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Area forecast discussion 
National Weather Service New York New York
204 am EDT Tuesday Jun 2 2015

Synopsis...
waves of low pressure will track just to the south of the region
along a frontal boundary through Tuesday. High pressure builds in
Tuesday night. High pressure builds over the northeast as low
pressure develops over the southeast for the middle of the week. A
cold front moves through the area on Saturday and becomes nearly
stationary south of the area for the start of the new week.

&&

Near term /until 6 am this morning/...
showers continue to move across the region. However...radar
coverage has been decreasing as they make their way into the
area...which is in line with many of the mesoscale models.
Dewpoints were adjusted a bit lower...a testament to the drier air
working into the region. As a result...lowered quantitative precipitation forecast amounts
somewhat across the area. Also...took out mention of isolated
thunder as no lightning has been observed and the introduction of
the lower dewpoints means a less unstable atmosphere...despite
some elevated instability previously noted.

Despite the lower quantitative precipitation forecast amounts...00z sounding showed a precipitable water of 1.73
inches. This will continue the potential for locally heavy
rainfall and accompanying urban and poor drainage flooding. Some
smaller streams...especially in New Jersey...could also exceed bankfull.
Flash Flood Watch continues for all but eastern Li for this
threat. See Hydro section for more information.

&&

Short term /6 am this morning through 6 PM Wednesday/...
the northern stream upper low tracks through Quebec into northern
Maine during this time period. At the surface...the stalled front
to the south...with weak waves of low pressure tracking along
it...gradually gets pushed farther south as high pressure builds
in from the N/NW.

A transition to mainly stratiform rain and decreasing probability
of thunderstorms is expected from northwest to southeast late tonight through
Tuesday morning as low level jet and instability axis gets pushed farther
southeast. Frontogenetic/deformation bands of moderate to heavy rain
still expected with deep lift of the moist airmass. A general 1 to
3 inches of rain likely across the region tonight into Tuesday.
Flash Flood Watch continues for all but eastern Li for this
threat. See Hydro section for more information.

With abundant cloud cover...onshore flow and precipitation...temperatures will
be about 15 to 20 degrees below normal once again on
Tuesday...struggling to reach 60 degrees.

Gradually drying from northwest to southeast expected Tuesday afternoon into Tuesday
evening as Canadian high pressure builds into the region from the
north. Chilly conditions for June...with lows will about 5 to 10
degrees below normal Tuesday night.

There is a moderate risk for rip currents at ocean beaches of
southeast Suffolk County and a low risk for rip currents at ocean
beaches from New York City to southwest Suffolk County.

&&

Long term /Wednesday night through Monday/...
high pressure builds over the area on Wednesday and moves offshore on
Thursday. Meanwhile...frontal boundary remains nearly stationary
over the middle-Atlantic and southeast U.S. On Wednesday...and low pressure
will develop off the southeast U.S. Coast. As a result...can expect
a prolonged period of easterly flow for the middle-week period. Skies
will be cloudy...especially for coastal areas...and temperatures will fall
just below seasonal averages with highs in the upper 60s to low 70s.

With the high offshore on Friday...southerly flow develops ahead of
an approaching cold front. Low pressure off the southeast coast moves
offshore as well. Temperatures will warm up by a few degrees to close out
the work week. That front moves across the region on Saturday...and
likewise will become nearly stationary just south of the area for
the start of the new week. Scattered showers and thunderstorms will
develop with the passage of the front on Friday and Saturday.

Another low looks to develop on that boundary and impact the region
with rain for the start of the new work week.

&&

Aviation /06z Tuesday through Saturday/...
a frontal boundary remains across southern New Jersey and south of
Long Island with waves of low pressure moving along the boundary
into this afternoon. High pressure to the north begins to build
south late this afternoon...pushing the frontal boundary south. The
high builds to the north through Tuesday night.

Highly variable conditions expected today...varying from IFR
ceilings to marginal VFR ceilings...with visibilities varying from
VFR to IFR. Periods of light to moderate rain...and at times heavy
rainfall...continues into this afternoon. Rain ends early this
evening. Not expecting ceilings to improve Tuesday night as a
northeast flow will continue.

Wind will be from the northeast through the forecast...030 to 060
true...10 to 15 knots.

Low confidence in the forecast with uncertainty in the timing of
changing conditions.

Outlook for 06z Wednesday through Saturday...
Tuesday night...conditions improving to VFR late.
Wednesday-Thursday...VFR.
Friday...chance of showers with marginal VFR conditions.
Saturday...showers ending in the afternoon with conditions
improving to VFR.

&&

Marine...
a steady marginal Small Craft Advisory east/NE flow will continue through tonight
with seas of 4 to 7 feet on the ocean. Winds will gradually veer
and weaken Tuesday...with seas then gradually falling below Small Craft Advisory
levels Tuesday night as high pressure builds towards the waters.

Once seas fall below Small Craft Advisory levels Tuesday night into Wednesday....high pressure
over the waters will keep winds/seas below Small Craft Advisory levels through the
end of the week. A cold front will move across the waters this
weekend.

&&

Hydrology...
the Flash Flood Watch continues through 00z Wednesday for all but
eastern Li for urban/poor drainage flooding threat from any
training heavy showers and thunderstorms. A few flashy streams
and small rivers...especially in NE New Jersey...could exceed bankfull due
to the saturated grounds from rainfall over the last 36 hours.

Additional basin average quantitative precipitation forecast of 1 to 3 inches expected into Tuesday
evening before coming to and end.

The next chance for widespread precipitation will occur on Friday
and Saturday as a cold front moves across the region.

&&

Okx watches/warnings/advisories...
CT...Flash Flood Watch through this evening for ctz005>012.
New York...Flash Flood Watch through this evening for nyz067>075-078-080-
176>179.
New Jersey...Flash Flood Watch through this evening for njz002-004-006-
103>108.
Marine...Small Craft Advisory until 6 PM EDT this evening for anz350-
353-355.

&&

$$
Synopsis...mps/NV
near term...jp/NV/dw
short term...jp/NV/dw
long term...mps
aviation...jmc
marine...mps/NV
hydrology...mps/NV

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