000
FXUS61 KOKX 041109
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
609 AM EST Mon Dec 4 2023
.SYNOPSIS...
An area of low pressure across Northern New England today will
gradually weaken and push offshore by this evening. Weak high
pressure will then build in tonight through Tuesday, eventually
dissipating as low pressure develops well south and east of the
area on Wednesday. Weak high pressure returns for Thursday and
Thursday night. This high moves offshore Friday into the start of
the weekend. A strong frontal system approaches on Sunday.
&&
.NEAR TERM /THROUGH TONIGHT/...
-- Changed Discussion --
Any lingering fog and low clouds across southeast CT will
dissipate within the next 1-2 hours as west winds strengthen
and bring drier air into the area.
Weakening low pressure across northern New England today works
offshore by early this evening. This will keep the area under a
westerly flow, which will gust up to 20 mph at times. Multiple
shortwaves in the polar branch of the jet will work off the Mid
Atlantic coast in coming days. The first passes to the south
later this afternoon into tonight. While there will not be much
impact from this system, associated upper jet energy will allow
for an increase in mid and high clouds later this morning into
this afternoon with skies becoming mostly cloudy. A dry subcloud
layer should inhibit any precipitation, but perhaps a sprinkle.
Highs will top out in the upper 40s to lower 50s, which is few
degrees above normal.
For tonight, skies will clear in the evening with continued weak
cold advection behind the departing shortwave trough. Winds will
stay up enough to limit strong radiational cooling, with lows
generally in the 30s, right around normal.-- End Changed Discussion --
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY/...
Weak high pressure builds in from the west on Tuesday with a
diminishing NW flow and highs a few degrees below normal in the
40s. An amplifying shortwave trough across the Great Lakes and
Midwest on Tuesday tracks toward the eastern seaboard Tuesday
night and offshore on Wednesday. Once again, jet energy
associated with the trough will send some mid and high level
clouds back into the area Tuesday, persisting through much of
the period. Offshore low development takes place off the Mid
Atlantic coast late Tuesday into Wednesday, staying well south
and east of the forecast area. Guidance is depicting some light
precipitation Tuesday night and Wednesday along the New England
coast in a strengthening northerly flow. This is likely in
response to much colder air working across the warmer marine
waters. It`s possible that far eastern areas like SE CT and
eastern LI see a few rain and/or snow showers, but thinking is
this likely stays to the south and east. The bigger issue will
be much colder air arriving into the region with lows Tuesday
night generally at or below freezing except for the NYC metro,
with highs on Wednesday in the upper 30s to lower 40s. This is
about 5 to 8 degrees below normal.
&&
.LONG TERM /WEDNESDAY NIGHT THROUGH SUNDAY/...
A low develops off of the Carolina coast on Wednesday, by Wednesday
night it strengthens as it tracks east, out to sea. The increasing
pressure gradient to the south may lead to stronger winds for
southern portions of the CWA Wednesday night, decreasing into
Thursday as the low treks farther away.
Surface high pressure builds in from the southwest on Thursday with
a ridge aloft moving in from the west. This will help usher in
warmer air in low-levels with gradual warm air advection each
day into the start of the weekend. On Thursday, we will be in
the left exit region of a jet streak to our northwest then
transitions to the right entrance region of this jet streak as
it passes to our east on Friday. This increase in synoptic lift
along with periods of increased moisture in the low levels and
warm air advection will likely mean partly cloudy skies prevail
through Saturday, despite the building high pressure. Warm air
advection will help lift temperatures back to above average by
Friday/Saturday with highs in the upper-40s/low-50s on Friday
and in the low/mid-50s on Saturday.
A textbook Colorado low will develop over the Central Plains Friday
into Saturday before growing in size as it tracks Northeast. This
low will pass through the eastern Great Lakes with a strong cold
front along with it approaching from the west. This cold frontal
passage is expected late Sunday. Ahead of the cold front, you
can expect SW winds on Saturday to shift south on Sunday and
increase ahead of the front. This will also increase high
temperatures for Sunday, expected to be in the mid-50s. A line
of rain will pass along with the front late on Sunday with no
wintry precip currently expected due to the strong prefrontal
warming. Sunday night, after the frontal passage, some lingering
light precip is possible as temperatures begin to cool.
&&
.AVIATION /11Z MONDAY THROUGH FRIDAY/...
One low pressure system slowly lifts to the northeast this morning
as a weaker low moves offshore. Low pressure lingers over New
England today as high pressure slowly builds in from the west.
Flight categories have begun improving with many TAF sites back to
VFR or MVFR. Fog continues to clear out with clouds also breaking,
though still remaining inland. VFR is expected to prevail at most
terminals in the next few hours. No more rain expected.
Winds will continue to shift to the west this morning.
Wind speeds will gradually increase through the morning, becoming 10-
15 kt by afternoon. Gusts 17-20 kt are possible in the afternoon,
though looking less likely than in the previous TAF update, so have
removed gusts at most TAF sites. Winds shift to the WNW Monday night
around 10 kt or less.
...NY Metro(KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Timing of improving flight categories may be off by 1-2 hours.
Gusts may be occasional this afternoon.
OUTLOOK FOR 09Z TUESDAY THROUGH FRIDAY...
Monday Night-Tuesday VFR.
Wednesday: Mainly VFR. N-NW winds G15-20kt afternoon into night near
the coast.
Thursday-Friday: VFR.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90
&&
.MARINE...
SCA conditions develop in a strengthening westerly flow this
morning on the ocean waters. Generally looking at marginal
conditions through tonight with G20-25kt and seas of 3 to 5 ft.
Elsewhere, gusts will be closer to 20kt. High pressure builds
in Tuesday with decreasing winds and seas. Low pressure development
well south and east of the area late Tuesday night into Wednesday
will result in a strengthening northerly flow with the potential
for marginal SCA conditions developing Wednesday afternoon/night.
Mainly below SCA conditions forecast for all waters Thursday
through Friday. SCA conditions become more probable for ocean
waters Friday night with 5 foot waves currently forecasted on
the the eastern ocean zones.
&&
.HYDROLOGY...
No hydrologic impacts expected through the end of the week.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory until 4 AM EST Tuesday for ANZ350-353-355.
&&
$$
SYNOPSIS...BR/DW
NEAR TERM...DW
SHORT TERM...DW
LONG TERM...BR
AVIATION...BR
MARINE...BR/DW
HYDROLOGY...BR/DW