Area Forecast Discussion Issued by NWS Upton, NY
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000
FXUS61 KOKX 232241
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
641 PM EDT Mon May 23 2022
.SYNOPSIS...
High pressure slides offshore late Tuesday into Tuesday night
and then remains offshore through the end of the week. A slow
moving low pressure and frontal system will affect the area for
the weekend.
&&
.NEAR TERM /UNTIL 6 AM TUESDAY MORNING/...
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Forecast is on track with only minor changes needed.
Surface high pressure, centered near the Great Lakes, continues
to build into the region as it slides east. Expecting to keep a
decent amount of cloud cover tonight with increasing mid-level
moisture as a shortwave passes nearby. CAMs try and introduce
light rain for a period overnight as the disturbance tracks just
to our south, though low-levels appear too dry to support much
reaching the ground. Given this and limited moisture
convergence, maintained a dry forecast overnight, though an
isolated, spotty sprinkle is possible.
After a sultry weekend, temperatures have returned to near
seasonable levels for late May, and this continues into midweek.
Forecast lows tonight will generally bottom out in the 50s, to near
60 around the metro.-- End Changed Discussion --
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.SHORT TERM /6 AM TUESDAY MORNING THROUGH TUESDAY NIGHT/...
The weak flow regime continues on Tuesday as the region remains
stuck between lower pressures over the Southeast, and the high to
our north. Winds veer easterly/southeasterly early in the day as the
center of surface high pressure slips off the coast of New England
and the Canadian Maritimes. With the onshore flow and elevated mid-
level moisture, expecting more clouds than sun, which should inhibit
temperatures during the day. 850 temps fall from around 10C Monday,
to 5-6C on Tuesday. Coupled with the clouds, onshore flow, and
cooler air aloft, expecting maxTs to top out a few degrees cooler
than Monday, generally around 70 for most. Dry conditions continue
Tuesday night into Wed AM, with lows falling into the 50s. Didn`t
stray far from NBM deterministic for this forecast.
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.LONG TERM /WEDNESDAY THROUGH MONDAY/...
Tranquil conditions expected through Wednesday night and possibly
into Thursday as the center of high pressure off the New England
coast slowly drifts east over the north Atlantic. Aloft, zonal flow
transitions to a building ridge. Despite the building ridge an
onshore flow thanks to a developing maritime air mass during
this time frame will keep temperatures at or a few degrees below
normal.
Some uncertainty exists for Thursday morning with a weak low or
inverted trough off the mid-Atlantic Coast that may drift northward
Wednesday night into Thursday morning. Most deterministic models
have this feature in one form or another, but whether this makes it
into the area with some light precipitation, or perhaps low stratus
and drizzle (GFS forecast soundings suggest a very dry layer at
around 950-900 hPa) is still unknown. Capped POPs at slight chance
for Thursday due to uncertainty.
Thereafter, more significant uncertainty exists in the deterministic
models with the advance eastward of a cold front from the mid-West
on Thursday vs the potential for a low to cut-off over the Plains
states along the frontal boundary as it moves slowly toward the
region into the weekend. The frontal boundary will remain to the
north and west during this scenario, with prolonged onshore flow,
cooler than normal temperatures, and chances for precipitation from
Friday through the weekend. The ECMWF and GFS ensembles show a few
members with weak areas of low pressure at the surface that remain
to the west into Saturday night, lending credence to the cutoff. So,
will lean more towards the more pessimistic outcome for this time
period, but a total washout is not expected at this time. Given the
onshore flow, lowered temperatures a degree or two below NBM for
Friday and Saturday, which end up around normal for this time of
year.
The cutoff could still be plaguing the area Monday, situated to the
southeast over the mid-Atlantic. However, there is still a good deal
of uncertainty this far out and stuck with NBM for this time
frame.
&&
.AVIATION /00Z TUESDAY THROUGH SATURDAY/...
High pressure builds to the northwest of the terminals today,
then north of the terminals tonight.
VFR conditions through TAF period.
N-NW winds with occasional gusts to 20 kt will continue til
about 20-21z. Then, north winds 8 to 12 kt are expected through
the remainder of the afternoon, before becoming light and
variable tonight. There is a Low probability for late day sea
breeze at JFK.
Winds on Tuesday will be from the S-SE around 8-12kt.
NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Winds gusts may be occasional this afternoon. Low chance of
afternoon seabreezes at JFK today.
.OUTLOOK FOR 18Z TUESDAY THROUGH SATURDAY...
.Tues...VFR. E/SE winds.
.Wed-Wed Night...VFR.
.Thu...MVFR or lower possible at times. Chance of showers.
Slight chance of thunderstorms north and west of NYC.
.Fri and Sat...MVFR or lower in possible showers.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90
&&
.MARINE...
Winds and waves are expected to remain below SCA criteria
through Thursday night with a weak pressure gradient in place.
Waves build on a prolonged southerly flow over the ocean waters,
with 5 ft waves expected late Thursday night into Friday, which
could remain elevated into Saturday. Winds will remain below 25
kt through Thursday night. Gusts to around 25 kt are possible
on the ocean waters toward Friday afternoon given the approach
of a frontal system or low pressure from the west.
&&
.HYDROLOGY...
A frontal system will likely bring rain to the area late this week,
but there is too much uncertainty this far out in time in
determining any hydrological impacts, if any.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...None.
&&
$$
SYNOPSIS...JP/DR
NEAR TERM...JP/DR
SHORT TERM...DR
LONG TERM...JP
AVIATION...BC
MARINE...JP/DR
HYDROLOGY...JP/DR