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Area forecast discussion 
National Weather Service New York New York
627 PM EDT Tuesday Jul 28 2015

Synopsis...
high pressure over the Ohio Valley builds east and into the area
through middle week. A cold front will approach Thursday...and pass
out to sea Friday morning. High pressure builds in through the
weekend...then a frontal system may impact the region during the
beginning of next week.

&&

Near term /until 6 am Wednesday morning/...
a weakening frontal boundary remains over the region this evening as
a weak shortwave passes northeast. A few isolated showers and
thunderstorms will be possible through 00z across southeastern
Connecticut. Otherwise...high pressure continues to build into
the region tonight. Skies will be mostly clear. It will be quite
muggy with lows falling into the 60s and 70s.

There is a moderate risk for rip currents at the ocean beaches
through Wednesday.

&&

Short term /6 am Wednesday morning through Wednesday night/...
another warm day is expected on Wednesday as ridging builds in at
the surface and aloft. A thermal trough will redevelop which will keep
the area in S/SW flow...with a continuation of high dew point air
across the region.

Highs on Wednesday look to climb into the upper 80s and lower to middle
90s...with the cooler temperatures near the coast. Expect dry
conditions on Wednesday with subsidence over the region.

Wednesday night will remain dry and muggy with lows only falling
into the upper 60s and 70s.

&&

Long term /Thursday through Tuesday/...
thermal ridge traverses the County Warning Area Thursday. However...south-southwesterly surface flow will
limit temperatures...especially Li and coastal CT. The high humidity however
will keep the hx in the 90s almost everywhere...and approach 100
across New Jersey zones and extreme southwestern New York. Locally higher values as well
into the interior CT River Valley. The advisory was extended for NYC
through 00z Friday. The NAM is developing thunderstorms during the day with the
prefrontal trough. This is a departure from the GFS and European model (ecmwf) previous
solution which delayed precipitation. Question is whether the forcing well ahead
of the front will be a sufficient trigger. Limited probability of precipitation to 30.
Heights fall Thursday night...so there will be better upper support for
thunderstorms. Coverage in question as sometimes it is difficult to initiate
after the passage of the prefrontal trough. Kept scattered coverage as a
result. Precipitation ends by early Friday morning...deep mixing on northwest flow keeps
temperatures a solid 5 degrees or more above climatology. Relative humidity significantly lower
however so hx close to the temperature. Hipres to the S with the storm
track mainly to the north through the weekend. The GFS does drop a stronger
shortwave through Sat night sparking some thunderstorms. Kept the forecast dry for now
with the general pattern favoring ares north of the County Warning Area. A blend of
guidance used for temperatures over the weekend. Humidity begins to creep
up Monday and Tuesday as southerly component flow strengthens ahead of an 500 mb
trough. Limited probability of precipitation to 20 with the bulk of the upper forcing still
close to the Great Lakes and Canadian/US border. Temperatures in the
pattern remain above normal.

&&

Aviation /00z Wednesday through Sunday/...
a weak low pressure trough will remain over the area...while high
pressure remains to the west.

VFR through this evening...though an isolated shower or thunderstorm may be
possible in vicinity of kgon toward evening. Kswf/khpn/kisp/kgon could see at
least MVFR conds late tonight...and kgon could go IFR or lower as
was the case last night. Expect any MVFR or lower conds to quickly
improve to VFR by 13z-14z.

Winds are coming around to the southeast-S at kewr and klga. Winds at other
terminals are S-SW...around 10 knots near the coast and less than 10 knots
inland. Winds tonight should veer SW and become light/variable
tonight...then pick up again to 5-10 knots by about 15z Wednesday.

New York metropolitan enhanced aviation weather support...

Detailed information...including hourly taf wind component forecasts
can be found at:
http:/www.Erh.NOAA.Gov/zny/n90 (lower case)

Kjfk fcster comments: no unscheduled amend expected.

Klga fcster comments: no unscheduled amend expected.

Kewr fcster comments: wind direction late this afternoon could vary from
140 to 180 true.

Kteb fcster comments: no unscheduled amend expected.

Khpn fcster comments: timing of arrival of southerly sea breeze
could vary up to an hour from forecast.

Kisp fcster comments: no unscheduled amend expected.

Outlook for 18z Wednesday through Sunday...
late Wednesday afternoon...VFR.
Wednesday night...MVFR visibility possible late.
Thursday...early morning haze with MVFR conds...then scattered
afternoon/evening thunderstorms with MVFR or lower conds.
Fri-Sunday...VFR.

&&

Marine...
a weak pressure gradient across the forecast waters will keep winds
and seas below small craft levels through Wednesday night. The
gradient wind from the south strengthens on Wednesday with the
possible development of a coastal jet. Still though...gusts should
remain below 25 knots...strongest west of Fire Island Inlet. Southerly
winds will then increase during the day on Thursday. The potential
exists for Small Craft Advisory conditions on the ocean by late afternoon...lasting through Thursday
night. Elsewhere winds blw Small Craft Advisory levels outside of thunderstorms. Winds and seas
then blw Small Craft Advisory levels until possibly Sat on the ocean where southerly flow
will increase again. Conditions likely improve to blw Small Craft Advisory levels on sun.

&&

Hydrology...
mainly dry conditions are forecast through Wednesday night. Around
3/4 inch of basin average precipitation is possible Thursday afternoon and Thursday night.
Locally higher amts possible in the strongest thunderstorms. Widespread
significant precipitation is not expected Fri-Tue.

&&

Climate...
record highs for Wednesday July 29 2015...

Location..........record high/year.........Forecast high
Newark....................100/1949.................95
Bridgeport.................96/2002.................91
Central Park...............99/1949.................94
LaGuardia..................97/1949.................94
Kennedy....................99/2002.................90
Islip......................96/2002.................89

&&

Okx watches/warnings/advisories...
CT...none.
New York...heat advisory until 8 PM EDT Thursday for nyz072>075-176-178.
New Jersey...none.
Marine...none.

&&

$$
Synopsis...BC/jmc
near term...British Columbia
short term...British Columbia
long term...jmc
aviation...je/Goodman
marine...BC/jmc
hydrology...BC/jmc
climate...

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