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Area forecast discussion 
National Weather Service New York New York
956 am EDT Friday Apr 18 2014

high pressure retreats to the northeast today...with another area of
high pressure building down from southern Canada through the
weekend. The high then slowly slides to the east into Tuesday. A
frontal system will impact the area from Tuesday into Wednesday.
High pressure then builds down from south central Canada into


Near term /until 6 PM this evening/...
forecast remains on track this morning. Patchy to areas of frost
still lingering over portions of the tri state area outside of NYC
metropolitan so will maintain the frost advisory as is until 9 am.

Generally dry weather today with high pressure slowly pushing to the
northeast as a weakening front approaches from the north and west.
General model consensus has trended in keeping the front to the
north...with no precipitation expected to impact the area as the main
northern stream energy remains over northern New England as well.
Latest infrared satellite imagery indicates an area of stratus having
pushed into New Jersey and southern NYC/Long Island...and is
expected to persist through the morning with the northeast flow. As
the winds come around to the south...should see the low level clouds
begin to scatter out but a passing vorticity maximum will keep the increased
sky coverage...increasing the middle and high level clouds for the
remainder of the afternoon. Despite a warming trend with warm air advection...the
combination of the northeast flow...and cloud cover will help to
keep temperatures still almost 10 degrees below normal.


Short term /6 PM this evening through 6 PM Saturday/...
surface high retreats to the northeast by tonight...with a weak
trough setting up briefly over New England. The trough is quickly
replaced by the next high pressure...building south and east from
Canada. Upper level trough swings through tonight but again main
forcing is to the north and with little to no forcing at the surface
along with minimal moisture...should see a dry night. Ridging sets
up quickly behind the departing trough for Saturday and with
building subsidence...Saturday looks to be a dry and sunny day once
the morning clouds scatter out. Temperatures expected to rebound
back to near normal for tonight...and then even a few degrees above
normal on Saturday with downsloping influence.

Increased winds and low relative humidity values on Saturday could lead to an
enhanced risk of fire spread. Northwest winds will increase...with
sustained 10-15 miles per hour...and gusts up to 20 miles per hour during the
afternoon...corresponding with relative humidity values dropping to around 30


Long term /Saturday night through Thursday/...
a northern stream ridge builds over the area Saturday night and
Sunday...then slides to the northeast Sunday night. Associated
subsidence should keep the area dry and with minimal cloud cover in
this time frame. For lows Saturday night used a blend of mav/met
guidance...with values near normal in NYC proper...and a few degrees
below normal elsewhere. For highs Sunday used a blend of mixing down
from 925-875 hpa per BUFKIT soundings...with NAM 2-meter
temperatures and a blend of mav/met guidance. Expect readings to be
slightly below normal. For lows Sunday night used a blend of NAM
2-meter temperatures with a blend of mex/men/ekd/ece/ecm/wpc
guidance...with values a few degrees below normal.

Another northern stream ridge builds over the area Monday...then
exits to the northeast Monday night. Associated subsidence will keep
things dry...but could see an increase in mainly middle to high clouds
by late Monday night ahead of an approaching developing full
latitude trough.

Trough continues to sharpen as it slowly moves east into the western
Appalachians on Tuesday...with any precipitation ahead of it likely
confined to the northwest 1/3-1/2 of the County Warning Area. As the trough moves into east
PA/upstate New York Tuesday night...and begins to take on a bit of a
negative tilt...would expect widespread showers across the County Warning Area
Tuesday night. However...noting some differences in model
timing...and inherent uncertainty this far out...have capped probability of precipitation at
chance at this time.

Some uncertainty as to how quickly the precipitation exits to the east
on Wednesday...though the 00z European model (ecmwf) has come closer to the 00z CMC
and GFS when compared to the 12z European model (ecmwf). Main question is how soon
will a cutoff low develop as the trough continues to negatively tilt
as it lifts northeast...and how quickly will this cutoff lift to the
NE. For now...have leaned towards the slightly slower European model (ecmwf) slower is often the better forecast with negatively
tilted systems. As a result do have slight chance probability of precipitation over most of
the area Wednesday morning...and the NE 1/3 of the County Warning Area Wednesday

A deep layered ridge begins to build in from the Midwest Wednesday
night and have gone with a dry forecast for now.
However...with a developing cutoff low forecast to be not to far to
the NE...cannot completely rule out that the forecast could later
evolve into a cloudier one with isolated-scattered showers in this time

For temperatures Monday-Thursday used a blend of
mex/men/ekd/ece/ecm/wpc guidance. Temperatures should run near
normal on Monday...above normal on Tuesday...with the possibility of
some areas mainly from NYC on west hitting 70. Wednesday and Thursday
for now should see temperatures within a few degrees on either side
of normal. However...if the aforementioned cutoff low ends up closer
to the area...then below normal temperatures would be possible.


Aviation /14z Friday through Tuesday/...
high pressure centered over the Canadian Maritimes and extending
down the eastern Seaboard will slowly move east while weakening

MVFR stratus struggling to scour will keep in the taf until
18z or so.

East flow continues through the day...but local sea breezes this
afternoon will turn winds S/southeast at 8-12 knots. Winds diminish to 5 knots or
less tonight.

Low confidence as to whether or not stratus will redevelop after 00z will leave out of the tafs for now.

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: ceilings bkn020-025 through 18z.

Klga fcster comments: ceilings bkn020-025 through 18z.

Kewr fcster comments: ceilings bkn020-025 through 18z.

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

Kteb fcster comments: occasional ceilings bkn025 through 18z.

Khpn fcster comments: potential for broken ceilings 2000-2500 feet through

Kisp fcster comments: ceilings bkn015-020 through 18z.

Outlook for 12z Saturday through Tuesday...
Saturday-Monday night...VFR.
Tuesday/Tuesday night...MVFR possible with showers...cold frontal passage.


winds and seas remain on track as forecasted this morning. Small Craft Advisory
for hazardous seas remains in effect through 06z with guidance
keeping the seas above 5 feet through this evening. Elsewhere...sub-
Small Craft Advisory conditions expected through Saturday. Once the seas on the
ocean subside tonight...sub-sca conditions expected there as well.

At this time...sub-sca conditions are forecast from Saturday
night-Tuesday...with winds on non-ocean waters 10 knots or less.
However...there is a chance that the coastal ocean waters could
experience wind gusts to around 25 knots late Saturday night and
Sunday. Otherwise winds on the coastal ocean waters should also be
10 knots or less until late Tuesday.


no significant precipitation is expected through the weekend.

There is the potential for a significant rainfall from late Tuesday
into Wednesday morning. At this time...there is too much uncertainty
to specify exact amounts or any potential impacts - if any.

Note...minor flooding continues along the Connecticut River. For
additional information...please refer to the latest flood warnings
from National Weather Service Taunton Massachusetts.


Okx watches/warnings/advisories...
New York...none.
New Jersey...none.
Marine...Small Craft Advisory for hazardous seas until 2 am EDT
Saturday for anz350-353-355.


near term...Sears
short term...Sears
long term...maloit
fire weather...