233
FXUS61 KOKX 111923
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
323 PM EDT Fri Oct 11 2024
.SYNOPSIS...
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High pressure will reside south of the area tonight. A cold front
swings through Saturday and stalls to the south Saturday night. The
front lifts north as a warm front late Sunday into Sunday night
along with developing low pressure. The low drags a cold front
through Monday morning into Monday afternoon, with high pressure
slowly building in thereafter.-- End Changed Discussion --
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
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An old frontal boundary - sfc trough lingers nearby for awhile
tonight before getting further offshore late. Mainly clear skies are
expected with deep layer WNW flow. A light WSW flow closer to the
sfc gets established as the night progresses ahead of a cold front
which starts to approach getting closer to daybreak. With some weak
low level warm advection not expecting temperatures to get as cool
as previous nights as dew points get into the middle 40s for the
most part. This puts a floor on how much temperatures can fall. Any
cloud cover tonight will be high up and quite thin as latest
guidance has less in the way of cirrus compared to previous
guidance. Lows be in the lower and middle 50s along much of the
coast, with some upper 50s in the metro. Some upper 40s and lower
50s are expected in far northern and northwestern outlying locales.
A good start to the weekend is expected despite the fact that a cold
front begins to push through primarily for the morning. A shortwave
across the Northern Great Lakes region will dive across and clip
Northern New England early in the morning. This shortwave passes far
enough to the north that this will be a dry frontal passage with
virtually no moisture for the front to interact with. As a matter of
fact there should not even be much in the way of cloud cover with
the front. Perhaps only a few upper level clouds that may only
slightly filter the sunshine for a time. Otherwise, a mostly to
partly sunny day will be on tap. Temperatures should average a few
degrees above normal as temperatures should reach the lower half of
the 70s across a majority of the area, with perhaps a few upper 60s
to the NW.-- End Changed Discussion --
&&
.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY/...
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During Saturday night the cold front that pushes through earlier on
Saturday is expected to stall across the Mid Atlantic states. The
next shortwave feature on deck for late in the weekend will still be
back over the Northern Rockies for Saturday and moving across the
Northern Plains and portions of the Midwest Saturday night. That
will leave the region in-between a trough exiting the northeast, and
the approaching shortwave over the Midwest. Some higher level
clouds, and perhaps some mid levels clouds start to gradually work
in during Saturday night. Across the majority of the region it will
remain dry. However, across far NW portions of the area (Orange
County) start slight chance PoPs late with weak positive vorticity
and thermal advection. Low pressure develops in the Ohio Valley late
at night and into Sunday morning. This will lead to the frontal
boundary lifting north as a warm front into the day on Sunday. The
difficult part of the forecast pertains to whether there will be
enough in the way of some mid and high level clouds to prevent frost
formation across northern and northeastern portions of the region.
The winds will be light, but the amount of cloud cover is a bit
uncertain. For now thinking there will not be frost formation as the
air mass will likely not be cold enough, but some isolated frost
cannot be completely ruled out across northern most portions of CT
and the Hudson Valley. Lows are progged to be in the upper 30s and
lower 40s along the northern periphery of the CWA, otherwise 40s and
lower 50s in most places.
Low pressure develops further to the west Sunday morning and lifts
to the N and NE into Sunday afternoon and evening. This should drag
the stalled boundary to the south north as a warm front. A lot of
the upper level support will lag back to the west and get aimed
north of the area. Thus, likely PoPs will be reserved for
northwestern portions of the area, with chance PoPs getting further
south and east for the later morning and afternoon on Sunday. Any
rain / shower activity is expected to light. Rainfall amounts
through the day Sunday will around or just above a tenth of an inch
across far northwestern sections, with just a few hundredths
elsewhere. Some places along the southern periphery of the CWA may
not getting anything measurable through the day on Sunday. A mostly
to partly cloudy day is anticipated, with the relatively more clouds
and a higher chance of showers the further north and west one is.
Temperatures will range from near 60 across far northern areas where
there is more cloud cover, to the upper 60s and a few lower 70s
across far southern portions of the area.-- End Changed Discussion --
&&
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
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Sunday evening starts out with a deepening upper level trough
approaching from our west. The associated surface low at that time
should be centered somewhere over western PA, with its warm front
extending just north of our area or over northern portions of the
area. The low will deepen as it approaches and will likely pass just
over or near the area early Monday morning. Its cold front then
passes through later Monday morning into the afternoon, ushering in
the coolest airmass of the season.
In terms of weather, this system will bring rainy and windy
conditions. There is still some spread across the guidance, but
general consensus has the most likely period of rain being Sunday
night. PoPs don`t end until Monday night with the chance for some
lingering rain through the day on Monday and the possibility of the
front moving through later. With some instability available and
strong lift, thunder can not be ruled out and have added to the
forecast for Sunday night. The heaviest totals will likely be well
north of the area, with an average total of a few tenths for us.
Amounts will be locally higher in any thunderstorms. We could see
some gusty southerly winds ahead of the frontal passage, but the
stronger winds likely come later on Monday behind the front with
cold advection in a W/NW flow. Even mixing down winds from halfway
up the model mixed layer supports gusts in the mid to upper 20 kts.
Blended in NBM 90th percentile gusts to show this. The gust forecast
could continue to trend up.
Dry conditions expected thereafter, with high pressure very
gradually building in. Gusty conditions could continue as the
pressure gradient remains relatively tight. Dewpoints drop to the
low to mid 30s by Monday night and likely stay there through the end
of the week. While the winds remaining elevated do not support
radiational cooling, the cool airmass itself will bring lows in the
mid 30s to low 40s for the rest of the week. This is well below
average for early October.-- End Changed Discussion --
&&
.AVIATION /20Z FRIDAY THROUGH WEDNESDAY/...
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High pressure continues over the terminals. A cold front approaches
tonight and moves through on Saturday.
VFR through the TAF period.
WNW winds remain near 10 kt shifting to the W then WSW to SW into
this evening with some occasional gusts 15-20kt. Winds then shift
back to the NW Saturday morning at 10 to 15 kt after the frontal
passage becoming gusty in the afternoon, 20-25 kts. LLWS may occur
late tonight, between 06Z to 12Z, at 030 at 40-45 kt at or just
below 2 kft.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
No unscheduled amendments expected. Onset of gusts Saturday may be
off +/- an hour or so.
OUTLOOK FOR 18Z SATURDAY THROUGH WEDNESDAY...
Saturday afternoon: VFR. NW winds around 10kt, G15-20kt.
Saturday night: VFR.
Sunday: VFR for much of the day, SE / S winds G15-20kt in the
afternoon. Chance of showers with possible MVFR late and mainly at
night.
Monday: Mainly VFR, brief MVFR possible early in showers. W to NW
winds 10 to 15 kt, with gusts 15 to 20 kt.
Tuesday and Wednesday: VFR. NW winds.
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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Small craft conditions develop on the ocean waters this evening on a
W to NW wind. Marginal small craft conditions are likely for the
eastern half of LI Sound late tonight and through the morning. Small
craft conditions on the ocean should continue through the midday for
the western half of the ocean, and until late afternoon for the
eastern ocean waters as a NW wind will diminish during the afternoon
hours from west to east. Winds and seas will briefly remain below
small craft criteria Saturday night into early Sunday morning.
The pressure gradient will tighten once again late Sunday bringing
an extended period of Small Craft Advisory conditions on the ocean
waters and potentially all other waters. 25 kt gusts could start as
early as Sunday evening ahead of the cold front. On Monday behind
the cold front, 20 to 30 kt gusts are possible on all waters. 25 kt
gusts could then linger on the ocean waters through Wednesday night.
The prolonged period of windy conditions will also cause seas to
reach 7 to 8 feet by Sunday night and remain elevated through Monday
night. Sub Small Craft Advisory conditions expected by the end of
next week.-- End Changed Discussion --
&&
.HYDROLOGY...
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There are no hydrologic concerns through the forecast period.-- End Changed Discussion --
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
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CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory from 10 PM this evening to 4 PM EDT
Saturday for ANZ350-353.
Small Craft Advisory from 10 PM this evening to noon EDT
Saturday for ANZ355.-- End Changed Discussion --
&&
$$
SYNOPSIS...JE/JT
NEAR TERM...JE
SHORT TERM...JE
LONG TERM...JT
AVIATION...DR
MARINE...JE/JT
HYDROLOGY...JE/JT