000
FXUS61 KOKX 031208
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
708 AM EST Sun Dec 3 2023
.SYNOPSIS...
Deepening low pressure tracks across the eastern Great Lakes
today, with a secondary low developing to the south of the area.
Both lows lift north and east of the area tonight into Monday.
Weak high pressure returns for Tuesday. A wave of low pressure
develops off the Middle Atlantic coast Wednesday, passing well
south and east. High pressure returns for Thursday. The next
frontal system may move through the region next Friday or
Saturday.
&&
.NEAR TERM /THROUGH TONIGHT/...
Rain has overspread much of the area will become steadier over
the next few hours. Max amounts back to the south and west are
shy of a .1"/hr.
Guidance has been relatively consistent with this system as
rain overspreads the area this morning. A upper trough tracking
from the Mid Mississippi Valley this morning and into the
eastern Great Lakes by this evening will send a frontal system
and multiple waves of low pressure into the Northeast tonight.
The main surface low will follow a similar track as it quickly
occludes by this evening. A secondary low will form farther east
across the Mid Atlantic states this afternoon, passing just
south and east of the area this evening. Rain associated with
this system will primarily be from overrunning due to a
strengthening low-level easterly flow and a SW flow aloft. The
steadiest rain will be this morning into early this afternoon.
As the mid levels dry out this afternoon, the rain will likely
become lighter with areas of drizzle. Model time-height cross
sections are still showing decent lift in the low-levels this
afternoon due to the overrunning. So there could still be some
pockets of steadier rain due to warm rain processes.
As the upper trough become more open and weakens across the
eastern Great Lakes and Northeast tonight, it will send a
double-barreled low structure north and east of the area. There
could still be a pocket of steadier rain working from west to
east across the area this evening in association with the upper
vort.
Rainfall amounts for the event will average around 0.75".
Temperatures today will see little fluctuation from this morning
with highs in the upper 40s to lower 50s. This combined with
east winds gusting to around 20 mph at the coast will make for a
real raw day.
Behind the low tonight, east winds diminish and flip around to
the west toward midnight. Modest cold advection will follow,
but with winds and cloud cover to start lows will remain about
10 degrees above normal.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY/...
For Monday, expect west winds and highs in the upper 40s to
lower 50s. This is still a shade above normal. Another upper
trough passes to the south Monday afternoon/evening. This
combined with the weakening and stationary upper trough across
the Northeast and eastern Canada may produce enough mid and
upper level lift for a cloudy afternoon. This appears to be
driven by a coupling jet structure as one jet departs the
Northeast and another approaches from the SW. The subcloud layer
looks too dry at this time to support any precipitation.
Shortwave ridging aloft and a weak surface high build across
the area late Monday night into Tuesday. Temperatures during
this time will return close to normal with lows mainly in the
30s and highs in the 40s.
&&
.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
Another shortwave within the larger upper trough approaches
Tuesday night. The shortwave will help amplify the trough as
it pushes off the Middle Atlantic and southeast coast on
Wednesday. The modeling continues to be in good agreement that
the amplification will be too far east for any impacts from a
low pressure developing off the Middle Atlantic coast. Have left
in a slight chance PoP Tuesday night for southern portions of
Long Island and extreme southeast Connecticut based on the model
consensus, but any precip would largely be isolated. Colder
temperature profiles would support some brief wet snow with
potentially some rain mixed. These PoPs may need to be trended
down in subsequent forecasts and conditions may stay dry Tuesday
night and Wednesday given latest model trends.
The upper trough moves offshore Wednesday night into Thursday with
heights rising into next weekend. High pressure returns on Thursday
and may give way to a frontal system next weekend. The associated
energy and shortwave passes well to our north, so have kept the
forecast dry for now. The main theme heading into the end of
the week and next weekend will be temperatures trending back
above normal by next Saturday.
&&
.AVIATION /12Z SUNDAY THROUGH THURSDAY/...
-- Changed Discussion --
Weak low pressure system slowly approaches from the southwest
today with the primary low reaching the eastern Great Lakes and
a secondary low developing to the south of the area. The Great
Lakes low tracks northward this evening while the offshore low
moves east.
Some minor improvements over the last few hours, with
widespread IFR conditions being reported. KGON continues to
remain VFR, but is expected to drop to MVFR or lower by around
15Z. IFR conditions are expected to continue, with occasional
LIFR conditions possible at times. Improvement to MVFR is
expected tonight. Again, timing remains uncertain, with
uncertainty as to how much ceilings and visibilities improve.
Conditions improve to VFR around 07Z Monday.
Winds will be generally light and variable until a light NE flow
develops, and strengthens somewhat this morning. As the lows move
over the region this evening winds become light and variable
again. And with the low moving north tonight winds become
westerly.
...NY Metro(KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Amendments expected with rain and changing flight categories, but
should generally be IFR most of the day today. Improvement to MVFR
possible late in the day as rain tapers off. An occasional gust to
around 15-20 kt possible in the morning, to around midday.
OUTLOOK FOR 12Z MONDAY THROUGH THURSDAY...
Monday: VFR. W winds G15-20kt, becoming more NW at night.
Tuesday: Mainly VFR.
Wednesday: Mainly VFR. N-NW winds G15-20kt afternoon into night.
Thursday: VFR. NW winds G15-20kt.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
A strengthening easterly flow this morning will bring SCA
conditions to the ocean waters, eastern LI sound, and the
eastern and southern bays of LI. Winds will then diminish by
this evening and winds will flip around to the W by midnight.
SCAs will remain up for the ocean even with the lull as seas
will be right around 5 ft. However, west winds increase with
gusts up to 25 kt on the ocean waters by daybreak Monday.
Marginal SCA conditions could linger on the ocean through Monday
night. Weak high pressure then follows for Tuesday with sub-SCA
conditions.
Sub-SCA conditions expected on all waters Tuesday night through
Friday with a weak pressure gradient. There is a chance for winds to
reach SCA criteria on the ocean waters Wednesday night as low
pressure well east of the area strengthens.
&&
.HYDROLOGY...
Rainfall totals today will mainly be around 0.75 inches. No
hydrologic impacts expected through next week.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
-- Changed Discussion --
CT...None.
NY...None.
NJ...None.
MARINE...Small Craft Advisory until 6 PM EST this evening for ANZ331-
332-340-345.
Small Craft Advisory until 6 PM EST Monday for ANZ350-353.
Small Craft Advisory until 4 PM EST Monday for ANZ355.-- End Changed Discussion --
&&
$$
SYNOPSIS...JP/DW
NEAR TERM...DW
SHORT TERM...DW
LONG TERM...JP
AVIATION...JP
MARINE...JP/DW
HYDROLOGY...JP/DW