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Area forecast discussion 
National Weather Service New York New York
431 PM EDT Wednesday Jul 30 2014

Synopsis...
weak high pressure over the middle-Atlantic region moves offshore
tonight. Upper level disturbance passes north and west of the
region on Friday. A frontal boundary will develop along the coast
through the weekend. A cold frontal passage is likely for the
beginning of next week.

&&

Near term /until 6 am Thursday morning/...
weak shortwave passes through the region this evening. Any clouds
associated with it will dissipate this evening with the loss of
diurnal heating. High pressure over the middle-Atlantic moves offshore as
well...and resulting return flow will allow for an increase in
moisture over the region.

Middle-level clouds will spread into areas west of the Hudson River
towards daybreak Thursday. With the increase in low-level
moisture...some patchy fog is possible...mainly in the outlying
areas.

Lows tonight will drop into the middle and upper 60s in/around
NYC...while most other areas will drop into the upper 50s to low
60s. Lows in outlying portions of the lower Hudson Valley...
interior portions of southern CT...and The Pine Barrens of Long
Island will drop into the middle 50s.

&&

Short term /6 am Thursday morning through Thursday night/...
fairly strong 500 mb shortwave pivots around closed low near the
Hudson Bay in Canada and passes just north and west of the local
County Warning Area. Cape values will rise close to 1000 j/kg and 0-6 km bulk
shear will increase to 40-50 knots. The lifted index will be fairly
weak... generally ranging from -1 to -2c. With the bulk of the
energy staying north of the region...will keep probability of precipitation capped at
chance...and will expect scattered showers/thunderstorms starting in the
late morning...tapering off by Thursday evening. Do think storms
will be hard to make it to far southeast CT and eastern Suffolk
County...and will keep probability of precipitation capped at slight chance for those
areas.

Maximum temperatures generally running near or a couple of degrees below
normal on Thursday with highs in the low 80s for NYC...Long
Island...NE New Jersey...and in the upper 70s to around 80 elsewhere.

Any showers/thunderstorms will taper off in the evening. Light...onshore
flow remains over the region with surface dew points rising into the
low-middle 60s. Patchy fog possible after midnight Thursday night
away from NYC.

&&

Long term /Friday through Wednesday/...
Friday...instability across mainly the interior areas will set the
stage for scattered convection during the afternoon hours.

Saturday and Sunday...a surface low pressure along the Atlantic
coast...and subtropical moisture associated with a Bermuda ridge
will aid in the development of showers/thunderstorms Saturday and
Sunday. The 12z/GFS continues to have the best forcing for chance of
showers to be on Sunday...while 12z/European model (ecmwf) shows the best forcing to
be on Saturday. Will continue with previous thinking and maintain
40/50 pop for the weekend.

Monday and Tuesday...a low pressure moving through the Great Lakes
region will bring a cold front towards the area. This will keep schc
probability of precipitation on Monday...with drier air moving in on Tuesday.

Temperatures through the extended period will be close to seasonable
levels.

&&

Aviation /21z Wednesday through Monday/...
weak high pressure builds offshore through tonight.

VFR through the taf period. Could see ceilings around 5000 feet
develop by middle-late Thursday morning. There is a slight chance areas
north/west of NYC could see an isolated rain showers Thursday prior to 18z...but
probability of this is too low to reflect in the tafs at this
time.

Seabreeze already through kjfk/kbdr/kgon/kisp. Should push through
klga/khpn later this afternoon. For now expect to approach but
not move through kteb and kewr...so only back winds to SW at those
locations. Winds become light and variable/light SW again tonight.
Seabreeze should develop a tad early Thursday than it did today.

..NY 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: changes in wind direction/speed could be off
+/- 1-2 hours.

Klga fcster comments: seabreeze timing could be off +/- 1-2 hours.

Kewr fcster comments: no seabreeze forecast...but changes in wind
direction/speed could be off +/- 1-2 hours.

Kteb fcster comments: no seabreeze forecast...but changes in wind
direction/speed could be off +/- 1-2 hours.

Khpn fcster comments: seabreeze timing could be off +/- 1-2 hours.

Kisp fcster comments: changes in wind direction/speed could be off
+/- 1-2 hours.



Outlook for 18z Thursday through Monday...
Thursday afternoon-Monday...VFR...except MVFR or lower possible
in any isolated-scattered rain showers/thunderstorms that are possible mainly in the
afternoon/evening each day.




&&

Marine...
with high pressure over the waters...can expect sub-Small Craft
Advisory conds through Friday. Winds and seas will remain below
Small Craft Advisory levels through the extended period.

&&

Hydrology...
brief...locally heavy downpours possible in scattered thunderstorms on
Thursday...but not expecting more than localized nuisance
flooding. A humid air mass will be conducive to the development of heavy
showers this weekend.

&&

Okx watches/warnings/advisories...
CT...none.
New York...none.
New Jersey...none.
Marine...none.

&&

$$
Synopsis...fig/mps
near term...mps
short term...mps
long term...figure
aviation...maloit/met
marine...fig/mps
hydrology...fig/mps

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