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Area forecast discussion 
National Weather Service New York New York
640 am EDT Tuesday Sep 1 2015

Synopsis...
a back door cold front pushes just to the west this morning...then
retreats northeast as a warm front later today. Weak high pressure
then builds in tonight. A trough of low pressure approaches from
the northwest on Wednesday...then crosses the region Wednesday
night. A cold front then approaches from the northwest
Thursday...then moves through the tri-state Thursday night. High
pressure will then build in from the north for the weekend into
early next week.

&&

Near term /until 6 PM this evening/...
added patchy radiational fog until 13z/9 am...mainly west and
north of NYC including interior southern CT...generally
restricting visibilities 3-5 miles.

Deep layered ridging builds in today. Subsidence under the ridge
will keep cloud cover at a minimum.

For highs today used a blend of mixing down from 875-825 hpa per
BUFKIT soundings...with NAM 2-meter temperatures and a mixture of
mav/ecs/met guidance. Highs should be around 5-10 degrees above
normal...and generally a few degrees cooler than yesterday.

&&

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 /12z Tuesday through Saturday/...
a back door cold front works its way across the terminals early this
morning. Winds will be out of the north/northwest at less than 10 knots. Afternoon
sea breezes will develop at coastal terminals. Winds become light/vrb
this evening.

VFR...except a brief period of MVFR fog at kswf around daybreak.

New York 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. Amds
possible for timing of sea breeze...that could be off by +/- 1 hour.

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.

The afternoon kewr haze potential forecast is green...which implies
slant range visibility 7sm or greater outside of cloud.

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

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

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

Outlook for 09z Wednesday through Saturday...
Wednesday-Wednesday night...VFR.
Thursday-Thursday night...VFR. Isolated showers/thunderstorms
possible. Afternoon sea breezes probable.
Friday...VFR. East-northeast winds g15-20kt.
Saturday...VFR.

&&

Marine...
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...
it will be dry through tonight...and highly likely through
Wednesday as well.

No widespread significant rainfall is forecast from Wednesday
night through next weekend.

&&

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

&&

$$
Synopsis...gc/maloit
near term...gc/maloit
short term...maloit
long term...gc
aviation...mps
marine...gc/maloit
hydrology...gc/maloit

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