Scientific Forecaster Discussion
Area forecast discussion
National Weather Service New York New York
123 am EDT Tuesday Sep 1 2015
high pressure builds into the region behind a weak boundary
tonight through Wednesday. A weak front moves through the region
Wednesday night...with a stronger cold front moving through
Thursday night. High pressure will then build in from the north
for the weekend into early next week.
Near term /until 6 am this morning/...
forecast is on track. Only minor adjustments needed to hourly
T/TD/sky and winds.
Surface trough/weak cold front should push S of Long Island by
midnight. Light northerly winds develop behind its passage...and
surface dewpoints will a few degrees. With light winds and high
relative humidity levels...some patchy fog may develop across the
interior and across eastern Long Island late tonight and through
Followed a mav/met blend for temperatures tonight. Expect lows to
drop into the 60s and lower 70s. Middle 70s are expected in and around
Short term /6 am this morning through 6 PM Wednesday/...
high pressure builds over the middle-Atlantic through the short term
period. Expect a better chance afternoon seabreezes on Tuesday as
surface winds will be light during the day. Temperatures will once
again top off in the upper 80s to around 90 with surface dewpoints in
the low to middle 60s. The heat index should remain around 90 on
Tuesday in NYC.
Tuesday night will remain clear with temperatures falling into the
60s and lower 70s. Middle 70s are expected in the NYC metropolitan.
Long term /Wednesday night through Monday/...
a weak southern stream shortwave will move south of the region late
Wednesday...followed by glancing shortwave energy from a strong northern
stream upper low Thursday. Models are in decent agreement with
phasing these energies well east of the NE US...with upper ridging
building into the region for the weekend through early next week.
Late Summer heat and humidity will continue Wednesday and Thursday. A weak
trough and shortwave energy moving into the region late in the day
Wednesday...may be enough to set off an isolated shower/thunderstorm
off the higher terrain of the interior. Stronger Canadian cold
front approaches from the north late Thursday in the wake of
shortwave energy digging southeast through the Canadian Maritimes. This
will bring potential of isolated/scattered showers/thunderstorms late
Thursday into Thursday night as the front sag south. 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.
Canadian high pressure builds south-southwest across the region Friday into
Saturday. This will advect a cooler and drier Canadian maritime
airmass into the region for Friday and Sat. Although humidity levels
should be in the 50s...gusty east winds on Friday may pose a
enhanced concern for spread of brush fires due to high kbdi values
and available fine fuels. Highs are still expected to run near to
slightly above seasonable...lower 80s to around 85.
Dry conditions are expected through early next week as high pressure
sinks southeast of the region. This will also spell a steady moderation in
humidity and unseasonable warmth through early next week.
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 /06z Tuesday through Saturday/...
a weak cold front moves across the terminals during the early
morning hours. Winds shift from west to N/NW...but remain less than
10 knots. Afternoon sea breezes will develop at coastal terminals.
VFR...except a brief period of MVFR fog at kswf towards daybreak.
Outlook for 06z Wednesday through Saturday...
tonight...VFR. Light winds.
Thursday-Thursday night...VFR. Isolated showers/thunderstorms
possible. Afternoon sea breezes probable.
Friday...VFR. East-northeast winds g15-20kt.
a weak cold front will move across the area waters
tonight...followed by high pressure. Conditions will remain below
small craft levels through Tuesday night.
Sub Small Craft Advisory conditions expected Wednesday with a weak trough in the region and
Thursday ahead of an approaching cold front.
The next chance for Small Craft Advisory level winds and seas is
Friday following the passage of a cold front. Potential exists for
easterly winds of 15 to 20 knots and ocean seas building to 5 to 6 feet
on the ocean...with Small Craft Advisory gusts possible on Li sound and nearshore
no widespread significant rainfall is forecast through next weekend.
near term...British Columbia
short term...British Columbia