Area Forecast Discussion
Issued by NWS Upton, NY-- Highlight Changed Discussion --
-- Discussion containing changed information from previous version are highlighted. --
FXUS61 KOKX 290802
Area Forecast Discussion
National Weather Service New York NY
402 AM EDT WED JUN 29 2016
A cold front will move slowly east across the Tri-State region
early today. Weak high pressure builds in tonight through
Thursday. High pressure weakens across the region Thursday night
into Friday with a cold frontal passage late Friday night into
Saturday morning. High pressure then returns behind the front and
prevails through early next week.
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Showers continue to decrease across the region, with only a slight
chance for showers possible through daybreak as a cold front
slowly moves east. Visibilities have improved in many areas as
well, though there are some observations reporting anywhere from
2 to 5 miles surface visibilities, so kept the mention of patchy
fog through daybreak as well.
Weak high pressure will build in as the cold front pushes off the
east coast. It will be dry for the most part today. However, there
is the potential for isolated showers and a passing thunderstorm,
mainly across Connecticut as a vorticity max moves through. With
sea breezes developing, this could provide additional lift for
precipitation to occur. Long Island could also see a shower
develop along the sea breeze, however, given that it will be
situated farther from the approaching vorticity maximum, chances
will be less likely here. Therefore, did not mention any showers.
Highs today will be seasonable. Humidity levels will drop somewhat
across the entire areas, but more so for western areas as drier
air move in. A rather humid air mass will still be in place for
eastern sections, and this would also help to produce showers and
thunderstorms for Connecticut.
.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
Dry conditions should persist through Thursday with high pressure
continuing to build in. Temperatures will continue to be
seasonable, with humidity levels continuing to drop into Thursday.
.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
Upper low south of Hudson Bay will rotate through the mean trough
and pass through eastern Canada and the Northeast by the close of
the weekend. The latter of which will send a cold front across
the area late Friday night into Saturday morning, preceded by a
round of showers and thunderstorms Friday afternoon and evening
along and ahead of a pre-frontal trough. There is the potential
for some organization with moderate deep-layer shear and CAPES
over 1000 J/KG across much of the area. In addition, models are
pointing toward showers developing overnight Thursday as moisture
returns around the western periphery of offshore high pressure,
interacting with mid level short wave energy. The forecast is
slowly trending in this direction. High pressure follows for the
weekend into early next week. The 00Z GFS bring a southern branch
system close enough to the area Tuesday for showers, however, the
ECMWF is suppressed to the south. Subsequent model trends will
need to be watched, but for the time will keep the forecast dry.
Temperatures continue to remain near seasonable levels throughout
.AVIATION /07Z WEDNESDAY THROUGH SUNDAY/...
A cold front will move slowly east across the local area today
followed by high pressure tonight.
SCT SHWRS will end from W to E by 12z.
Because winds will remain light overnight, areas of IFR/LIFR fog,
locally dense will form in a humid air mass.
CIGS from the NYC Metro area East will range from LIFR to MVFR
until 12z, with gradual improvement N and W of NYC.
For tonight...forecast uncertainties remain with the locations and
timing for fog development.
For Wednesday...forecast uncertainties remain with timing the
development of sea breezes around 10 kt following NW winds of
10-15 kt between 12z and 17z.
Can not rule out an isolated or even widely SCT TSTMs aft 18z area
.OUTLOOK FOR 06Z THURSDAY THROUGH SUNDAY...
.Wednesday night through Friday morning...VFR.
.Friday afternoon and night...MVFR or IFR conditions possible in
.Saturday and Sunday...VFR.
Patchy fog is possible over all waters through daybreak.
Thereafter, visibilities should improve. Conditions should remain
below Small Craft Advisory levels in the short term.
Winds and seas are forecast to remain below small craft advisory
levels from Friday through the holiday weekend.
No significant rainfall is expected from Wednesday through
Scattered showers and thunderstorms are possible Friday afternoon
into early Saturday. Antecedent conditions are very dry, so
widespread hydrology issues are not expected.