Scientific Forecaster Discussion
Area forecast discussion
National Weather Service New York New York
430 am EDT Monday Aug 31 2015
a back door cold front approaches later today and passes through
the region tonight. High pressure otherwise strengthens over the
middle-Atlantic through Thursday. A cold front will move through
Thursday night followed by high pressure through the weekend.
Near term /until 6 PM this evening/...
high pressure strengthens over the mid-Atlantic. Weak shortwave and
surface trough passes through the region this morning...but not
expecting any precipitation with its passage. Any showers that developed
during the overnight tapered off...and this system should pass
through the region dry. Any patchy fog across the interior will
dissipate shortly after sunrise.
Back door cold front approaches the region late in the day. As it
approaches...a southwest gradient tightens between that and high
pressure over the mid-Atlantic. This increased SW flow will result in
a warm and humid day as surface dewpoints rise into the middle and upper
Maximum temperatures today will top off in the upper 80s to around 90 for
most of the region...and the warmest temperatures will occur across NYC
and urbanized portions of NE New Jersey...where highs will top off in the
low to middle 90s. For NYC...the heat index should remain below 95
There is a moderate risk for rip currents at ocean beaches today.
Short term /6 PM this evening through Tuesday night/...
back door cold front passes through the region tonight. With
minimal upper level support...not expecting shra/tsra...so will
carry a dry forecast. Light northerly winds develop behind the
passage of the front...and surface dewpoints will drop a bit...
generally from the middle to upper 60s to the low to middle 60s. With
light winds and high relative humidity levels...some patchy fog
will develop across the interior and across eastern Long Island
late tonight and through daybreak Tuesday.
High pressure strengthens over the mid-Atlantic. Temperatures drop a bit on
Tuesday as compared to today...but will still top off in the upper
80s to around 90 with surface dewpoints in the low to middle 60s. Better
chance for sea breeze development at the coasts on Tuesday as surface
winds will be light during the day. The heat index should remain
below 95 on Tuesday in NYC.
Long term /Wednesday through Sunday/...
late Summer heat and humidity will be replaced by cooler temperatures
Friday through Sunday.
Wednesday through early Thursday...late Summer heat and humidity
will continue as air quality decreases under a stagnant dome of
high pressure. Temperatures will average at least 10 degrees
above normal. Although not in the latest forecast...can not rule out an
isolated thunderstorm Wednesday afternoon and evening with the development of a day time
Day time highs will be in the lower 90s both Wednesday and Thursday with heat
index values approaching 95 degrees across NYC and urban NE New Jersey.
Late Thursday-early Friday...a stronger back door cold front is forecast
to provide some relief initially in the form of widely scattered thunderstorms
mainly Thursday afternoon - evening. Forecast a pop of 20 percent...which may need to be
increased in later forecasts.
Late Friday through Sunday...maritime polar air on east winds replaces
the maritime tropical air mass with cooler temperatures.
Drought will continue to develop region wide...but especially
across Long Island and southern CT through the period with no
significant widespread rainfall in the forecast.
Aviation /08z Monday through Friday/...
a weak trough of low pressure remains near the terminals today. A
cold front will pass through the terminals from the north and east
VFR through the taf period.
Generally light SW or variable winds through sunrise. West-west-southwest winds
around 10 knots develop by middle to late morning and into the early
afternoon. Wind speeds should increase during the afternoon...10
to 15 knots. Gusts to around 20 knots for city terminals. Gusts end
after sunset with speeds around 10 knots.
... 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: moderate confidence in wind forecast. Sea
breeze likely stays south and east of terminal...with low chance
for it to move through after 19z.
Klga fcster comments: moderate confidence in wind forecast.
Kewr fcster comments: moderate confidence in wind forecast.
The afternoon kewr haze potential forecast is green...which implies
slant range visibility 7sm or greater outside of cloud.
Kteb fcster comments: moderate confidence in wind forecast.
Khpn fcster comments: moderate confidence in wind forecast.
Kisp fcster comments: moderate confidence in wind forecast.
Occasional wind gust to 20 knots possible in the afternoon.
Outlook for 06z Tuesday through Friday...
Monday night-Wednesday night...VFR. Afternoon sea breezes
probable each afternoon.
Thursday-Thursday night...VFR. Isolated showers/thunderstorms
possible. Afternoon sea breezes probable.
Friday...VFR. East-northeast winds g15-20kt.
SW pressure gradient tightens today between an approaching back door
cold front and surface high pressure off the mid-Atlantic. Winds and seas
should remain below Small Craft Advisory/Small Craft Advisory levels on all
waters... but seas may briefly build to 5 feet on the central and
eastern ocean waters this afternoon.
Otherwise...conds will remain below Small Craft Advisory conds through Thursday.
Late Thursday-Thursday night...widely scattered thunderstorms possible ahead of an
approaching cold front.
Friday...the next chance for Small Craft Advisory level winds and
seas will occur as winds shift from the east at 15-20 knots following
the passage of a cold front as high pressure moves east across New
Thursday afternoon-early Friday...widely scattered thunderstorms possible ahead of
approaching cold front with less than 1/4 inch rain.
No widespread significant rainfall is forecast through next
with a recent full moon...brief minor inundation is possible
during the times of high tide across the typically vulnerable
coastal locales for the start of the work week.