000
FXUS61 KOKX 111440
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
1040 AM EDT Sun Apr 11 2021

.SYNOPSIS...
A weak warm front approaches this morning and becomes nearly
stationary southwest of the area through the middle of next week.
High pressure strengthens over the area for the end of the week.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Visibilities have improved overall due to rain moving in from
the south and southwest, along with the diurnal factors. Dense
Fog Advisories have thus been allowed to expire, although a few
pockets of localized lower visibilities for a couple of more
hours across some eastern sections before the rain arrives.

A weakening warm front approaches from the southwest in
association with weakening stacked low over the mid- West. This
warm front looks to stall southwest of the area this afternoon
as high pressure builds in from the northeast. As the front
weakens, the widespread rainfall will become more showery in
nature.

Cooler conditions expected today with clouds and rain. Highs will
only reach the upper 50s, with a few spots flirting with 60.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM MONDAY/...
With the warm front remaining to the south, the chance for
precipitation will continue tonight. Despite weakening lift at the
surface, candidness aloft become unstable, with upwards of 500 J/kg
of CAPE in some of the forecast soundings if lifting from 850-800
hPa instead of the surface, and continued mention of the chance for
thunder tonight. However, eastern portions, mainly across southern
Connecticut, look to be more stable than the rest of the forecast
area, as building high pressure stabilizes the atmosphere even
aloft, therefore, did not mention thunder for these areas. The
chance for thunder decreases through the night, with only a slight
chance expected after midnight. Locally heavy rainfall is possible
in any thunderstorm. However, flash flooding and severe weather are
not expected.

With the warm front remaining in the vicinity and cyclonic flow
aloft as the upper low over the mid-West finally moves east over
Pennsylvania, the chances for showers continue for Monday.
Conditions continue to cool for Monday, as the high pressure
continues to build in from eastern Canada. Temperatures will only
reach the lower 50s.

&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
A stalled frontal boundary invof the cwa will provide a focus
for periods of rain/shwrs thru the middle of the week. The most
organized activity continues into Tue, where dpva and
mid lvl frogen will be best. It is a little too far out to have
high confidence in where the best bands of pcpn develop, so pops
were capped at likely. The focus based on the 12z model
consensus is the wrn half of the cwa, but again with a nw-se
orientation, it will not take much to move to the band to
another portion of the fcst area or outside of the cwa
altogether.

A downward trend in pcpn chances for Wed into Thu. Still a roughly
20-40 pop thru the period with the lingering h5 low yielding decent
lapse rates and cyclonic flow aloft. High pres ridges across the
region Fri and Sat, ending chances for pcpn. NBM pops still lingered
slight chances for Thu, which were accepted for now until it becomes
clear that the h5 low will have indeed exited by then.

Thicknesses are pretty low for Tue and Wed, but the bl is modeled to
be too warm for any snow for most of the area. Perhaps portions of
the interior could see some flakes where lift is maximized.
Elsewhere, some IP possible in the area of strongest lift.

The NBM was used for temps for now. However, if confidence increases
in the Tue/Wed time period, highs will likely need to be dropped
about 10 degrees or so.

&&

.AVIATION /15Z SUNDAY THROUGH THURSDAY/...
A warm front approaches from the southwest through this morning,
then becomes nearly stationary this afternoon into tonight.

Ceilings remain IFR to LIFR with visibilities having improved
as the showers moved into the terminals from the southwest.
Ceilings will continue to gradually improve, but remain at IFR.

Scattered showers then remain in the area for the entire TAF
period with a low chance of thunder later this afternoon and
evening, especially at and west of the New York City terminals.
Chance of occurrence and confidence in thunder occurring is low
so it is not included in the TAFs as of now.

Easterly winds increase up to 10 kt through the morning and
10-15 kt this afternoon.

 ...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...

Amendments likely for category changes through this morning and
timing of precipitation.

.OUTLOOK FOR 12Z MONDAY THROUGH THURSDAY....
.Monday...A chance of MVFR and showers, mainly during the day.
.Tuesday-Wednesday...Mainly VFR with a slight chance of showers
.Thursday...Periods of MVFR possible early, otherwise VFR. Light N-
NE winds.

Detailed information, including hourly TAF wind component forecasts,
can be found at: http:/www.weather.gov/zny/n90

&&

.MARINE...
A dense fog advisory is in effect through 16Z. Showers and
turbulent mixing will then help improve the visibility shortly
thereafter.

Otherwise winds and seas remain under SCA levels through the
early afternoon as high pressure offshore drifts east. A
strengthening easterly flow will allow for ocean seas to build
to near 5 feet by late this afternoon and wind gusts may be near
25 KT. Ocean winds and seas likely remain above SCA levels
through Monday and possibly early Tuesday. A SCA has been issued
from late this afternoon through Monday. The non-ocean waters
are expected to remain below advisory levels.

Small craft cond will persist on the ocean Mon and Mon ngt. Winds
will be mrgnl on the protected waters Mon, so no advy has been
issued attm. Winds and seas blw sca lvls on Wed, then 5 ft seas
possible on the ocean Thu as low pres deepens over the Atlc.

&&

.HYDROLOGY...
No hydrologic impacts are expected through Friday. 0.25"-1.00" of
rainfall is forecast Sunday through Monday night, with locally
higher amounts possible.

&&

.TIDES/COASTAL FLOODING...
Tides will be running high astronomically with a new moon
phase. With an onshore flow becoming increasingly persistent
late this weekend there is the chance that some locations for
the Western Sound Shore in CT and the more western south shore
bays will approach their minor coastal flood benchmarks. This
will be possible for the Sunday night, Monday day time, and
Monday night tide cycles.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...Dense Fog Advisory until noon EDT today for ANZ331-332-335-338-
     340-345-350-353-355.
     Small Craft Advisory from 4 PM this afternoon to 6 PM EDT
     Monday for ANZ350-353-355.

&&

$$
SYNOPSIS...JMC/JP
NEAR TERM...JE/JP
SHORT TERM...JP
LONG TERM...JMC/JP
AVIATION...MET
MARINE...JMC/JE/MW
HYDROLOGY...JMC/JP
TIDES/COASTAL FLOODING...

NWS OKX Office Area Forecast Discussion