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Area forecast discussion 
National Weather Service New York New York
629 PM EDT Thursday Jul 2 2015

Synopsis...
the first in a series of waves of low pressure will pass to the
south of the area tonight. High pressure then builds east across
the area on Friday. A second weak low will pass to the south on
Independence day. A broad area of high pressure will then build in
through the middle of next week.

&&

Near term /until 6 am Friday morning/...
forecast generally on track. The only changes wetr to remove
mention of thunder across the interior as there is little to no
instability. Also..have expaned the slight chance of showers to
include the western half of the area. Shortwave trough approaching
from the west has developed a few showers SW of the region...and
these could move in as the shortwave nears this evening.

Otherwise...the mean upper trough will remain across the east to
end the week with the first in a series of lows to pass south
tonight along a stationary front. Canopy of middle and high level
clouds will resides across the area for the first half of the
night with partly to mostly cloudy skies. The rain shield with the
low continues to stay south Li this evening...perhaps grazing the
South Fork of Li.

Lows tonight will range from the middle 50s in the interior...to the
lower 60s elsewhere. This is actually slightly below normal.

&&

Short term /6 am Friday morning through Friday night/...
short wave ridging on Friday will allow high pressure from the Great
Lakes to build east through Friday night ahead of the next piece of
short wave energy dropping into the Great Lakes. The latter of
which will send a second area of low pressure into the Middle
Atlantic States by daybreak Sat.

Friday into Friday night will be dry with highs once again in the upper
70s to lower 80s...and lows in the upper 50s to middle 60s. This is
at or slightly below normal. Clouds will be on the increase from
the SW Friday night.

There is moderate risk of rip currents on Friday.

&&

Long term /Saturday through Thursday/...
forecast for the 4th of July is tricky with models in disagreement
regarding our chances of rainfall. For the 12z suite...NAM is dry
during the day and night...with GFS/ECMWF/CMC showing some quantitative precipitation forecast
output. Most of the models would imply that the morning hours are
more likely to remain dry and any rainfall would be associated with
a wave of low pressure passing to the south. Still...will be keeping
at least a slight chance of showers for the southern zones for the
morning. For the afternoon and evening...an upper trough approaches
and could tap into enough instability to produce a shower or
thunderstorm for mainly the northwest zones. Will keep a slight chance of a
shower for the southern zones due to the proximity to the offshore
low. In any case...this does not look like a washout...but the
chances of a mostly sunny day doesn't look too high at this point.
Went slightly cooler than a mav/NAM MOS blend for high temperatures.

Sunday on the other hand looks like it will feature a good deal of
sunshine for much of the day with weak high pressure...but there
could be some cloud buildup in the afternoon over the eastern zones
as the flow aloft remains cyclonic. The atmospheric column at least
looks too dry for a mention of showers. Highs in the 80s.

Rest of the long term period probably remains dry for the most part
with high pressure in place. European model (ecmwf) remains a quick outlier with
bringing in rainfall associated with a weak wave of low pressure
along a stationary front to the south starting late in the day
Monday. Will go with dry weather for Monday through Tuesday
night...but leave in a slight chance of showers in the grids for
Wednesday and Thursday when the other guidance indicates that some
showers could occur. Highs in the 80s through Thursday...although
with the cloud cover...Thursday is forecast to be only around 80.

&&

Aviation /00z Friday through Tuesday/...
weak high pressure builds into the north...as waves of low pressure
pass to the south into Friday.

VFR through the taf period.

Seabreeze at all terminals by 21z...except at kswf where flow will
remain light and variable. Winds again become light and variable
throughout early this evening. North-northeast then NE winds under 10 knots develop
at kjfk/klga/kewr/kbdr/kisp/kgon early Friday morning. Seabreeze
should again develop at CT terminals/kjfk late Friday morning- early
Friday afternoon.

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: low chance of occasional gusts around 15 knots
with seabreeze this afternoon. Less than a 10 percent chance of
shower/thunderstorm through 00z.

Klga fcster comments: less than a 10 percent chance of
shower/thunderstorm through 00z.

Kewr fcster comments: 10 percent chance of shower/thunderstorm
through 00z.

Kteb fcster comments: timing of seabreeze may be +/- 1 hour. 10
percent chance of shower/thunderstorm through 00z.

Khpn fcster comments: timing of seabreeze may be +/- 1-2 hours. 10
percent chance of shower/thunderstorm through 00z.

Kisp fcster comments: less than a 10 percent or less chance of
shower/thunderstorm through 00z.

Outlook for 18z Friday through Tuesday...
Friday afternoon/night...VFR. Seabreeze likely in the afternoon.
Saturday...most likely VFR...with a low chance of rain with MVFR or
lower conditions.
Saturday night-Monday night...VFR.
Tuesday...most likely VFR...with very low chance MVFR or lower.

&&

Marine...
sub-Small Craft Advisory conditions through Friday night as weak low pressure passes
south of the waters tonight and high pressure builds to north on
Friday.

Winds and seas likely remain below Small Craft Advisory levels through the long
term period as a weak pressure gradient remains in place...resulting
in light winds. A swell could potentially bring ocean seas close
to 5 feet during Saturday...but confidence in this occurring is low.

&&

Hydrology...
widespread significant precipitation not expected.

&&

Tides/coastal flooding...
with a recent full moon...tidal departures of only 3/4 to 1 1/2
feet are needed for minor coastal flooding benchmarks to be reached
at the peak of the nighttime high tides the next few days. Minor
benchmarks could briefly be touched along the South Shore bays of
Nassau County through late this week.

&&

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

&&

$$
Synopsis...jc/dw
near term...ds/dw
short term...dw
long term...jc
aviation...maloit
marine...jc/dw
hydrology...jc/dw
tides/coastal flooding...

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