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fxus61 kokx 171057 
afdokx

Area forecast discussion
National Weather Service New York New York
657 am EDT Tue Oct 17 2017

Synopsis...
a broad area of high pressure builds in from the west today,
and will remain in control through the weekend.

&&

Near term /until 6 PM this evening/...
frosty conditions across interior early this
morning...otherwise an upper shortwave axis moves east today,
with slight mean upper troughing in its wake. At the surface,
high pressure to the west gradually builds to the south of the
region. Gusty north winds to start the day will gradually weaken
through the day.

Despite abundant sunshine, another slightly below seasonable day
expected with cold pool overhead. Temps likely only topping out in
the upper 50s to lower 60s.

&&

Short term /6 PM this evening through 6 PM Wednesday/...
slight shortwave upper ridging builds into the region during
this period, while surface high pressure gradually slides south
of the region.

Good radiational cooling conditions likely tonight across
interior with a favorable waa aloft setup for decoupling;
allowing temps to fall into the lower to mid 30s once again.
Frost conditions are likely once again late tonight across the
interior of southern CT and for the suburbs northwest of NYC Metro.
After collab with surrounding offices, will hold off on frost
advisory just yet to see if any interior areas experience a hard
freeze early this morning, ending their growing season. For
city and coast, increasing potential for mixing as the night
wears on in strengthening return flow, which may keep or bounce
temps into the 40s. Lower 50s likely for the NYC Metro.

Sunny skies and a gradual moderation in temps begins on
Wednesday as SW return flow develops around the high to the
south. Temperatures should warm to slightly above seasonable
levels int he upper 60s to lower 70s.

&&

Long term /Wednesday night through Monday/...
ridging both aloft and at the surface prevails through much of
the period. Only a weak and dry cold front passage occurs
Thursday night as the flow aloft turns cyclonic for a short
period. The next chance of rainfall doesn't appear to arrive
until Monday night with the approach of the next cold front.
Expect abundant sunshine throughout the period with daytime
highs averaging around 7-10 degrees above normal.

&&

Aviation /12z Tuesday through Saturday/...
high pressure sets up just southwest of the region through
Wednesday.

VFR through the taf period. Northerly winds will gradually back
through the day. Occasional gusts are possible this morning,
especially between 12 and 16z.



..NY Metro enhanced aviation weather support...

Detailed information...including hourly taf wind component fcsts
can be found at: http:/www.Weather.Gov/zny/n90

Kjfk taf comments: no unscheduled amendments are expected.

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

Klga taf comments: no unscheduled amendments are expected.

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

Kewr taf comments: occasional gusts to around 15kt possible
through 15z.

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

Kteb taf comments: occasional gusts to around 15kt possible
12-15z.

Khpn taf comments: no unscheduled amendments are expected.

Kisp taf comments: occasional gusts to around 15kt possible
12-15z.



Outlook for 12z Wednesday through Saturday...
Wednesday-Saturday...VFR.

&&

Marine...
marginal Small Craft Advisory gusts and seas are limited to the ocean waters
this morning, and will fall below Small Craft Advisory by late morning as the
pressure gradient weakens.

High pressure prevails through the upcoming weekend with sub Small Craft Advisory
conditions. The only exception is that Small Craft Advisory conditions may be
approached Thursday night on the eastern ocean waters ahead of a
weak cold front with SW winds gusting up to 20 kt.

&&

Hydrology...
no hydrologic issues expected through this weekend.

&&

Okx watches/warnings/advisories...
CT...frost advisory until 9 am EDT this morning for ctz005>008.
New York...frost advisory until 9 am EDT this morning for nyz067>070.
New Jersey...frost advisory until 9 am EDT this morning for njz002.
Marine...Small Craft Advisory until 11 am EDT this morning for anz350-
353-355.

&&

$$
Synopsis...jc/NV
near term...Nevada

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