870
FXUS61 KOKX 020337
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
1137 PM EDT Tue Oct 1 2024
.SYNOPSIS...
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High pressure slowly moves farther northeast from the region
through tonight. A weak cold front approaches on Wednesday and
dissipates west of the area. High pressure builds on Thursday
and remains in control through Friday. A weak cold front will
pass through the area sometime on Saturday followed by high
pressure to end the weekend. A stronger cold front looks to move
through early next week.-- End Changed Discussion --
&&
.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
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Forecast remains on track. Minimal changes made to cloud
coverage as well as temperatures and dewpoints. Min temperatures
slightly increased with expansive clouds moving across.
At the surface, high pressure remains well to the north across
eastern Canada while developing low pressure was located well to
the south off North Carolina. That places the region between
systems under a predominately easterly/northeasterly flow, with
shallow moisture trapped under an inversion.
Dry conditions are expected into the overnight, though an isolated
sprinkle cannot be completely ruled out across the far northwest
zones. The extensive clouds will keep lows tonight a bit warmer,
in the 50s to low 60s. Elsewhere in CT and the Lower Hudson
Valley, with lighter winds and dewpoints in the 50s, some good
radiational cooling may allow minimum temperatures to approach
the dewpoint by early Thursday.-- End Changed Discussion --
&&
.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/...
High pressure to the northeast sags a bit southward while the low to
our south heads further east. Another weak mid level shortwave
approaches from central PA by Wednesday morning, allowing a weak
cold front to approach from the northwest by afternoon. While the
front looks to stall and/or dissipate to the west, another day of
partly to mostly cloudy skies are in store with no real change in
airmass. Midlevel dry air remains in place and so low confidence in
any shower activity making it far enough east by Wednesday
afternoon. Highs will be similar to Tuesday, seasonable, in the mid
60s to near 70.
&&
.LONG TERM /THURSDAY THROUGH TUESDAY/...
Surface high pressure will build over the region on Thursday with
heights building aloft from a building ridge. This will lead to
warmer temperatures with highs in the low/mid-70s under mostly sunny
skies.
High pressure at the surface (with a weakening ridge aloft) remains
in control to start the day Friday, but at this point it is exiting
east giving way to a weak trough from the Great Lakes. A surface low
with a cold front is likely to develop just to our north along the
passing trough, but most forcing including positive vorticity
advection associated with the trough will be focused to our north.
Only a few light showers are possible (but unlikely) for northern
interior locations along the weak frontal passage Friday night into
Saturday morning.
Following the weak low and frontal passage, high pressure will
settle in for most of the weekend leading to mostly sunny skies and
continually warmer temperatures on Saturday with highs in the
mid/upper-70s.
Things change late on Sunday. High pressure weakens as an upper-low
and shortwave deepen over the Great Lakes. This low and associated
frontal system approach the area on Sunday and will likely impact us
late Sunday through Tuesday. First, a warm front will move in ahead
of the cold front late Sunday which will increase cloud cover and
moisture. PWATs currently peak around 1.5-1.6" among global guidance
Sunday night. Then the low will move over the area or just north of
us, bringing a cold front Sunday night/Monday morning (timing
subject to change given variance in global guidance). A line of
showers is likely to develop along the cold front given ample
moisture and forcing.
Following the frontal passage, things get a little tricky in the
Monday-Tuesday timeframe. Guidance varies on what happens with the
low when it passes us. Some guidance, such as the 12Z GFS deepen the
low over over area on Monday then linger it just off the New England
coast through Tuesday. Should this solution come to pass showers
could persist into Tuesday along with reinforced northerly flow and
lower heights aloft leading to temperatures becoming cooler than
currently forecast. However, other guidance, such as the 12Z ECMWF,
keep the low on an eastward trajectory followed by high pressure,
leading to a sunnier and drier Tuesday.
Regardless of which solution comes to pass, two things are likely.
Showers along a frontal passage followed by cooler air under
northerly flow. Highs on Monday are forecast in the low to upper-60s
followed by the mid/low-60s on Tuesday with overnight lows in the
mid-40s to mid-50s.
&&
.AVIATION /04Z WEDNESDAY THROUGH SUNDAY/...
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High pressure slowly shifts farther northeast of the region
during the TAF period with a cold front eventually approaching
from the west.
Mainly VFR initially but MVFR stratus develops and moves in
through overnight, lasting into Wednesday morning. Some
localized IFR will be possible early Wednesday morning. Lower
stratus expected to scatter out Wednesday afternoon with a
return to VFR.
Winds will be overall an easterly flow near 5-10 kt during the
TAF period.
NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
MVFR may be more intermittent overnight into Wednesday morning.
Start and end time of MVFR could vary a few hours from TAF.
OUTLOOK FOR 00Z THURSDAY THROUGH SUNDAY...
Wednesday Night through Friday: Mainly VFR.
Saturday: Mainly VFR. A slight chance of showers with MVFR possible.
Sunday: Chance of showers at night with MVFR possible.
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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As the surface low to the south continues to slowly head east,
expect the elevated seas to continue for the first half of
Wednesday. Thus, the SCA remains for the ocean through 19Z
Wednesday, with winds around 20kts but seas around 5 ft
continuing.
Sub SCA conditions are likely on all waters through the weekend.
There is potential for 25+ knot gusts and 5+ ft seas with a cold
frontal passage early next week.-- End Changed Discussion --
&&
.HYDROLOGY...
No significant hydrologic issues are expected through the middle of
next week.
&&
.TIDES/COASTAL FLOODING...
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Astronomical tides will be increasing with the approach of a
new moon Wednesday afternoon. This combined with a persistent
easterly wind may push levels right up to minor flooding
benchmarks for the Wednesday morning high tide cycle. A
statement may eventually be needed to address this for the south
shore back bays of Nassau and Queens.-- End Changed Discussion --
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory until 3 PM EDT Wednesday for ANZ350-353-
355.
&&
$$
SYNOPSIS...DBR/BR
NEAR TERM...JM/DBR/BR
SHORT TERM...DBR
LONG TERM...BR
AVIATION...JM
MARINE...DBR/BR
HYDROLOGY...DBR/BR
TIDES/COASTAL FLOODING...