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Area forecast discussion 
National Weather Service New York New York
410 PM EDT Monday Jul 28 2014

Synopsis...
Canadian high pressure builds over the region tonight and remains
entrenched through the week. Weak low pressure may develop late
this weekend along the coast into early next week.

&&

Near term /until 6 am Tuesday morning/...
the bulk of the precipitation associated with instability from
the upper low remains north of New York City/Long Island the rest
of the afternoon. The line of mainly showers from Albany New York
southwest to near State College PA as of 3 PM will need
watching...but due to limited cape, is expected to remain steady
state as it approaches northern New Jersey towards 6 PM. Ahead of this
line...isolated showers are expected. Severe threat is limited.

After 6 PM the line should begin to quickly diminish as it
approaches NYC and Long Island towards 7-8 PM.

There remains is a moderate risk for the development of rip
currents along the Atlantic Ocean facing beaches through this
evening.

Slow clearing overnight with lows in the middle 50s to middle 60s in NYC.
Winds gradually subside after midnight.

&&

Short term /6 am Tuesday morning through Tuesday night/...
sun gives way to afternoon cumulus that "pancake" under the
subsidence to broken at times.

Clear Tuesday night.

Maximum/mins are a blend of MOS which had little spread.

There is a moderate risk for the development of rip currents
along the Atlantic Ocean facing beaches the afternoon and evening
on Tuesday.

&&

Long term /Wednesday through Monday/...
upper level trough over the eastern half of the US will be the
dominating feature for the second half of the week before weakening
this coming weekend. At the surface...high pressure will build in
Wednesday-Friday with a surface low along the stalled front well shore backs
towards the northeast.

Generally expecting dry and quiet Wednesday through Wednesday night. 12z NAM and
GFS both hinting at isolated shower/thunderstorm development well north/west of
NYC metropolitan...corresponding with the region under a passing shortwave.
Have been going back and forth the past couple of days on whether
anything will form so went ahead and included a low end slight chance
for precipitation for the afternoon with just enough moisture in the lower atmo
being injected in with the southwesterly flow. Overall though...majority of
the area will enjoy dry weather. Similar story on Thursday with another
passing shortwave and a bit more moisture in the atmo...closer to
normal values for this time of year. Again just have mention for
slight chance thunderstorm well north/west of NYC metropolitan.

Potential for a bit more active period Friday heading into the
weekend. At the surface...the lingering stalled frontal system well
offshore begins to back as a warm front...with an area of low
pressure forming along the middle Atlantic coast line. Aloft...the
dominating closed low/associated deep trough begins to edge off to
the north and east. The region will remain positioned though under a
broad trough...with multiple decent shortwaves riding the
flow...each bringing enough forcing to trigger showers and/or thunderstorms.
Have attempted to time out the passing and included probability of precipitation to
correspond where there is better model agreement on the
timing...Friday night and then again Sat aftn/evening. Models diverge
however on the solution sun-Monday with the 12z GFS being the more
progression in weakening the trough into almost a zonal flow while
the European model (ecmwf) lingers the trough into the work week. Taking a blend of
the solutions for now with the high uncertainty...have mention of
slight chance probability of precipitation Sun afternoon-Monday evening. The trend suggests any precipitation
sun might be isolated in nature...with more scattered showers and thunderstorms
Monday with both a passing shortwave and the front stalling just
east of the area. As of now...the threat of any strong to severe
storms looks to be very minimal.

Under the persisting trough...temperatures will hover a few degrees below
normal through the end of the week. Rising heights by the end of the
weekend will aid in pushing temperatures to right around normal values.

&&

Aviation /20z Monday through Saturday/...
surface cold front and deep upper trough move across the region this
evening. Some scattered showers...possibly a thunderstorm...will develop
late this afternoon. Not confident enough in any of the showers
impacting any given terminal...so will leave out of the latest
tafs. Will include a tempo group for some showers at kswf...as the
bulk of the activity will stay north of the region. VFR conds
otherwise.

SW winds will increase to 15-20 knots with gusts as high as 30 knots.
Winds diminish to 10-15 knots with 15-23 knots gusts this evening before
turning west-northwest and diminishing further to 8-12 knots.

General west flow at 10 knots or less on tap for Tuesday.

... 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: winds through this evening may not be as
strong as forecast.

Klga fcster comments: winds through this evening may not be as
strong as forecast.

Kewr fcster comments: winds through this evening may not be as
strong as forecast.

Kteb fcster comments: winds through this evening may not be as
strong as forecast.

Khpn fcster comments: winds through this evening may not be as
strong as forecast.

Kisp fcster comments: no unscheduled amendments expected.

Outlook for 18z Tuesday through Saturday...
Tuesday afternoon-Wednesday...VFR.
Thursday-Friday...isolated showers/thunderstorms possible in the
afternoon/early evening...mainly west of a line from kbdr to kfrg.
Otherwise...VFR.
Saturday...VFR.

&&

Marine...
Small Craft Advisory. Southwest winds will continue to increase
the rest of the afternoon in the wake of a cold front. Gusts, quite
strong for this time of year, to near 30 kts though the evening.

Wind diminish late overnight with sub-Small Craft Advisory conditions expected Tuesday.
Note that wave-watch guidance appears too high based on initial
conditions.

Sub-Small Craft Advisory conditions on all waters then through the remainder of the
week...with a possible return to 25 knots gusts and 5 feet seas over the
weekend depending on the track of the surface low.

&&

Hydrology...
scattered convection is expected this afternoon with no
significant hydrologic issues are expected through the end of the
week.

&&

Okx watches/warnings/advisories...
CT...none.
New York...none.
New Jersey...none.
Marine...Small Craft Advisory until midnight EDT tonight for anz330-335-
338-340-345.
Small Craft Advisory until 6 am EDT Tuesday for anz350-353-355.

&&

$$
Synopsis...Sears/tongue
near term...tongue
short term...tongue
long term...Sears
aviation...mps
marine...Sears/tongue
hydrology...

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