Area Forecast Discussion
Issued by NWS Upton, NY

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FXUS61 KOKX 242049

Area Forecast Discussion
National Weather Service New York NY
449 PM EDT WED AUG 24 2016

High pressure remains south of the area through Thursday. A
weakening front will approach Thursday night. The cold front
moves across the area on Friday. High pressure returns this
weekend. Another cold front approaches early next week and may
linger near the area through Wednesday.


Upper ridge remains anchored to our south tonight, as the area
remains on the southern edge of the westerlies.

Generally clear skies are anticipated.

Expect temps tonight to run a little warmer than the past couple of
nights as the airmass modifies. Lows will range from around 60, to
around 70 in and around NYC.


Ridge remains anchored to the south Thursday and Thursday night as
the area remains on the southern edge of the westerlies.

A weak trough approaches from the west. Expect an increase in mid
and higher level clouds from the west late in the day, with a
good amount of sunshine all day further east.

Will cap pops to slight chance, mainly for western sections late in
the day. Slight chance pops spread east at night. High resolution
models indicate spotty showers moving across the area at night. NWP
model solutions output minimal QPF, or keep conditions dry for the
most part.

High temps will range from around 80 over eastern coastal
locations, to the upper 80s in northeast NJ.

At night, persistent southerly flow along with plenty of clouds will
result in warm temps, with a much smaller range in low temps, upper
60s to middle 70s.


The latest NWP model suite is in good agreement through this
weekend, then they begin to diverge a bit early next week. A strong
upper anticyclone will build towards the region Friday and then
remain over the Middle Atlantic this weekend. The ridge may begin to
shift south and weaken a bit on Monday as a northern stream
shortwave traverses across SE Canada. Differences arise with the
timing and how much the ridge breaks down. Differences continue
through the middle of next week with how much ridging rebuilds

A weak cold front will move through late Friday. Friday will be hot
and humid with temperatures surging into the upper 80s and lower
90s. Heat indices will reach the middle 90s and could reach the
upper 90s if dew points stay higher than forecast in the afternoon.
This is possible if more moisture pools along and ahead of the cold
front. However, thermal profiles show potential mixing up to around
850 hPa in the afternoon which should help to lower dew points into
the upper 60s in the afternoon. There will be a good amount of dry
air in the upper atmosphere as heights actually will rise.
Instability is also marginal as there may be a cap around 15kft, so
have lowered PoPs to just slight chance.

High pressure builds down from SE Canada this weekend with a light
northerly flow and slightly cooler air. The most noticeable
difference will be less humidity as dew points generally in the
lower and middle 60s. This will preclude the need for a heat
advisory in NYC since heat indices should only be in the upper 80s
this weekend, close to actual air temperatures.

Another cold front approaches late Sunday night into Monday. The
main shortwave forcing passes well to the north so have mainly kept
PoPs at slight chance with chance PoP across the interior. The
boundary may then stall near the area Tuesday into Wednesday.
This will all be tied to how strong the ridge aloft ends up and if
the upper jet stays well to the north leaving the boundary behind.
Overall, above normal and humid conditions should continue next


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. Sea breezes have
developed and moved inland. Winds become light SW tonight, before
increasing once again on Thursday.

     NY Metro Enhanced Aviation Weather Support...

Detailed information, including hourly TAF wind component forecasts,
can be found at: http:/

KJFK TAF Comments: No unscheduled amendments expected

KLGA TAF Comments: No unscheduled amendments expected

KEWR TAF Comments: The sea breeze may remain in the vicinity of the
terminal with winds at times going back to 200 to 210. The sea
breeze weakens around 23Z with wind becoming 210.

KTEB TAF Comments:  The sea breeze may remain in the vicinity of the
terminal with winds at times going back to 200 to 210. The seabreeze
weakens around 23Z with wind becoming 210.

KHPN TAF Comments: Weak sea breeze moved through around 20Z and may
weaken around 00Z with winds becoming light and variable.

KISP TAF Comments: No unscheduled amendments expected

.Outlook for 18Z Thursday through Monday...
.Thursday afternoon-Friday...VFR. A slight chance of showers, with
isolated thunderstorms possible Friday. Lo chance of MVFR in
.Friday night-Monday...VFR.


High pressure remains offshore, and southerly wind flow will prevail
tonight through Thursday night. Speeds increase late in the day
Thursday, and winds over the ocean waters may approach SCA
criteria, or frequent gusts to 25 kt. Not enough confidence in
this actually occurring, so no plans to issue a SCA at this time.

Seas build to 4 feet across the ocean waters late in the day and
into Thursday night. Guidance suggests 5 Footers are not out of
the question. If that becomes more clear, later shifts may
consider issuance of a SCA due to the borderline winds and seas.

For non ocean waters, seas/waves should remain 2 ft or less.

There remains the potential for a tropical swell on the waters late
this weekend and early next week. Seas could build to around 5 ft
with this long period SE swell.

Winds and seas should fall below SCA levels through the first half
of the weekend. Then SCA for hazardous seas is possible on the ocean
Sunday into Monday as seas build close to 5 ft due to a long period
SE swell.


No significant widespread precipitation is expected into next week.




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