561
FXUS61 KOKX 301922
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
322 PM EDT Fri Aug 30 2024
.SYNOPSIS...
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High pressure retreats to the northeast tonight as a warm front
approaches late tonight into Saturday. A cold front pivots through
late Saturday night into Sunday. A secondary cold front moves
through late Sunday into Sunday night. Thereafter, high pressure
builds in from the Great Lakes region and will remain in control
through the middle of next week, gradually moving offshore late
next week.-- End Changed Discussion --
&&
.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
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High pressure should maintain itself for the most part down the New
England coast and into at least eastern portions of the area
tonight. A warm front back to the west and southwest will be held
back as the surface high and mid to upper level ridging should keep
the region primarily dry through the night. A fair amount of cloud
cover will persist, more so across the western half of the area
initially. Then later tonight as the high starts to lose its
influence more cloud cover overall gets into eastern portions of the
area. A light onshore flow will continue, thus with the onshore flow
and cloud cover this should put a floor on how much temperatures can
drop tonight. Temperatures should hold near seasonable levels with
little spread, with lows in the 60s.-- End Changed Discussion --
&&
.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
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Whatever is leftover of mid level ridging should hold through the
first half of the day keeping the region dry. A warm front should be
draped across PA and the southern tier of NY during the morning. The
warm front should gradually make its way east into the afternoon and
early evening. Some showers are likely to develop to the northwest
later in the day. Towards evening the chances of shower activity
should increase across NW sections. Partial sunshine is expected for
much of the day, with more clouds, especially further west in the
afternoon. A S to SSE flow will have dewpoints increase into the
middle and upper 60s adding more humidity. Temperatures will be near
seasonable levels, but becoming more humid with day time highs in
the upper 70s to lower 80s. As the area gets into the warm sector
instability begins to increase further west late in the day and
towards evening. PWATs begin to climb above 1.5, and eventually get
closer to 2 inches into the evening. With a more humid environment
the chance of showers increase from west to east out ahead of a cold
front for Saturday evening. Some steadier rainfall, especially
across the western half of the CWA becomes more likely later
Saturday night. Some embedded heavier showers will be possible with
any thunderstorms that form. BUFKIT soundings for the NAM3km and
RAP, GFS are indicating some CAPE Saturday night. For more rain
detains see the hydrology section. SPC has a marginal to slight risk
of severe weather mainly for the Saturday evening / night period,
with the risk decreasing eastward. A more general thunderstorm
category has been placed across eastern sections. It is likely, at
least initially during Saturday night that the instability will be
more elevated, with more sfc based instability likely waiting until
later in the weekend. The stronger mid level forcing appears to be
lagging a bit back to the west, at least during the first half of
Saturday night.-- End Changed Discussion --
&&
.LONG TERM /SUNDAY THROUGH FRIDAY/...
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A well-defined secondary cold front arrives late on Sunday and
manages to push through Sunday evening and early night.
A line of showers and thunderstorms will pass along and ahead of the
front, clearing out early Sunday night. Sufficient moisture (max
PWATs around 2 inches), warm temperatures (highs in the low/mid-
80s), and ample instability (SBCAPE peaking around 1000-2000 J/kg)
will allow for a good environment for thunderstorms that could lead
to an occasional downpour. However, bulk shear appears to be lacking
with peak values around (20-30 kt), so the only concern severe
weather concern may be an isolated instance or two of strong to
damaging winds along the cold front where the greatest amount of
forcing and lift will be present. SPC has highlighted a Marginal
Risk for the area on Sunday.
Following the cold front Sunday evening/night, winds will turn from
south to northwest, advecting cooler, drier air into the area.
Dewpoints will drop through Sunday night and continue to do so
through the day on Monday. With strong cold air advection aloft at
850 mb and a steady northwest wind, highs on Monday will be limited
to the low/mid-70s with a few reach the upper-70s.
High pressure will continue to build in behind the exiting front
from the Great Lakes region on Monday and Tuesday, leaving a very
sunny forecast for early next week. Overnight lows will drop into
the upper-40s to upper-50s north-to-south Monday night. Dewpoints
drop into the 40s Monday night and remain there through Tuesday
night, reinforced by northwest flow. This will lead to conditions
feeling cool and crisp during the nights and pleasant in the
afternoons with highs in the mid/low-70s on Tuesday.
Most model guidance brings the high pressure overhead on Wednesday,
then gradually push it offshore Thursday and Friday. This will lead
to a return flow from the southerly. High pressure will firmly
remain in place on Wednesday and still mainly in control on
Thursday, allowing for more cloud-free days, before cloud cover
increases as the high exits east Thursday night into Friday.
Southerly winds will lead to increasing temperatures and dewpoints
late next week. HIghs will be in the mid-70s to low-80s by Friday.
Most global models try to develop a coastal low along the mid-
Atlantic coast Friday and bring it near the CWA Friday night into
Saturday, but this is still very far out and the models do differ in
strength, placement, and timing.-- End Changed Discussion --
&&
.AVIATION /19Z FRIDAY THROUGH WEDNESDAY/...
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High pressure extends into the area from the east today and
weakens tonight.
VFR during the daytime, lowering to MVFR tonight. VFR returns
late Sat morning into early afternoon.
E winds around 10kt bcmg ESE-SE tonight under 10kt. Winds veer
further SE-SSE on Saturday, returning to around 10kt.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Time for cigs returning to MVFR tonight may be off by a few
hours. Winds may vary NE to E at KLGA late this afternoon.
OUTLOOK FOR 18Z SATURDAY THROUGH WEDNESDAY...
Saturday PM: VFR. Iso tstm with brief MVFR possible NW of the
city.
Sunday: MVFR/IFR with a chance of showers in the morning. VFR in
the afternoon with iso shower/tstm possible.
Monday through Wednesday: VFR.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
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Winds and waves will remain below SCA criteria through Saturday
night, and also should remain below SCA criteria through the
middle of next week. There could be a period of occasional 25 kt
gusts this weekend and on Monday with two cold frontal
passages, but this remains a low probability at this time.-- End Changed Discussion --
&&
.HYDROLOGY...
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Any hydro related impacts over the weekend appear fairly minimal at
this time. There remains the possibility of minor flooding in poor
urban drainage locations with any heavier showers across mainly
for the western half of the CWA towards Saturday night. WPC
maintains a marginal risk of excessive rainfall across a good portion
of the CWA.-- End Changed Discussion --
&&
.TIDES/COASTAL FLOODING...
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There is a moderate risk for rip currents along NYC and Nassau
county beaches on Saturday. All Long Island ocean beaches will have
a moderate risk for rip currents on Sunday.-- End Changed Discussion --
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...None.
&&
$$
SYNOPSIS...JE/BR
NEAR TERM...JE
SHORT TERM...JE
LONG TERM...JC
AVIATION...JC
MARINE...JE/BR
HYDROLOGY...JE/BR
TIDES/COASTAL FLOODING...