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fxus61 kokx 280802 
afdokx

Area forecast discussion
National Weather Service New York New York
402 am EDT Fri Apr 28 2017

Synopsis...
a series of weak fronts cross the region Friday through Saturday
night. High pressure moves to the north of the region Sunday,
shifting east by Monday with a warm front moving northward
through the area by afternoon. A cold front moves through Monday
night, followed by weak high pressure through Wednesday. A
frontal system approaches from the southwest Thursday and moves
along the coast through late week.

&&

Near term /until 6 PM this evening/...
fog, locally dense, should burn off an hour or so after sunrise
this morning. A weakening cold front will cross the region and
continue to weaken as it does so. Only slight chance for showers
through early this morning, then dry conditions return. There
may be a rumble of thunder, but not confidence is low.

Temperatures will be on the warm side with a downsloping
offshore northwest flow, shifting to the southwest by the
afternoon. Temperatures away from the coast will reach the upper
70s to lower 80s, warmest across northeast New Jersey. Coastal
sections will be cooler with the potential for local sea
breezes.



&&

Short term /6 PM this evening through 6 PM Saturday/...
much of Friday night should remain dry and warm. Lows will only
fall to the 50s to lower 60s. A cold front will approach from
the northwest, giving the area a chance for showers, mainly just
before sunrise Saturday morning. Of particular concern is the
00z NAM, which looks to spin up an mesoscale convective system. Not totally bought into
this, but needs to be monitored with further model runs.

The cold front should push through late in the afternoon,
however, any lift with this front weakens in the afternoon, so
just a passing shower or thunderstorm is possible away from the
coast. Coastal areas may not see any activity in the afternoon
as marine influence keeps the atmosphere more stable here.
Temperatures will be even warmer on Saturday than Friday, with
highs in the upper 70s (even along much of the coast) to middle
80s (mainly in the New York City Metro area). The Twin Forks of
Long Island and southeast Connecticut will see highs in the
upper 60s to lower 70s.

&&

Long term /Saturday night through Thursday/...
by Sunday, an upper ridge centered off the southeast coast will
build northward leading to a strengthening subsidence inversion
across the area. Although there will be elevated instability, the
strengthening inversion, in part due to low-level onshore flow, and
lack of overall forcing for ascent should generally limit
precipitation/thunderstorm chances. Onshore flow and cloud cover
will limit heating, keeping temperatures near or slightly below
climatological normals during the daytime, and slightly above normal
for night. Onshore flow will continue into Monday morning, likely
saturating lower levels and leading to increasing chances of light
rain and/or drizzle. Went with a slightly slower European solution
regarding the warm frontal passage, keeping the area cooler and
cloudier for the earlier part of the day. The front should gradually
move northward by afternoon or perhaps evening, with south flow
leading to above normal temperatures across inland areas away from
marine influence, and near normal elsewhere. The cold front moves
through Monday night with likely rain and a chance of thunderstorms,
giving way to clearing skies, gusty west winds and seasonable
temperatures by Tuesday afternoon. Gusty west flow will continue
into Wednesday, with cold advection offset somewhat by downsloping.
Went slightly above guidance for Wednesday due to downslope
component of the winds and lack of expected marine influence. By
late week, a deepening area of low pressure will approach from the
south with increasing chances of rain late into the work week.

&&

Aviation /08z Friday through Tuesday/...
a weakening cold front dissipates as it moves into western
portions of the area this morning. High pressure then builds in
from the southeast into tonight.

IFR or lower at all terminals this morning, falling beneath
terminal minimums at times. Conditions should improve around 10z
far west/12z city terminals/14z eastern terminals to IFR-MVFR as
flow becomes more SSW-SW, then VFR by mid morning to early
afternoon from W to E as well.

Light and variable/E-se flow under 10 kt, gradually veers to
west over western terminals by mid morning and to the SW at eastern
terminals by around midday. Seabreezes likely at CT terminals
and possible at Long Island/City terminals this afternoon.
Frequent gusts to around 15 kt are possible this afternoon
kewr/kteb/khpn, with occasional gusts to 15 kt possible at
remainder of city terminals. Winds become light and variable
again this evening at all but kjfk and klga - where south-southwest-SW at
under 10 kt.

Outlook for 06z Saturday through Tuesday...
late tonight-Saturday morning...isolated-scattered showers
with embedded thunderstorms are possible.
Saturday afternoon-Sunday...VFR.
Sunday night-Monday...MVFR or lower possible.
Monday night...MVFR possible along with isolated to scattered
showers and thunderstorms isolated thunderstorms.
Tuesday...VFR.

&&

Marine...
dense fog early this morning will burn off by mid-morning.
Scattered showers with an isolated thunderstorm will affect the
ocean zones over the next couple of hours.

Winds and seas will remain fairly tranquil on Sunday, though
isolated gusts to 25 kt will be possible during the afternoon and
early evening. As winds become more southerly and increase on Monday
ahead of an approaching cold front, seas will build to 5 to 9 ft
Monday night. Ocean seas will linger over 5 ft into Tuesday and
Wednesday as flow becomes more westerly but remains strong, with
gusts to 25 kt possible, mainly during the afternoon and evening.
Seas will briefly diminish Wednesday night into Thursday as weak
high pressure moves though, before increasing again Thursday night
ahead of an approaching area of low pressure.

&&

Hydrology...
no widespread hydrologic impacts foreseen through the next 7
days.

&&

Okx watches/warnings/advisories...
CT...none.
New York...none.
New Jersey...none.
Marine...dense fog advisory until 10 am EDT this morning for anz330-335-
338-340-345-350-353-355.
Small Craft Advisory for hazardous seas until 2 am EDT
Saturday for anz350-353.
Small Craft Advisory for hazardous seas until 6 PM EDT this
evening for anz355.

&&

$$
Synopsis...MD/jp
near term...jp
short term...jp

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