Area Forecast Discussion
Issued by NWS Upton, NY

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FXUS61 KOKX 230805

Area Forecast Discussion
National Weather Service New York NY
405 AM EDT MON MAY 23 2016

Low pressure off the North Carolina coast moves slowly north today
and tonight, then drifts northeast Tuesday and Tuesday night,
remaining offshore and passing south and east of the
region. High pressure will then briefly follow for Wednesday and
Thursday morning with a cold front stalling in the vicinity
Thursday afternoon or night. The front returns north as a warm
front on Friday.


A weak surface coastal low, 1005 mb, will move slowly north today
as a mid and upper cutoff low drifts along the mid Atlantic coast.
This low and associated cold pool will have vort maxes rotating
around the cutoff low. In addition a weak surface trough will be
developing along the coast. Initial clearing will allow for
daytime heating and surface based instability to increase. Both
the surface trough and upper low will provide convergence and lift
for scattered showers to develop. And with the instability and
cape increasing to 200 to 400 j/kg this afternoon, isolated
thunderstorms will be possible.


The surface low continues to drift north and northeast tonight
through Tuesday night, remaining offshore, as the mid and upper
cutoff low also drifts along the coast. With the low a little
closer to the coast tonight and additional energy rotating
through, there will be a better, likely, chance of showers. There
may be isolated thunder early, however, cape and instability will
be decreasing. Not all areas will see precipitation, and will be
dependent on where the low and upper low drift.

Once again, Tuesday afternoon thunderstorms will be possible as a
surface trough develops and the low drifts east of the region.
Precipitation ends during Tuesday evening as the upper low begins
to fill and open, moving farther to the east, and height will be
rising at all levels after 03z Wednesday. Could be a rather sharp
end to the precipitation.


Ridging aloft on Wednesday will help slow down a cold front sinking
south across the Northeast. Insufficient moisture and lift should
therefore keep the cwa dry. Mixing to 850 mb, where temps are
forecast to rise to around 13C, along with a mostly sunny sky and SW
winds will bring high temps about 10-15 degrees above normal across
the entire area.

The cold front weakens and stalls over us on Thursday as ridging
aloft continues. Chance of afternoon tstms from around the city and
points west where better instability will reside. Subsidence will
limit mixing more than on Wednesday, so expecting high temps to be a
couple of degrees cooler on average versus Wednesday.

Friday and Saturday look to be similar days with ridging aloft and a
weak SE-S wind flow. This will probably limit chances of
showers/thunderstorms to inland sections both days, and chances
don`t appear to be very high due to limited moisture and/or capping
from ridging aloft. Models however hint at the possibility of an MCS
moving through late Thursday night into early Friday morning, so a
more widespread rainfall is still a possibility. High temps both
days still averaging above normals in spite of a limited mixing

It appears that Sunday could feature deeper mixing,and along with
rising temps aloft, high temps could end up a few degrees warmer
than currently forecast. Didn`t want to stray too far from WPC
guidance this far out in time, which is warmer than superblend.
Highs well into the 80s for some inland spots. Once again, limited
chances of showers/storms focused inland.


Weak high pres remains over the area as low pres remains nearly
stationary off the Delmarva into Tue.

A lot of variability in the flow thru the taf period. Nearly calm
this mrng then ne flow attempts to develop. Sea breeze flow then
expected to take over by early aftn. Wind direction will become
vrb tngt as the sea breeze circulation weakens.

Mainly vfr...however some areas of br will likely result in
pockets of mvfr or lower this mrng. Most favorable areas away from
the city arpts.

.OUTLOOK FOR 06Z Tuesday through Friday...
.Late Monday night...mvfr or lower in -ra.
.Tuesday...period of mvfr in -shra.
.Thursday night...low chc of mvfr -shra.
.Friday...mvfr possible in tstms.


Small craft seas remain on the ocean waters this morning, mainly
from swells from departing low pressure that was meandering near
Nova Scotia. Seas are expected to fall below 5 feet by late this
morning. The general small craft hazard was converted to a small
craft for hazardous seas and runs through 11 am this morning.

Otherwise, a rather weak pressure gradient force will be across
the waters today through Tuesday night as a weak low off the North
Carolina coast moves north today and tonight, and northeast
Tuesday and Tuesday night. Winds will remain below small craft
levels today through Tuesday night. And seas on the ocean waters
will remain below small craft once the seas subside this morning.

Sub-sca conditions will prevail for the rest of the forecast period
with the lack of a strong pressure gradient or significant swell.


A long periods of generally light precipitation is expected today
through Tuesday evening with 1/2 to 3/4 of an inch expected.
Locally higher amounts are possible if any thunderstorms develop
this afternoon and Tuesday afternoon.

Widespread significant rainfall is not expected for the rest of the


MARINE...Small Craft Advisory for hazardous seas until 11 AM EDT this
     morning for ANZ350-353-355.


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