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Area forecast discussion 
National Weather Service New York New York
147 PM EDT Tuesday Sep 1 2015

Synopsis...
weak high pressure builds in through tonight. A trough of low
pressure approaches from the northwest Wednesday...crossing the
region Wednesday night. A cold front approaches from the
northwest Thursday...moving through the tri-state Thursday night.
High pressure builds in from the north for the weekend into early
next week.

&&

Near term /until 6 PM this evening/...
scattered cumulus have developed across much of the region under
weak subsidence and full sun initially. Temperatures mainly on
track...with some locations a degree or two higher than forecast.
Dew points were lowering with a combination of drier air moving in
and mixing. Sea breezes were developing along the coasts and will
halt temperature rises there.

&&

Short term /6 PM this evening through 6 PM Wednesday/...
the axis of the deep layered ridge slides to our east by late
tonight/early Wednesday morning. Subsidence under the ridge will
continue to promote minimal if any cloud cover. For lows tonight
used a blend of mav/met/ecs guidance with NAM 2-meter temperatures
mixed in over urban areas. Lows should be 5-10 degrees above
normal...with the largest departure in urban areas.

The flow aloft generally GOES zonal over the area
Wednesday...with a southern stream shortwave passing to the
S...with the flow becoming west-northwest-northwest aloft by late Wednesday
afternoon. The general model consensus is that the shortwave
passes to far to the SW/S to cause any precipitation...so went
with a dry forecast for now. However...the CMC-regional model does
indicate the possibility for some showers mainly west of NYC...but
this appears to be an outlier solution at this time.

For highs Wednesday used a blend of met/ecs/mav guidance...mixing
down from 975-850 hpa per BUFKIT soundings and NAM 2-meter
temperatures. Highs should be around 5-10 degrees above
normal...and generally within a degree or so of those today. Heat
indices peak out in the lower 90s in urban areas Wednesday
afternoon.

&&

Long term /Wednesday night through Monday/...
prepare for increasing drought and fire danger weather through
next Tuesday.

Wednesday night-Thursday night...heat and humidity will come to an end as
forecast models continue to show a digging upper level short wave
sliding down the upstream ridge. This will allow a building high
pressure system over southeast Canada to push a stronger cold front south
across the region Thursday night. This front will be preceded and
accompanied by widely scattered-scattered thunderstorms. This will be the only chance for
rain in the long term.

Fri-Sunday...a refreshing maritime polar air mass on east winds
replaces the persistent maritime tropical airmass. Temperatures will
average near normal...almost 10 degrees cooler than it has been.

With yet another dome of high pressure moving directly overhead into
early next week...precipitation deficits along with fire danger will
continue to gradually increase.

&&

Aviation /18z Tuesday through Sunday/...
VFR with high pressure over the region.

Light north/NE winds except along the coast where sea breezes have
developed. Winds become light and variable this evening and
overnight. Southerly winds develop once again late Wednesday
morning.

A period of MVFR visibilities is possible after 08z Wednesday at
kswf/khpn/kgon.

... Metropolitan enhanced aviation weather support...

Detailed information...including hourly taf wind component forecasts
can be found at: http:/www.Erh.NOAA.Gov/zny/n90 (lower case)

Kjfk fcster comments: moderate confidence in the wind forecast.

Klga fcster comments: moderate confidence in the wind forecast.
Amds possible for timing of sea breeze...that could be off by +/-
1 hour.

Kewr fcster comments: moderate confidence in the wind forecast.
Amds possible for timing of sea breeze...that could be off by +/-
1 hour.

Kteb fcster comments: moderate confidence in the wind forecast.

Khpn fcster comments: moderate confidence in the wind forecast.

Kisp fcster comments: moderate confidence in the wind forecast.



Outlook for 18z Wednesday through Sunday...
Wednesday-Wednesday night...VFR.
Thursday-Thursday night...VFR. Isolated showers/thunderstorms
possible. Afternoon sea breezes probable.
Friday...VFR. East-northeast winds g15-20kt.
Saturday and Sunday...VFR.

&&

Marine...
wind and seas forecast on track.

A weak pressure gradient over the region will generally keep
winds at under 10 knots through Thursday night. Seas on the coastal
ocean waters will be 3 feet or less and on the non-ocean waters 1 feet
or less as a result through Thursday night.

Thursday afternoon and evening...there is a slight chance of
thunderstorms with the approach of a cold front.

The next chance for Small Craft Advisory level winds of 25 knots and
seas of 5 feet across the Atlantic coastal waters will be Friday
into Saturday following the passage of a cold front. Wind gusts to
25 knots are possible on Long Island Sound and nearshore waters from
Friday into Saturday as well.

&&

Hydrology...
dry through Wednesday.

No widespread significant rainfall is forecast Wednesday night
through early Friday. Then dry weather again from later Friday
through Tuesday.

&&

Okx watches/warnings/advisories...
CT...none.
New York...none.
New Jersey...none.
Marine...none.

&&

$$
Synopsis...met
near term...met
short term...maloit
long term...gc
aviation...British Columbia
marine...gc/maloit/met
hydrology...met

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