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000 
FXUS61 KOKX 181127
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
727 AM EDT Wed Oct 18 2017

.SYNOPSIS...
High pressure will remain in control through the weekend, with a
prolonged period of fair weather. An approaching cold front will
bring a chance of rain for the beginning of next week.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Skies will be sunny as surface high pressure dominates and as an
upper trough passes east, with rising heights aloft. A 
subsidence inversion between 875-900 mb will limit mixing, still
with warm air advection temps should reach the upper 60s and
lower 70s this afternoon.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
As the upper ridge passes east, WAA aloft ahead of another
transient upper trough should lead to some high clouds late
tonight into Thu morning, with the sky remaining mostly clear 
overall. Lows tonight should be mostly in the 40s and 50s, with 
only some isold upper 30s well inland. 

The subsidence inversion associated with the sfc high as it 
sinks to the south will be a little stronger, with mixing only 
to 900-925 mb. This despite plenty of sunshine will yield temps
only a little warmer than those expected for today, reaching
70-75, about 10 degrees above average for this time of year.

&&

.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
High pressure will continue to dominate through Saturday. The 
high drifts offshore late Saturday, with return flow developing 
for the second half of the weekend. This will produce an 
increase in humidity across the area, particularly from Long 
Island to Connecticut. Large diurnal spreads of 20-25 degrees 
through Saturday are likely due to the dry air mass. High 
temperatures will remain several degrees above average. 
Southwesterly flow will pick up Monday and Tuesday, as the area 
starts to get squeezed from an approaching cold front to the 
west, and high pressure over the Atlantic. The potential exists 
for the Gulf of Mexico to get tapped with this excess moisture 
getting transported into the forecast area. Monday and Tuesday 
could be quite humid as a result. As far as actual rain chances,
there are two main shots to contend with. The first is with the
approach of a residual convective boundary racing ahead of the 
main system. Both the GFS and ECMWF have this feature. This has 
the potential to produce locally heavy showers as it interacts 
with the deepening moisture on Monday. As the main upper level 
system gets here Tuesday or slightly later, this produces 
significant lift and therefore a solid round of moderate to 
heavy rain. Both the ECMWF and GFS again are pointing in the 
same direction. The only limiting factor would be if the leading
boundary shunts the deeper moisture out to sea. This however in
not what the models are currently signaling.

&&

.AVIATION /12Z WEDNESDAY THROUGH SUNDAY/...
High pressure builds to the south of Long Island into tonight.

Very high confidence in VFR through the TAF period.

Winds become W-WNW at around 10 kt throughout by mid morning. 
Winds then slowly back to the SW in the afternoon. Seabreezes 
are possible at coastal terminals mid-late afternoon. There is 
a chance for isolated gusts to around 15kt at city terminals 
late this afternoon. Winds become light and variable during the 
late afternoon/tonight. 

     NY Metro Enhanced Aviation Weather Support...

Detailed information...including hourly TAF wind component fcsts
can be found at: 
http:/www.weather.gov/zny/n90

KJFK TAF Comments: Timing of changes in wind speed and direction
could be off +/- 1-2 hours. There is moderate confidence in a 
seabreeze this afternoon. There is also the possibility for 
isolated gusts to around 15kt late this afternoon/early this 
evening.

The afternoon KJFK haze potential forecast is green, which 
implies slant range visibility 7SM or greater outside of cloud.

KLGA TAF Comments: Timing of changes in wind speed and direction
could be off +/- 1-2 hours. There is low-moderate confidence in
a seabreeze this afternoon. There is also the possibility for 
isolated gusts to around 15kt late this afternoon/early this 
evening.

The afternoon KLGA haze potential forecast is green, which 
implies slant range visibility 7SM or greater outside of cloud.

KEWR TAF Comments: Timing of changes in wind speed and direction
could be off +/- 1-2 hours. There is also the possibility for 
isolated gusts to around 15kt late this afternoon/early this 
evening.

The afternoon KEWR haze potential forecast is green, which 
implies slant range visibility 7SM or greater outside of cloud.

KTEB TAF Comments: Timing of changes in wind speed and direction
could be off +/- 1-2 hours. There is also the possibility for 
isolated gusts to around 15kt late this afternoon/early this 
evening.


KHPN TAF Comments: Timing of changes in wind speed and direction
could be off +/- 1-2 hours. There is also the possibility for 
isolated gusts to around 15kt late this afternoon/early this 
evening.

KISP TAF Comments: Timing of changes in wind speed and direction
could be off +/- 1-2 hours. There is moderate confidence in a 
seabreeze this afternoon.

.OUTLOOK FOR 12Z THURSDAY THROUGH SUNDAY...
.Thursday-Thursday night...VFR. SW-W winds G15-25kt possible 
Thursday and Thursday evening.
.Friday-Friday night...VFR. NW-N winds G15-25kt possible
Friday afternoon and evening.
.Saturday-Saturday night...VFR.
.Sunday...VFR. SW winds G15-20kt possible.

&&

.MARINE...
High pressure settling to the south will produce a WSW flow 
with gusts up to 20 kt early this morning. Another period of 
increased WSW flow should bring winds and seas on the ocean 
close to advy thresholds Wed night, possibly briefly ramping to
advy levels on Thu. Quiet conditions expected otherwise.

&&

.HYDROLOGY...
No hydrologic issues expected through the weekend. Locally heavy
rain is possible during the beginning of next week.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...None.

&&

$$
SYNOPSIS...JMC/Goodman
NEAR TERM...Goodman
SHORT TERM...Goodman

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