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Area forecast discussion 
National Weather Service New York New York
819 PM EDT Wednesday Sep 2 2015

Synopsis...
a weak trough of low pressure gives way to weak high pressure to
the northwest tonight. A cold front will then approach from the
north on Thursday and moves across late Thursday afternoon into
Thursday night. High pressure builds down from southeastern
Canada late Thursday night into Friday...then remains in control
through the middle of next week.

&&

Near term /until 6 am Thursday morning/...
a surface trough across the area this evening gradually weakens
and gives way to weak high pressure building in from the northwest. This
will allow winds to become light and variable tonight. The main
forecast challenge will be whether or not fog develops and the
coverage. Last night it was primarily over eastern Li and southeast CT.
However...dew points are a bit higher tonight...this may allow for
more coverage.

Conditions will remain warm and humid with dew points in the 60s
and similar lows.

&&

Short term /6 am Thursday morning through Thursday night/...
the upper shortwave passes through upstate New York and off the New
England coast Thursday through Thursday night. Late Thursday the
upper ridge builds into the region as the upper trough shifts off
the Canadian and northeast coast. At the surface a cold front pushes
through by late in the day Thursday into Thursday night. The upper
shortwave is weak with surface instability and cape of 500 to 1200
j/kg. So will continue with chance probability of precipitation for showers and
thunderstorms late Thursday afternoon into Thursday evening. By 06z
Friday instability decreases along with cape and will transition to
just showers with an isolated thunderstorm.

&&

Long term /Friday through Wednesday/...
gradually increasing drought and fire weather concerns through the
period.

Models in good agreement with upper ridging building into the region
Friday into the weekend...gradually flattening next week.

Canadian high pressure builds south-southwest across the region Friday into
Saturday. A few showers possible across far SW portions of the tri-
state as weak shortwave energy drops south and before moisture/weak
elevated instability depart. Main story will be a cooler and drier
Canadian maritime airmass advecting into the region for Friday and Sat.

Although humidity levels should be in the 50s...gusty east winds on
Friday may pose a enhanced concern for spread of brush fires due to
400-500 kbdi values and available fine fuels. Along the
coast...potential exists for a high rip current risk Friday after into
Sat due to easterly winds and wind waves. Highs should run near
seasonable...upper 70s/lower 80s.

Dry and very warm to hot conditions are expected through early next
week as high pressure sinks southeast of the region and merges with Bermuda
high. A steady moderation in heat and humidity is likely sun through
Wednesday...with highs increasing to 5 to 10 degrees above seasonable
through the early week period.

&&

Aviation /00z Thursday through Monday/...
a surface trough moves across late tonight into Thursday with
another cold front from the north moving in late in the taf
period. VFR into this evening but conditions will lower to
MVFR/IFR in fog late tonight at outlying terminals once again.
Timing could be off by 1-2 hours compared to forecast.

S winds generally between 5-10 knots become light and variable
tonight. Wind speeds remain below 5 feet into Thursday with sea
breezes likely during the late morning/afternoon.

There will be a chance of showers and thunderstorms late afternoon
through the evening on Thursday associated with the approaching
cold front. Probability too low to include in taf as there is
uncertainty on the timing and location of any showers or
thunderstorms.

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: fog possible overnight into Thursday morning
with MVFR visibilities. Sea breeze timing Thursday could be 1-2 hours
off from forecast.

Klga fcster comments: fog possible overnight into Thursday morning
with MVFR visibilities. Sea breeze timing Thursday could be 1-2 hours
off from forecast.

Kewr fcster comments: fog possible overnight into Thursday morning
with MVFR visibilities. Sea breeze timing Thursday could be 1-2 hours
off from forecast.

Kteb fcster comments: fog timing could be off by 1-2 hours.

Khpn fcster comments: fog timing could be off by 2-3 hours. Below
IFR conditions possible.

Kisp fcster comments: fog timing could be off by 2-3 hours. Below
IFR conditions possible.

Outlook for 00z Friday through Monday...
Thursday night...MVFR or below possible with a chance of
showers/thunderstorms.
Friday..chance of MVFR stratus early Friday morning. Otherwise...VFR.
East-northeast winds g15-20kt.
Saturday-Monday...VFR.

&&

Marine...
a weak surface pressure gradient remains across the waters tonight
into Thursday as a trough remain across the New England coast into
northern Jersey. A cold front approaches from the north and moves
across the waters Thursday night. As high pressure builds to the
north late Thursday night the pressure gradient does increase toward
Friday morning. Wind and seas remain below Small Craft Advisory
levels tonight through Thursday night. However...wind gusts may
approach small craft levels toward Friday morning across the eastern
Long Island Sound...eastern Long Island bays...and the ocean waters
east of Moriches Inlet.

Small Craft Advisory level winds and seas are likely on the ocean
Friday following the passage of a cold front. Potential exists for
easterly winds of 15 to 20 knots with gust 25 knots and ocean seas
building to 5 to 6 feet. Small Craft Advisory gusts possible on Li sound and
nearshore waters.

Winds and seas should gradually subside Friday night into Sat...with
sub Small Craft Advisory conds likely Sat night through early next week.

&&

Hydrology...
dry tonight through middle afternoon Thursday. Light precipitation
is possible by late Thursday into Thursday night with one to two
tenths of an inch of rainfall.

No widespread significant rainfall is forecast Friday through the
middle of next week. Drought will continue to develop region wide.
Long Island and southern CT are currently experiencing moderate
drought conditions.

&&

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

&&

$$
Synopsis...met/NV
near term...met/dw
short term...met
long term...Nevada
aviation...jm
marine...met/NV
hydrology...met/NV

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