Scientific Forecaster Discussion
Area forecast discussion
National Weather Service New York New York
437 am EDT Friday Jul 3 2015
high pressure builds today...then gives way to low pressure that is
expected to track to the south Saturday. High pressure will build
across from Sunday into Monday. A weak low and associated warm
front will then lift slowly up the coast Monday night into Tuesday
night. A slow moving cold front will then approach on Wednesday
and possibly linger into Thursday.
Near term /until 6 PM this evening/...
initial shortwave departs to the northeast this morning...with
weak ridge aloft building in behind.
Surface high pressure builds toward the area today. Satellite indicates
clearing across the area...and models forecast plenty of dry air and
MOS temperatures are in good agreement...and expect highs to rise to
There is moderate risk of rip currents today.
Short term /6 PM this evening through Saturday night/...
upstream trough is expected to track toward the area this time
frame...with surface low pressure moving east and passing just south
of Long Island late Saturday and Saturday night. Models close with
regard to surface low track...with CMC slower.
The forecast trend is wetter as analysis of 00z model suite
indicates plenty of lift out ahead of this trough...and to the
north of the surface low.
Clouds will be on the increase tonight...with mainly cloudy skies
Saturday. After collab with surrounding offices...will make The Jump
to likely probability of precipitation Saturday due to this wetter consensus.
Temperatures tonight will settle in the upper 50s to the middle 60s as
Then...cooler readings seem likely Saturday due to clouds...rain and
northeasterly wind flow. Expect temperatures to rise only to the upper
60s to lower to middle 70s...well below normal. The area is obviously
on the cool side of this system and not much in the way of
instability is noted. Stratiform rain.
The low and upper trough pass east Saturday night. Would anticipate
improving conditions during the evening and overnight as rain ends
and skies gradually clear.
Long term /Sunday through Thursday/...
Sunday should feature a good deal of sunshine as weak high
pressure builds across. Could see some afternoon cumulus especially
across the interior as cyclonic flow persists aloft and as a weak
thermal trough develops.
Some changes are now in the offing for what was previously a dry middle
week forecast. First...upper ridging will pass across Sunday night
and pass to the northeast on Monday...allowing high clouds from a weak
disturbance lifting north into the middle Atlantic region to spread in
Monday into Monday evening. This disturbance should eventually arrive late
Monday night into Tuesday with the next chance of precipitation.
Then an upper trough traversing southern Canada will drive a cold
front toward the area on Wednesday. With global models indicating quasi-
zonal west-southwest flow aloft across much of the eastern and central
states...the tail end of this front should become quasi-stationary
as well...with a series of convectively generated middle-level
disturbances riding along it. This will mean continued chances for
convection both diurnal and non-diurnal from Wednesday into
Thursday...depending on the timing of these disturbances.
Aviation /09z Friday through Tuesday/...
high pressure builds from the Great Lakes region this
morning...sliding offshore during the afternoon. A wave of low
pressure approaches from the Middle Atlantic States tonight.
VFR through 06z Sat.
Moderate to high confidence in wind forecasts. Seabreezes develop
at coastal terminals late this morning and afternoon. Direction at
kbdr/kgon may be 20-30 degrees on either side of forecast due to
hybrid synoptic/seabreeze flow.
..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: timing of the seabreeze could be +/- 1-2
Klga fcster comments: timing of the seabreeze could be +/- 1-2
Kewr fcster comments: timing of the seabreeze could be +/- 1-2
The afternoon kewr haze potential forecast is green...which
slant range visibility 7sm or greater outside of cloud.
Kteb fcster comments: timing of the seabreeze could be +/- 1-2
Khpn fcster comments: timing of the seabreeze could be +/- 1-2
Kisp fcster comments: timing of the seabreeze could be +/- 1-2
hours. Direction may be 20-30 degrees on either side of forecast
due to hybrid synoptic/seabreeze flow.
Outlook for 06z Saturday through Tuesday...
Friday night...VFR. Light southeast flow...becoming east-NE late.
Saturday...MVFR likely with rain developing. Low chance of IFR.
East/NE winds 10-15g20kt...becoming north late.
Saturday night-Tuesday...VFR. Northerly winds diminishing Sat evening.
with high pressure building today...winds will remain
rather light across the area waters. Fairly tranquil seas can be
expected as well...mainly 2 to 3 feet in swell today over the ocean
By tonight...winds will turn toward the east ahead of low pressure
that will approach the waters from the west. This low passes nearby
Saturday. As such...winds increase as they back to the
north/northeast. Over the ocean...winds may approach Small Craft Advisory thresholds.
Not enough confidence though in this occurring...so will hold off on
Seas build late tonight and through the day Saturday. However...not
too confident in reaching 5 feet until possibly Sat evening.
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.
basin average rainfall should remain below a 1/2 inch Saturday.
No hydrologic issues are anticipated.
Significant precipitation could occur at some point during the
middle of next week as a weak low and warm front move up the coast
on Tuesday...then as a cold front approaches and stalls nearby Wednesday
into Thursday. Predictability is too low to offer any specifics at this time.
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 couple of days. Minor
benchmarks could briefly be touched along the South Shore bays of
Nassau County tonight and possibly Saturday night. In
addition...winds increase during the day Saturday from the
northeast...so the daytime high tides may need to be monitored as
near term...precipitable water
short term...precipitable water