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Area forecast discussion 
National Weather Service New York New York
1056 am EDT Wednesday Sep 17 2014

Synopsis...
high pressure remains over the region through Saturday. Low pressure
will then track from the Great Lakes through southeast Canada Saturday
night and Sunday with a cold front moving into the area Sunday
night and possibly lingering through Monday. High pressure builds
back in for Tuesday.

&&

Near term /until 6 PM this evening/...
high pressure over the area with strong subsidence keeping are
cloud free. Maybe a few fair weather cumulus popping up this
afternoon over the western zones as some moisture advects in below
an inversion near 800-750 mb. Raised dew points several degrees
inland as dew points have been climbing slowly as moisture moves
into the region. Wind/thermal/moisture profiles in the boundary
layer should allow for sea breezes to develop this afternoon. A
mav/NAM MOS blend looked good for high temperatures.

There is a moderate risk of rip current development at the Atlantic
beaches on today. This may increase to a high risk late in the day
due to swells from tropical cyclone Edouard...situated well out to
sea.

&&

Short term /6 PM this evening through Thursday night/...
high pressure remains the dominant feature in the pattern during
this period. At the same time...the flow aloft amplifies with a middle
level shortwave passing through during Thursday afternoon/evening.
Surface reflection in the form of a cold front/trough passes
through at the same time. Looks like moisture will be too limited
for any chance of showers. 00z GFS has even backed off on quantitative precipitation forecast output
with the passage of these features as compared to its previous few
runs. Will continue with a dry forecast tonight through Thursday night.

Temperatures through the period are a mav/NAM MOS blend...although
weighted more towards the cooler mav guidance for highs on Thursday.
Low temperatures across some the northwest suburbs drop into the lower 40s
Thursday night.

&&

Long term /Friday through Tuesday/...
models are in decent agreement with the overall 500 mb flow through the
long term...although there are timing and amplitude differences
apparent through the entire period. The northern branch of the jet
stream will start off over southern Canada...but as a cutoff low tracks
into the Gulf of Alaska on Sat...the flow will amplify downstream
resulting in ridging over the SW Canada/pacnw and a digging trough
in southeast Canada/the Great Lakes region. This trough will persist over
the eastern US through early next week.

At the surface...high pressure over northern New England Friday morning will
track offshore Friday night and Sat. Dry weather will persist through
this time. As the aforementioned trough digs over the Great Lakes on
Sat...surface low pressure will develop and track through southeast Canada Sat
night and sun. This features warm front will pass by to the north on
sun...followed by its cold front Sun night into Monday morning. The
biggest change with this since yesterday is the decrease in the
amount of rainfall forecast with it. Therefore...have lowered probability of precipitation a
tad. A big difference between the operations GFS and ec is that the
00z ec has the front getting hung up over the area on Monday with a
wave of low pressure developing on it. The upper flow does become
parallel to the front in both models and this is a possibility but
would like to see this solution for a few model runs before committing.
High pressure then builds back in for Tuesday.

Temperatures will vary over the period...Fri...Mon night...Tuesday and
Tuesday night all below normal while the remainder of the period will be
near to above normal.

&&

Aviation /15z Wednesday through Sunday/...
high pressure through the taf period will keep VFR conditions in
place. Few-scattered cumulus development through today. Sea breezes will
be likely with north winds of 5-10 knots becoming more southerly this
afternoon. There is some uncertainty of a few hours with this
timing. Winds lighten again tonight. Overall...high confidence
category forecast and moderate confidence with winds.

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: wind direction could become quite variable
before the sea breeze...which itself could be off by 1-2 hours.

Klga fcster comments: wind direction could become quite variable
before the sea breeze...which itself could be off by 2-3 hours.

Kewr fcster comments: wind direction could become quite variable
before the sea breeze...which itself could be off by 2-3 hours.

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

Kteb fcster comments: wind direction could become quite variable
before the sea breeze...which itself could be off by 2-3 hours.

Khpn fcster comments: wind direction could become quite variable
before the sea breeze...which itself could be off by 1-2 hours.

Kisp fcster comments: wind direction could become quite variable
before the sea breeze...which itself could be off by 2-3 hours.

Outlook for 12z Thursday through Sunday...
Thursday-Sunday...VFR.

&&

Marine...
forecast wind and seas on track with no changes at this time.

Winds will be on the lighter side today through early Thursday
evening with a weak pressure gradient over the area. A cold front
then moves through later in the night with wind gusts approaching
25 knots...but probably falling just short of it. Aside from
this...seas on the ocean will continue to build today and Thursday
due to swells from Edouard. Wavewatch is running about 2 feet too
high...with the nah model performing much better so far. Nah
briefly builds seas up to 5 feet on the ocean late tonight/early
Thursday morning. Since it is a marginal event that would appear to
last for only a short time...will hold off on issuing a Small Craft Advisory at
this time.

A moderate NE flow Friday is expected to cause marginal Small Craft Advisory seas to
continue on the ocean waters Friday/Friday night. Gusts will be
diminishing Friday morning. Sub-advsy conds are then expected through
the remainder of the forecast period.

&&

Hydrology...
no rainfall is expected through the first half of the weekend.

&&

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

&&

$$
Synopsis...jc/24
near term...jc/24/met
short term...jc
long term...24
aviation...jm/pw
marine...jc/24/met
hydrology...jc/24

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