDAY THROUGH SUNDAY/...
High pressure slowly slides offshore into this evening and remains
in control through tonight.
VFR through the TAF period.
Light westerly or variable winds...become S/SW this afternoon.
Sea breezes develop at coastal terminals. Sea breeze front may
have trouble making it completely through KEWR and KTEB...but
instead battle an occasionally gusty SW flow and waver in the
vicinity of the terminal. Winds become light SW tonight.
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: Southerly sea breeze development expected between
16z and 18z.
KLGA TAF Comments: Southerly sea breeze development expected between
19z and 21z.
KEWR TAF Comments: SE sea breeze development possible between 19z and
22z. Wind direction could waver btwn sw and se during this time.
Occasional SW gusts to 15 kt possible in the afternoon.
The afternoon KEWR haze potential forecast is GREEN...which implies
slant range visibility 7SM or greater outside of cloud.
KTEB TAF Comments: S sea breeze development possible between 19z and
23z. Wind direction could waver btwn sw and s during this time.
KHPN TAF Comments: Weak S sea breeze development possible aft 21z.
KISP TAF Comments: SSW sea breeze development expected between
17z and 19z.
.Outlook for 12Z Thursday through Sunday...
.Thursday-Thursday night...Mainly VFR. Slight chance of
afternoon/nighttime showers. Best chances North and West of NYC. S
winds gusts 15-25kt possible Thursday aft/eve.
.Friday...Mainly VFR. Chance of afternoon showers and thunderstorms,
with brief MVFR conditions possible.
Tranquil winds and seas through the day today, with local
enhancement of sea breezes. There is still a low to medium chance
that ocean seas could reach SCA criteria some time late day Thu
night into Fri ahead of an approaching front. There is also
suggestion of tropical swell encroaching on the waters early next
week, with waves building to at least 4 ft by Sunday. Otherwise,
winds and seas should remain below SCA criteria into early next
No significant widespread precipitation is expected.