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fxus61 kokx 261136 
afdokx

Area forecast discussion
National Weather Service New York New York
736 am EDT Wed Jul 26 2017

Synopsis...
high pressure will build in today, then move off the coast late
today through tonight. A weak cold front will slowly approach
on Thursday, and move through Thursday night. Low pressure will
then pass to the south on Friday. Another low will pass to the
south on Saturday while high pressure builds from the north. The
high will continue to build in through early next week.

&&

Near term /until 6 PM this evening/...
skies are mostly clear except across western Orange and parts of
NYC/NE NJ, but those areas should also clear out shortly. River
Valley fog has developed across CT, and should also do so across
the interior lower Hudson Valley before sunrise. After morning
lows in the 50s and lower 60s, today should be mostly sunny,
with some afternoon cu developing, more so from NYC Metro
north/west. As high pressure moves off the coast this afternoon,
NE winds should turn se, perhaps even S right at the immediate
coast with a superimposed sea breeze circulation. High temps
should reach at least the upper 70s and lower 80s per MOS blend
if not a little warmer.

&&

Short term /6 PM this evening through 6 PM Thursday/...
a frontal system will slowly approach from the northwest. Sided more
with the slower 00z GFS vs NAM, with precip holding off until
daytime Thu, first only slight chance pop inland in the morning
as low level ridging holds on closer to the coast, then chance
pop expanding southward with the front, and eastward from PA/New Jersey
with any convection developing via a Lee trough to the west.
Instability does not appear to be very great, with MLCAPE only
up to 500 j/kg and a cap persisting closer to the coast through
much of the day, but there may be enough deep layer shear to
help sustain a few strong storms. Think the overall severe risk
is marginal attm, and have played it down a little for the time
being.

After lows tonight from the mid/upper 50s east to 60s elsewhere,
highs on Thu should range from the upper 70s to mid 80s.

&&

Long term /Thursday night through Tuesday/...
a warm front will lift north Thursday night ushering warm humid
air across the area. Widespread showers/T-storms are expected
Thursday night. Both high and low temperatures will be closer to
normal.

Considerable model differences and low confidence in exact track
and timing of a low pressure system moving across the Ohio
Valley on Friday. At this time, looks like chance for showers
and thunderstorms will occur on Friday, but this system will
need to be monitored for the potential for heavy rainfall.
Highs on Friday will be in the mid/upper 70s with lows Friday
night in the mid/upper 60s.

For the weekend into early next week, any lingering chance of
precipitation Saturday morning will quickly diminish as high
pressure builds southward, bringing lower humidity and more
seasonable temperature values.

&&

Aviation /12z Wednesday through Sunday/...
high pressure builds over the area this morning before sliding
offshore this evening. A cold front will slowly approach during
the day on Thursday

VFR through the taf period. Fog this morning has resulted in LIFR
conditions at kswf, but any lingering low ceilings/visibilities
should rapidly improve to VFR this morning.

Light NE winds in the city and light and variable winds
elsewhere will begin to shift to the southeast-south-southeast by mid to late
morning.

New York Metro enhanced aviation weather support...

Detailed information, including hourly taf wind component forecasts,
can be found at: http:/www.Weather.Gov/zny/n90

Kjfk taf comments: no unscheduled amendments expected.

The afternoon kjfk haze potential forecast is green...which implies
slant range visibility 7sm or greater outside of cloud.

Klga taf comments: no unscheduled amendments expected.

The afternoon klga haze potential forecast is green...which implies
slant range visibility 7sm or greater outside of cloud.

Kewr taf comments: no unscheduled amendments expected.

The afternoon kewr haze potential forecast is green...which implies
slant range visibility 7sm or greater outside of cloud.

Kteb taf comments: no unscheduled amendments expected.

Khpn taf comments: no unscheduled amendments expected.

Kisp taf comments: no unscheduled amendments expected.

Outlook for 12z Thursday through Sunday...
Thursday-Thursday night...MVFR possible, with a chance of
showers and possibly a tstm. S-SW winds g15-20kt possible.
Friday-Saturday morning...MVFR or lower possible, with showers and
possibly a tstm. NE winds g15-25kt possible.
Saturday afternoon-Sunday...VFR.

&&

Marine...
quiet through Friday. Winds and seas should then gradually build
to advy levels Friday night and into Saturday night as a series
of low pressure centers pass to the south, with strengthening
north-NE flow. Seas should gradually subside Sunday and into next
week as high pressure builds in.

&&

Hydrology...
heavy rainfall is possible Thursday night into Friday, with a low
chance for urban and poor drainage flooding.

&&

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

&&

$$
Synopsis...fig/Goodman
near term...Goodman
short term...Goodman

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