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Area forecast discussion 
National Weather Service New York New York
812 PM EDT Monday may 25 2015

Synopsis...
a Bermuda high remains in place through the end of the week with
a weakening frontal boundary dissipating across the area on
Thursday. A stronger cold front may impact area late next weekend.

&&

Near term /until 6 am Tuesday morning/...
forecast is on track. Temperatures aren't dropping quite as fast as
forecast this evening...so minor adjustments here. Also adjusted sky
forecast in the database to reflect more of a partly cloudy to
mostly clear condition overnight. With the ridge over the NE...most
of the cloud cover should remain north of the forecast area.

Otherwise...dry conditions with southerly flow decreasing
tonight. Not anticipating any fog/stratus tonight...although
wouldn't be surprised if a few low clouds are floating around
towards morning.

Used a blend of mav/met/ecs MOS for lows tonight in the middle 60s
in/around NYC and in the upper 50s to low 60s elsewhere.

&&

Short term /6 am Tuesday morning through Tuesday night/...
Bermuda high continues to impact the region on Tuesday with
increasing S-SW winds through the afternoon. This will continue to
usher a warm and increasingly humid airmass into the region with
highs generally in the low to middle 80s in/around NYC...areas mainly
west of the Hudson River...and across interior portions of
southern CT. Most other areas will top off in the low 80s...while
Long Island and coastal CT will top off in the middle to upper 70s.
Immediate coastal areas right along the shore will struggle to
warm above the lower 70s due to the onshore flow and water temperatures
still in the 50s.

Weak middle-level shortwave will pass to the north of the region
Tuesday afternoon/evening. With forecasted cape values over 1500
j/kg across the interior...and a steepening lapse rate...can
expect at least some scattered showers/thunderstorms in afternoon/evening.
Models also indicating some precipitation in the afternoon/evening for
the lower Hudson Valley. Will cap probability of precipitation at chance...as activity
should not be widespread. Will not mention showers/thunderstorms for
coastal areas as sea breezes should have a stabilizing effect on
the area...and any storms that pop up will not be able to last in
that environment.

Some fog/stratus possible starting Tuesday night due to the
persistent increase in low-level moisture...especially for coastal
areas. Will introduce patchy fog in the forecast.

NAM/GFS/ECMWF also showing another shortwave passing through the
area sometime after midnight Tuesday night and through Wednesday
morning. Hard to tell exactly where the convection would set
up...but will go ahead and introduce chance probability of precipitation for showers/thunderstorms
late Tuesday night.

There is a moderate risk for rip current development at Atlantic
Ocean beaches on Tuesday.

&&

Long term /Wednesday through Monday/...
a high amplitude ridge along the eastern Seaboard will expand
westward back to the MS River Valley as short wave energy over the
Great Lakes dampens and lifts to the NE Wednesday into Thursday. This will
allow the subtrop ridge...Bermuda high...to remain in place
through next weekend...pumping in warm...humid air across the
region.

The only forecast dilemma is with the timing of a cold front late
next weekend moving into the region. The 12z operational GFS is
the fastest...and most aggressive solution. However...deferred to
the slower European model (ecmwf) which has support from the gefs.

As for convection...the highest probabilities will be across the
interior where the airmass can destabilize the most. Most of the
activity is expected to be diurnal in nature outside of any weak
short wave energy able to sustain convection into the nighttime
hours. This will be a moderate cape environment...but weakly
sheared. Steering flow becomes light aloft at the end of the week.
Thus...localized heavy rainfall will be a possibility as well.

Potential for a more organized rainfall event late next weekend
as cold front moves into the area.

Conditions will remain unseasonably warm by about 5 to 10
degrees.

&&

Aviation /00z Tuesday through Saturday/...
high pressure remains east of the area for the next several days.

VFR through the taf period.

Wind south to southwest increases Tuesday morning to 10 to 15 knots and
by afternoon wind may be 15 to 20 knots sustained with gusts 20 to 25
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: southerly wind remains gusty until around 03z
this evening.

Winds at 750-1000 feet above ground level could be near 40kt until 07z.

Southerly wind will become gusty again Tuesday during the
afternoon...and may be a hour or two earlier than in forecast.

Klga fcster comments: there may be occasional gusts near 20 knots
through 02z this evening.

Southerly wind becomes gusty again Tuesday afternoon and may occur
an hour or so later than in the forecast.

Kewr fcster comments: southwesterly gusts may end before 03z this
evening.

Around midday south to southwest wind gusts increase once
again...190 to 210 true. Timing of the beginning of the gusts may be
later than in the forecast.

Kteb fcster comments: southerly wind gusts up to 20 knots develop late
in the afternoon. Gusts may develop an hour to two earlier than in
the forecast.

Khpn fcster comments: southerly wind gusts up to 20 knots develop late
in the afternoon. Gusts may develop an hour to two earlier than in
the forecast.

Kisp fcster comments: southerly wind gusts may end earlier this
evening...soon after 00z.

Winds at 750-1000 feet above ground level could be near 40kt until 07z.

Southerly wind gusts develop once again Tuesday afternoon...and may
begin an hour or two earlier than in the forecast.



Outlook for 00z Wednesday through Saturday...
Tuesday night...southerly wind gusts 20-25kt end early in the
evening. There is a low chance of some MVFR stratus along the
immediate coast of Long Island.

Wednesday...low chance of early morning MVFR stratus. Low chance
of afternoon and early evening shra/tstm...mainly north and west of
the NYC metropolitan terminals. Southerly wind gusts up to 25 knots.

Thursday-Saturday...this is a chance of late night and early
morning MVFR or lower stratus and/or fog. There is a low chance of
afternoon and evening shra/tstm. Wind gusts 20-25 knots.

&&

Marine...
extended the Small Craft Advisory on The Harbor and South Shore bays until 10pm
with gusts at JFK/ewr and buoy 44065 still above 25kt. These gusts
should fall below Small Craft Advisory levels late this evening.

No changes to the Small Craft Advisory on the ocean waters. Seas will build to 5
feet tonight and should remain above 5 feet through at least Tuesday
night. Winds may diminish below Small Craft Advisory levels late tonight through
Tuesday morning...but with the increased seas...will go ahead and
carry the Small Craft Advisory through Wednesday morning.

Dry conds tonight...and then scattered showers/thunderstorms possible Tuesday
night. Areas of fog will develop Tuesday night as well...possibly
reducing visibility to less than 1 nm.

Rough seas are likely to continue through the end of the due to a
persistent southerly around the western periphery of the sub tropopause ridge.

Fog will become more likely through the week...especially at night
and into the early morning.

&&

Hydrology...
scattered showers/thunderstorms possible Tuesday night through Wednesday
morning...and any training of cells could result in minor
urban/small stream flooding.

There is potential for a more organized rainfall event late next
weekend as cold front moves into the area.

&&

Okx watches/warnings/advisories...
CT...none.
New York...none.
New Jersey...none.
Marine...Small Craft Advisory until 6 am EDT Wednesday for anz350-353-
355.
Small Craft Advisory until 10 PM EDT this evening for anz338-
345.

&&

$$

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