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Area forecast discussion 
National Weather Service New York New York
740 PM EDT Wednesday may 6 2015

Synopsis...
high pressure builds in tonight and Thursday...then eventually
moves into the western Atlantic Ocean this weekend. Meanwhile...
low pressure will drift from the southeast coast into the middle-
Atlantic...where it will meander until a cold front moves through
the region and pushes it out to sea next week.

&&

Near term /until 6 am Thursday morning/...
dewpoints and temperatures were running a few degrees lower than
forecast. The forecast database was adjusted for this and the
trend was followed for the remaining temperatures tonight...lowering
min temperatures a few degrees as well. Cloud coverage was slightly
adjusted as well. Otherwise...rest of forecast on track.

Ridging at the surface and aloft tonight will dry out the
atmospheric column. Expect diminishing cloud cover tonight as
drier air filers in from the north. This will promote radiational
cooling overnight along with light to calm winds. Overall...min
temperatures forecast are slightly below the relatively cooler of MOS
guidance.

&&

Short term /6 am Thursday morning through Thursday night/...
deep layered ridging continues on Thursday. Associated subsidence
helps keep low relative humidity aloft...bringing US a sunny day...but also limits
the mixing layer somewhat. The mixing layer depth will be further
reduced by sea breezes that are likely to develop due to a light low
level synoptic flow. Based on temperatures at the top of this layer...a
mav/NAM MOS blend looked good for high temperatures...which will be above
normals.

Dry weather continues into Thursday night. Low temperatures not as cool as
tonight's.

&&

Long term /Friday through Wednesday/...
surface high pressure over the northeast will move offshore on Friday and
remain offshore through the weekend. With upper level ridging along
the northeast...can expect a prolonged period of SW flow with
unseasonably warm temperatures through the weekend.

Low pressure will meander off the southeast U.S. Coast through the
weekend and then slowly drift to the north early in the new week.
There are differences between the GFS and the European model (ecmwf) in terms of
where the low will go...but the high over the western Atlantic and
the upper ridge over the northeast should keep the low too far to
the south to dramatically impact the weather in the local area.
Depending on where the low GOES...could have some light rain
spreading north and into southern zones early in the new week.

In addition...low pressure over the Great Plains states will slowly
track to the east over the weekend...making it through the Ohio
Valley and into western New York/PA by Tuesday morning. As this system
presses to the east...chances for showers/thunderstorms will increase
beginning Sunday night and Monday...and the highest probability of precipitation will occur
Tuesday-Tuesday night as the system works its way across the region.
High pressure builds into the Ohio Valley on Wednesday.

With SW flow across the region and increased low level moisture...
can expect patchy fog to develop Friday night and Saturday night...
and that fog will dissipate late in the morning.

Deep SW flow will also result in above normal temperatures through the
start of the new week with highs generally in the upper 70s to low
80s across NYC/northeast New Jersey/lower Hudson Valley/parts of interior
portions of southern CT. Highs across Long Island and coastal CT
will be in the middle to upper 70s as flow comes off the colder waters.
Highs will be in the upper 60s to around 70 along the coast.

Afternoon sea breezes are likely Friday through Sunday...resulting
in cooler temperatures each afternoon.

Temperatures will be a few degrees cooler on Tuesday with abundant cloud
cover on Tuesday as the frontal system moves through the region.
More seasonal airmass returns to the area on Wednesday with near
normal temperatures.

&&

Aviation /00z Thursday through Monday/...
high pressure remains over the area tonight into Thursday
morning...then moves east of the area Thursday afternoon.

Unlimited ceilings and visibilities through the taf period.

Wind becomes light and variable to near calm early this
evening...then southerly...160 to 200 true...5 knots to 10 knots Thursday
morning.



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: after 18z southerly wind may be stronger...15
to 20 knots with sea breeze enhancement.

Klga fcster comments: a developing northeast flow 5 to 10 knots
Thursday morning may persist a couple of hours past 17z before
becoming southerly...as a sea breeze moves through. Moderate
confidence in the wind forecast.

Kewr fcster comments: low chance wind will become more
southeast...150 true...Thursday afternoon with a sea breeze moving
through...probably after 19z.

Kteb fcster comments: low chance wind will become more
southeast...150 true...Thursday afternoon with a sea breeze moving
through...probably after 19z.

Khpn fcster comments: no unscheduled amendments expected.

Kisp fcster comments: after 19z southerly wind may be
stronger...up to 15 knots...with sea breeze enhancement.

Outlook for 00z Friday through Monday...
Thursday night-Friday...VFR.
Saturday-Monday...potential for IFR or lower in stratus and/or
fog at night and the morning. Otherwise VFR.

&&

Marine...
seas and wind forecast on the waters mainly on track this
evening.

With high pressure over the area waters...there will be a lack of a
tight pressure gradient. This will result in a tranquil period with
light winds and seas of 1 to 2 feet through Thursday night.

Sub-Small Craft Advisory conds will then continue through the weekend and into the
start of the new week. Some near-shore gusts to 20 knots possible
each afternoon due to local sea breezes.

Southerly gradient increases by Tuesday...resulting in at least seas
building to Small Craft Advisory levels.

&&

Hydrology...
no rain is expected through the weekend. The next chance for widespread
rainfall will be Monday through Tuesday as a frontal system moves
through the region.

&&

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

&&

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

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