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Area forecast discussion 
National Weather Service New York New York
453 am EDT Wednesday Oct 1 2014

Synopsis...
an upper level disturbance will remain over the region through
Thursday while high pressure builds in at the surface to end the
week. A cold front will pass on Saturday...followed by potentially
another frontal system for the beginning of next week.

&&

Near term /until 6 PM this evening/...
light rain noted over southeast CT and far eastern Li early this morning as
weak vorticity maximum continues to progress to the north and east and a
persistent northeasterly surface flow keeps the lower levels very moist. At
the moment...the County Warning Area remains devoid of any fog development.
However...it is possible for some patchy fog formation over interior
CT/New York near daybreak so have included in the forecast.

Attention for the day remains focused on the progression of a closed
upper level low currently noted on water vapor imagery over western
PA. General consensus amongst the 00z model solutions is for the low
to trek across the area during the day...lingering though until
Thursday. NE flow keeps the lower levels very moist...so despite the
lack of any real surface lift...strong forcing aloft should work to
produce scattered-num showers. Embedded within the showers is the
possibility for moderate to even heavy rainfall...which the
mesoscale models continue to suggest will occur over eastern Long Island
and southeast CT...corresponding to the most likely location of the
strongest forcing/vorticity maximum by this aftn/evening. So for probability of precipitation...am
keeping likely wording in for areas generally east of NYC
metropolitan...with chance to the west.

A mix of cloud cover...precipitation and NE flow will result in temperatures resting
right around normal for highs today.

&&

Short term /6 PM this evening through 6 PM Thursday/...
precipitation continues this evening...with the main question on the ending
time. Upper level low pivots east...with the main forcing generally
residing over eastern areas of the County Warning Area for the night. As
such...began to taper probability of precipitation back for the first half of the
night...with dry conditions even possible by 06z west of NYC.
Confidence rests with the precipitation continuing though over eastern Li/southeast
CT. However...with the bulls eye of main forcing mainly
offshore...siding more with precipitation being on the lighter side. 00z NAM
and European model (ecmwf) do suggest the potential for some heavier showers over the
far eastern reaches of the County Warning Area...but will want to see the trend for
the day before siding with the heavier amts. Light precipitation lingers just
offshore then during the day Thursday...tapering off late in the day
as the upper level low finally exits the region...being replaced
with ridging aloft.

&&

Long term /Thursday night through Tuesday/...
high pressure will keep the area dry through Friday evening. The cold front passage
and associated rainfall are still lined up for late Friday night into
Sat. The 00z GFS and European model (ecmwf) continue to support this timing. Pop has
been increased to Cat for Sat...and likely pop also continues into
early Sat evening across southern CT and Long Island.

Sunday will be dry as all of the moisture will be shunted off to the
east. Then rain chances should return for the beginning of next week
with an upper trough approaching...mainly Monday into Monday night.

For highs...both Friday/Sat should see upper 60s/lower 70s...then a
cooler day on Sunday with only Lower/Middle 60s. Slight moderation
expected ahead of the next upper trough...mainly 65-70. Lows Sat
night and Sunday night do not look to be cold enough for
frost concerns.

&&

Aviation /09z Wednesday through Sunday/...
an upper level low passes over the region over the area today as a
very moist low level NE flow prevails at the surface. This results
in marginal VFR conditions through the taf forecast period...though
areas of IFR are likely this morning.

Light rain with a few embedded showers and localized thunderstorms and rain possible for
eastern sections into this evening.

High confidence in the persistent north-northeast surface flow through the period.
Occasional gusts into the upper teens for the New York metropolitan expected this
afternoon though not included in the tafs.

... 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: unable-forecast fluctuations in ceiling category
expect through the period...though moderate confidence in VFR for
the afternoon.

High confidence in wind forecast.

Klga fcster comments: unable-forecast fluctuations in ceiling category
expect through the period...though moderate confidence in VFR for
the afternoon.

High confidence in wind forecast though direction may swing right of
040 magnetic at times.

Kewr fcster comments: unable-forecast fluctuations in ceiling category
expect through the period...though moderate confidence in VFR for
the afternoon.

High confidence in wind forecast.

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

Kteb fcster comments: unable-forecast fluctuations in ceiling category
expect through the period...though moderate confidence in VFR for
the afternoon.

High confidence in wind forecast.

Khpn fcster comments: unable-forecast fluctuations in ceiling category
expect through the period...though moderate confidence in VFR for
the afternoon.



Kisp fcster comments: unable-forecast fluctuations in ceiling category
expect through the period.

Outlook for 06z Thursday through Sunday...
early Thursday morning...MVFR to IFR ceilings/visibilities in -ra. East-NE winds
10-15 knots...with g 20 knots along the coast.
Thursday...becoming VFR. NE winds around 10 knots.
Friday...VFR. Southeast-S winds around 10 knots.
Sat...rain likely - MVFR or lower at times. Southeast wind 10-15g20 knots.
Sun...VFR.

&&

Marine...
Small Craft Advisory conditions on the ocean waters today through tonight with
increasing NE flow. Gusts up to 25 kts will be possible later this
afternoon...while seas generally between 5 and 7 feet are expected. On
the non ocean waters...sub-sca conditions today. Could see occasional
gusts up to 25 kts in the bays around Long Island and eastern Long
Island Sound...with the potential to become more persistent
tonight. As such...a Small Craft Advisory might need to be issued for these waters
tonight/Thursday. The remaining waters should remain below Small Craft Advisory
criteria through Thursday. Have extended the Small Craft Advisory for the eastern
two-thirds of the ocean waters until Thursday evening...while the
Small Craft Advisory continues for the western portions just through tonight.

For Thursday night and beyond...hazardous ocean seas are likely to
continue from Thursday night into Friday morning...they should fall blw 5 feet
late Friday into Friday night...and once again ramp up through the weekend.
Elsewhere...the eastern sound/bays could see Small Craft Advisory conds in Post-frontal west
flow on Sunday. Small Craft Advisory conds are possible all waters again on Monday ahead
of the next system.

&&

Hydrology...
no significant rainfall resulting in hydrologic issues is currently
expected through the forecast period.

Rainfall totals today across Long Island and Connecticut will
range from a quarter of an inch to three-quarters of an inch.
Areas to the west will generally be a quarter of an inch or less.

Quantitative precipitation forecast of 3/4 to 1 inch likely northwest of NYC on Sat with cold front...and
1/2 to 3/4 inch farther east.

&&

Okx watches/warnings/advisories...
CT...none.
New York...none.
New Jersey...none.
Marine...Small Craft Advisory until 6 am EDT Thursday for anz355.
Small Craft Advisory until 6 PM EDT Thursday for anz350-353.

&&

$$
Synopsis...Goodman/Sears
near term...Sears
short term...Sears
long term...Goodman
aviation...tongue
marine...Goodman/Sears
hydrology...Goodman/Sears

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