Area Forecast Discussion
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FXUS61 KOKX 241013
Area Forecast Discussion
National Weather Service New York NY
613 AM EDT Sat Sep 24 2016
High pressure builds over the Tri-State from southeast Canada
through Sunday night, then slides offshore on Monday. A cold front
moves through Tuesday with high pressure returning for the
remainder of the week.
.NEAR TERM /THROUGH TONIGHT/...
Just a few showers across southwest LI as of 10z and these will
quickly move offshore. The rest of the morning should be dry so
have removed PoPs after 10z. The cold front continues to move
further south with much drier dew points advecting southward
through the morning. However, enough moisture will persist in the
low levels of the atmosphere to keep nearly overcast conditions
through mid morning, especially from NE NJ and NYC through Long
Island. Clearing should begin to take place across the north
around or just after sunrise. It will also be breezy near the
coast this morning, but winds should generally settle around 10
mph later this morning into the afternoon.
NW flow aloft on the backside of an upper low digging across the
Canadian Maritimes will help scatter out the clouds with just
partly cloudy skies this afternoon. Forecast high temperatures
are in the upper 60s and lower 70s, which are near normal for this
time of year.
There is a high risk for rip current development at ocean beaches
Mostly clear skies tonight with a high pressure beginning to
settle over the area. There will likely be enough of a pressure
gradient for at least light winds, but still think below normal
lows are achievable. Forecast lows are in the lower 40s inland to
the upper 40s to lower 50s closer to the coast.
.SHORT TERM /SUNDAY THROUGH MONDAY/...
Upper low moves out into the north Atlantic Sunday into Monday as
deep upper ridging settles over the northeast. Surface high
pressure will dominate the weather both days.
High temperatures in the upper 60s to near 70 degrees are forecast
both days, with Sunday having the potential to be a few degrees
cooler than Monday. Overall though, these temperatures are close
to seasonable levels.
Excellent radiational cooling conditions are possible Sunday
night. Lows range from the upper 30s and lower 40s inland to lower
and middle 50s in the city. Temperatures could fall a bit lower
than forecast across the interior, and this could bring about a
chance for some frost. For now have left out of the forecast, but
will continue to monitor trends. The best chance of this occurring
as it stands now would be across Orange County.
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
The high moves offshore Monday night as an upper trough cuts off
and digs into the Great Lakes. A cold front will quickly approach
Monday night ahead of the upper low. The latest models have come
into much better agreement with the timing of the cold front as
well as the alignment of the best lift and moisture. Have
therefore increased PoPs to likely late Monday night west and then
translated them eastward Tuesday morning. As the system becomes
vertically stacked over the Great Lakes Tuesday morning, the cold
front will surge eastward through the region. This system should
bring a band of showers through, ending across the east Tuesday
The upper trough/low will remain across the eastern US through the
end of the week, with models differing on how quickly it opens up
and lifts out. However, the atmosphere looks dry under the trough
with the deep moisture well offshore. Surface high pressure will
build in for the rest of the week as the upper trough lingers.
Temperatures for the long term period will be near seasonable
.AVIATION /10Z SATURDAY THROUGH WEDNESDAY/...
Canadian high pressure builds in through the weekend.
Showers, over Long Island and SE CT as of 07Z, will be off shore
by sunrise and MVFR CIGs will scatter by mid morning from north to
south. All areas become VFR by AFTN with a northerly flow.
.Outlook for 06Z Sunday through Wednesday...
.MON NGT...VFR with possible showers developing.
.TUE...Mainly VFR. Chance of showers at times.
.WED...Any showers end. VFR.
The SCA on near shore waters has been allowed to expire as winds
have fallen below 25 kt. A few gusts to 20 kt are still possible
Gusts around 25 kt on the ocean continue through middle morning
before falling closer to 20 kt this afternoon as the gradient
weakens and high pressure builds over the waters.
Ocean seas will continue to build to SCA levels through the
morning. Seas will remain around 5 ft through at least Sunday
morning as residual SE swell from well offshore Tropical Cyclone
Karl. Some uncertainty in how long these swells will linger, so
for now have extended the small craft on the ocean through 18z
Otherwise, sub-sca conditions are forecast through Tuesday. Seas
could build close to 5 ft on the ocean as a frontal boundary
lingers offshore and high pressure builds over the waters.
No significant precipitation is forecast through Monday. A cold
front moves through Tuesday with a good chance of widespread
showers. However, no hydrologic impacts are anticipated.
NY...High Rip Current Risk through this evening for NYZ075-080-081-
MARINE...Small Craft Advisory until 2 PM EDT Sunday for ANZ350-353-355.