Area Forecast Discussion
Issued by NWS Upton, NY

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668
FXUS61 KOKX 272232
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
632 PM EDT FRI MAY 27 2016

.SYNOPSIS...
Bermuda High pressure will remain across the region through the
weekend. A cold front will pass through the area Monday into
Tuesday. High pressure returns for the middle of the week.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
Convection has fired well nw. Will need to keep an eye on western
zones, west of the Hudson, for possible shower and thunderstorm
development early. HRRR continues to develop convection, along
the seabreeze boundary. Will seabreeze boundary be enough to
break the cap. With increasing cape as the afternoon progresses,
coverage increases warranting chance pops.

The forecast remains on track.

Shortwaves moving through today are progged to be weaker than they
were 24 hours ago. No changes to temps at this time. 850 mb temps
and sea breeze progress should be close to those of yesterday, but
yesterday featured a mostly sunny sky for most of the day for most
locations. Will forecast high temps lower than what occurred
yesterday. Looks like clouds will be more numerous and more opaque
this time around. Have gone above a guidance blend for high
temps, especially across Long Island where guidance has been too
low during the past couple of days.

There is a moderate risk of rip current development at the Atlantic
beaches Today into this evening.

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
An evening shower/thunderstorm is possible northwest of the city,
then with the loss of instability and only weak lift, dry
overnight.

For Saturday, still no significant source of lift outside of weak
mid level shortwaves, but SBCAPEs will be building once again away
from sea breezes. Again, will go with only slight chance to
chance pops, focused more toward the afternoon and away from areas
cooled by sea breezes.

Highs on Saturday should be warmer than on Friday with warmer temps
at the top of the mixed layer, and probably less cloud cover
overall. Again, needed to adjust a guidance blend upward to account
for the low bias as of late, especially over Long Island.

There is a moderate risk of rip currents at the Atlantic ocean
beaches on Saturday.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
Models are in good agreement with the H5 pattern across North
America to start...however timing and amplitude differences start
to become apparent by the middle of the week and even more so by
weeks end.

Sub-tropical ridge over the western atlantic begins to
break down and shift e during the latter part of the weekend but
should still have enough of an influence on the area to keep any
convection associated with an approaching back door cold front
mainly to the north...although it may be close enough for some
storms across the interior...so have maintained the low chc pops
there.

Moisture from a tropical disturbance off the Carolina coast is
forecast to feed up the east coast along a pre-frontal trough
Sunday night and Monday as a cold front approaches from the west.
There is the potential for heavy rainfall with this system as a
plume of tropical moisture surges northward ahead of the
aforementioned system near the SE coast. These values are close
to the maximum observed precipitable water for May 30 per SPC
Sounding Climatology. An approaching shortwave in the northern
branch and sfc cold front will shift this activity to the east
Monday night.

Deep layered ridging then returns through the rest of the week
with the return to summer-like temperatures.

&&

.AVIATION /22Z FRIDAY THROUGH WEDNESDAY/...
The area will remain on the western side of the Bermuda High into
Saturday with a thermal trough across then interior each afternoon.

Convection has largely dissipated across the area. Additional
activity moving into NE PA is likely to dissipate before reaching
the Lower Hudson Valley later this evening.

The main feature of focus this evening is the low-level coastal
jet impacting KJFK and KLGA with gusts up to 25 kt which
developed over the last couple of hours. This feature typically
weakens gradually in the evening while spreading east. KISP may
see a brief period of gusts to around 20 kt.

Winds veer to the SW at under 10kt this evening and then
gradually strengthen to 10-15 kt Saturday. Potential for coastal
low-level jet to redevelop and impact KJFK and KLGA Saturday
afternoon.

     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: Occasional gusts 25 kt early this evening with
coastal seabreeze jet.

KLGA TAF Comments: Occasional gusts 20-25 kt early this evening
with coastal seabreeze jet.

KEWR TAF Comments: Timing of winds veering back to S/SW this
evening may be delayed by 1-2 hours.

KTEB TAF Comments: Timing of winds veering back to S/SW this
evening may be delayed by 1-2 hours.

KHPN TAF Comments: Low chance of early evening shower/thunderstorm.

KISP TAF Comments: Occasional gusts to around 20 kt early this
evening.

.OUTLOOK FOR 18Z Saturday through Wednesday...
.Saturday afternoon-Sunday...Mainly VFR with afternoon
seabreezes. There is a chance of MVFR or lower in any isolated to
scattered afternoon/evening showers/thunderstorms; mainly to the
n/w of NYC.
.Sunday night-Monday...MVFR or lower probable with showers and
thunderstorms.
.Monday night-Tuesday...Becoming VFR Monday night. Seabreezes
likely Tuesday afternoon.

&&

.MARINE...
The western periphery of Bermuda high pressure remains across the
waters through Saturday. Winds and seas are expected to remain below
small craft levels during this period, however, late this afternoon
into early evening there could be occasional gusts to 25 kt over
the ocean waters west of Fire Island Inlet. Will also be watching
seas as they build close to 5 feet across the outer waters.

A weak pressure gradient across the waters will then keep winds
and seas below sca levels through Tuesday.

&&

.HYDROLOGY...
Isolated to scattered thunderstorms are possible mostly for the
inland areas this afternoon, this evening, and Saturday
afternoon. However, no significant widespread precipitation is
expected through the weekend.

Rainfall amounts around one half to three quarters of an inch are
possible on Monday with locally higher amounts. Localized urban or
poor drainage flooding is possible from the heaviest rain.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...None.

&&

$$

SYNOPSIS...24/PW
NEAR TERM...PW
SHORT TERM...PW
LONG TERM...24
AVIATION...DW
MARINE...24/PW
HYDROLOGY...24/PW



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