Area Forecast Discussion
Issued by NWS Upton, NY
FXUS61 KOKX 250452
Area Forecast Discussion
National Weather Service New York NY
1252 AM EDT WED MAY 25 2016
High pressure builds to the south through Wednesday night. A cold
front moves through on Thursday. High pressure will then dominate
through Saturday night as a series of weak upper level
disturbances move across. A cold front will move through on
Sunday. High pressure will build in its wake across New England
Sunday afternoon and night, then pass offshore Monday, allowing a
broad area of low pressure to begin approaching from the south
later Monday into Tuesday.
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
Measurable precipitation has come to an end, so have removed all
pops greater than 14 from the area for the remainder of the
Main issue overnight will be patchy fog...mainly over coastal CT
and eastern Long Island, as well as possibly portions of the Lower
Hudson Valley. For now, appears will only be locally dense, so
will address with a special weather statement. However, will
continue to monitor, as cannot rule out the dense fog becoming
more widespread and needing to go with a short fused Dense Fog
Advisory for all/part of this area for early this morning.
Ridging aloft builds in overnight, with increasing subsidence
allowing for cloud cover to diminish. Lows were a blend of 1/3
MET, 1/3 MAV and 1/3 12z GMOS...with minor adjustments downward
for normally cooler locations.
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM THURSDAY/...
For Today, ridging aloft continues with high pressure
establishing itself southwest of the region. A very warm day is
expected with highs around 15 degrees above normal on
average...cooler at the immediate eastern shorelines with partial
sea breeze influences. Overall though less marine influence with
the more westerly flow.
For Wednesday Night and Thursday, aloft there will be continued
ridging. At the surface, a cold front moves through by early
Thursday but will be weakening as well.
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
summer like warmth will continue through the first half of the
weekend as longwave upper ridging moves across. Shortwave
disturbances will however be able to move through the longwave
ridge and bring chances for late day convection mainly from NYC
north/west both Friday and Saturday. GFS seems too quick to do so
on Thursday as well, and think any convection that day will be
isolated in nature and confined to well NW of NYC.
High temperatures both Thu/Fri will be well into the 80s in most
places, and some isolated lower 90s are not out of the question
somewhere in urban NE NJ, in the valleys of Orange County, or the
interior lower CT river valley. Lows will range mostly from the
mid 50s to the mid 60s.
The ridge then weakens across New England in response to a sharp
northern stream disturbance moving across eastern Canada, pushing
a back door cold front through on Sunday as a surface high builds
across New England. Forecast details become less certain from
Sunday onward, and will be dependent on how far south the front
sinks. Forecast temperatures could be at least several degrees
cooler and chances for rain lower if the front does push farther
south. Leaning more toward the ECMWF idea of more of a glancing
blow from this cooler air mass for now.
As we go into Monday night and Tuesday, we should start dealing
with influx of Atlantic moisture well north of a subtropical or
tropical weather system now just beginning to organize near and
northeast of the Bahamas, and forecast by global models to head
toward the Southeast coast.
.AVIATION /06Z WEDNESDAY THROUGH SUNDAY/...
Low pressure departs to the northeast as high pressure builds to
the south overnight and Wednesday.
Mid and high clouds give way to clear skies overnight and through
the day Wednesday. However, lingering stratus will take a little
longer to scour out for eastern terminals such as KGON. In
addition, patchy fog will likely develop after midnight for a few
outlying terminals. MVFR or IFR visibilities are possible.
After 12z, any fog lifts.
Winds will be light overnight. West winds 5 to 10 kt in the
morning Wednesday will increase to 9 to 13 kt in the afternoon. A
few gusts are possible in the 15 to 20 kt range.
Winds may back around to the s/sw at KJFK, and CT terminals in
the afternoon with seabreeze influence.
.OUTLOOK FOR 00Z Thursday through Sunday...
.Wednesday night through Thursday...VFR.
.Thursday night through Friday morning...Mainly VFR but sub-VFR
possible in showers/evening thunderstorms.
.Friday-Saturday...MVFR possible in afternoon/evening tstms.
.Sunday...Mainly VFR, but sub-VFR in showers possible NW of NYC.
Minor changes were made with this update to reflect the latest
trends in observations and guidance. The forecast appears on
There is a chance for patchy dense fog over mainly the near shore
waters overnight. Will address with a marine weather statement if
A weak pressure gradient force will be across the waters through
Sunday morning, allowing for forecast winds and seas to stay
below SCA criteria.
Minimal SCA conditions mainly in the form of higher ocean seas
may be possible Sunday afternoon and night as easterly flow
increases following a back door cold frontal passage.
Mainly, if not entirely dry, through Thursday night.
Local minor flood impacts from heavier showers/tstms are possible
both late day Friday and Saturday, possibly still well inland well
N/W of NYC on Sunday.