Area Forecast Discussion
Issued by NWS Upton, NY-- Highlight Changed Discussion --
-- Discussion containing changed information from previous version are highlighted. --
FXUS61 KOKX 270239
Area Forecast Discussion
National Weather Service New York NY
1039 PM EDT SUN JUN 26 2016
High pressure remains across the region into Monday and drifts
east late Monday into Monday night as a slow moving cold front
approaches. The cold front approaches Tuesday and moves across
early Wednesday. Afterwards, it will linger south of Long Island
during the day Wednesday before moving farther offshore Wednesday
night. Weak high pressure returns Thursday through Friday. Another
cold front approaches late Friday moving across Saturday and
moving southeast of the region by next Sunday.
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
Surface high pressure remain centered east of Long Island
tonight. Aloft a longwave trough moving through south central
Canada reaches southeastern Canada by 12z Monday. The upper ridge
over the area weakens late tonight as a closed low over the
western Atlantic drifts westward and gets picked up by the
The airmass in place the last couple of days remains tonight with
a slight increase in low level moisture on a southerly flow. As
such...will have patchy fog/stratus potential across the far
eastern coastal zones.
.SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/...
-- Changed Discussion --The longwave upper trough continues to move slowly into eastern
Canada with a shortwave rotating into the trough, extending into
the Great Lakes region by late Monday night. The upper low over
the western Atlantic get fully integrated into the upper trough
during Monday. Meanwhile, a weak cold front will be approaching.
The warm and humid airmass remains in place ahead of the cold
front. There will be weak lift and instability by Monday afternoon
with better instability by Monday evening inland. Will have slight
chance pops by Monday afternoon across the western zones with only
showers. This may still be too quick. Pops increase Monday night,
still at chance, and progress slowly east through Monday night.
Will have isolated thunder during the evening with the best
There is a borderline low to moderate risk for the development of
rip currents at Atlantic ocean beaches Monday. If incoming swell
energy falls to around 1 ft as depicted by guidance...rip
development risk would be low...but some uncertainty on how
quickly that will occur. With that said...15-20 kt afternoon
coastal jet development should have rip risk increasing to
moderate across NYC and Western LI beaches in the late
afternoon/eve with increased wind waves.
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.LONG TERM /TUESDAY THROUGH SUNDAY/...
The shortwave currently in the vicinity of Montana will be
approaching the Northeast by early Tuesday. This will be associated
with a deepening trough and this gradually moves in through Tuesday
evening. Then the trough axis will be moving across on Wednesday.
After that, there will still be a lingering upper level trough in
the Northeast but less amplified. The associated jet max will be
moving east of the region by Wednesday night with the next jet
streak not moving in until Friday night into next weekend.
At the surface, there will be an approaching cold front Tuesday and
this front will move across early Wednesday. With low pressure
developing along it, it may linger nearby just south of Long Island
during the day Wednesday. The front will then move farther offshore
Wednesday night with weak high pressure returning for Thursday
through Friday. Another cold front approaches late Friday into
Saturday and will eventually move offshore for next Sunday.
In terms of weather, there will be two periods where rainfall will
become more probable, Tuesday through Wednesday and Friday afternoon
through Saturday night. Each of these periods will have chances of
showers and thunderstorms as there will be low level instability and
an upper level jet streak moving across. The relatively higher
chances are with the Tuesday and Tuesday Night timeframe.
In terms of temperatures, most daytime highs Tuesday and Wednesday
will be in the upper 70s to lower 80s and then Thursday through next
weekend will be mainly in the low to mid 80s. Lows forecast are
pretty consistent during the long term period with values mainly
ranging from the upper 50s to upper 60s.
.AVIATION /03Z MONDAY THROUGH FRIDAY/...
High pressure remains just to the east of the region...with a
frontal system approaching Mon Night.
VFR...except for potential radiation/advection fog/stratus late
tonight at KGON with light onshore flow under mostly clear skies.
A few mvfr/ifr cigs possible at coastal terminals late
tonight...gradually lifting above 3 kft through Mon morning. Low
prob of a shower at KSWF late Mon.
Light s/ssw tonight...increasing Mon Morning. S/SE seabreeze
development expected at all but KSWF Mon afternoon. At KJFK/KLGA
moderate potential for S winds 15-20 with gusts to 25 kt in late
afternoon/early eve with coastal jet development...elsewhere
generally 10 to 15 kt with gusts to 20 kt.
.OUTLOOK FOR 00Z TUESDAY THROUGH FRIDAY...
.Monday Night into Tuesday morning...S winds G20KT along the coast
in the early evening. MVFR or lower conditions possible, with
showers mainly from NYC metro north/west, and low clouds/patchy
fog along the coast especially KGON/KISP.
.Tuesday afternoon and night...MVFR or IFR conditions likely in
showers and tstms. Stratus and fog possible at night, with IFR or
lower conditions likely at coastal terminals.
.Wednesday morning...IFR or lower conditions still possible via
morning fog/low clouds and any stray showers.
.Wednesday afternoon through Thursday...VFR.
.Friday...MVFR or lower conditions with showers/tstms possible in the
late afternoon from NYC metro north/west, and throughout at night.
High pressure remains over the waters tonight into Monday and
drifts east late in the day into Monday night. As the high drifts
east winds will increase Monday afternoon. Low level winds
increase and occasional gusts to near small craft levels will be
possible, mainly west of Fire Island Inlet and New York Harbor
Monday afternoon into the early evening. Otherwise, winds and seas
will remain below small craft levels on all the waters tonight
through Monday night.
Overall the pressure gradient remains weak during the long term
period Tuesday through next weekend. Seas and winds are forecast to
remain small craft advisory thresholds.
From late Monday afternoon into Monday night a few hundredths of
an inch up to 2 tenths of an inch of rainfall will be possible,
mainly from southwestern Connecticut into northeastern New Jersey
with the highest amounts across Orange county into western
Overall, no significant widespread rainfall expected Tuesday and
through the upcoming week. The showers and thunderstorms Tuesday
and Tuesday Night are forecast to produce an additional 0.15 to
0.3 inch of rain basin averaged.