Area Forecast Discussion
Issued by NWS Upton, NY

Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
FXUS61 KOKX 231439

Area Forecast Discussion
National Weather Service New York NY
1039 AM EDT Mon May 23 2022

High pressure builds in today. Its center will slowly drift
east across southeastern Canada through Wednesday. A frontal
system approaches the area late in the week, and crosses the
region over the weekend.


Nudged maxTs down a degree or two based on current obs. Otherwise,
rest of forecast on track.

A zonal flow will be in place aloft with high pressure slowly
building in from the NW today. No rain, but the sky probably varies
between partly cloudy and mostly cloudy throughout the day. Models
generally agree that late afternoon would be the period with the
best chance of mostly cloudy conditions covering most of the
forecast area as mid level moisture increases. High temperatures
mostly in the mid 70s with a northerly wind.

An inverted trough stretches toward us from a low pressure center in
the Southeast tonight. This will be accompanied by shortwave energy
and lift. ECMWF and CMC have come into better agreement with NAM/GFS
with limited moisture convergence along the surface trough along
with very little to no precip across the area. Therefore still have
enough confidence to continue with a dry forecast, especially with
moisture lacking somewhat in the low levels. There could be at least
just a sprinkle in a few spots, but dry weather should prevail.


High pressure remains the dominant feature in the weather pattern
through the short term forecast period. Heights build aloft, and
this will help keep us dry in spite of mid level moisture lingering
during Tuesday. Mostly cloudy conditions will help hold high
temperatures to mostly 65-70. Although Wednesday is shaping up to be
less cloudy, southeast winds off the the chilly ocean waters hold
highs in the 65-70 range once again.

High pressure weakens Wednesday night, and the low pressure center
that had been in the Southeast begins to move up the Mid-Atlantic
Coast in a weakened state. Deep enough moisture ahead of it could
sneak into the forecast area late at night, so maintained some
continuity with the previous forecast and kept in slight chance to
chance PoPs.


Models in good agreement with deep Central US troughing developing
midweek, with upper ridging off the SE US Coast. Models then begin
to diverge on the evolution of the upper trough, with GEFS and GEPS
much deeper w/ closed southern low development and slower
progression of the upper trough/closed low through the region
Sat into Sun. The ECMWF ensemble meanwhile is more progressive
in shearing this trough NE through the region NE Fri Night. In
deference to this less progressive development over the last 12
hours, have coordinated with neighboring offices to include at
least a slight chance of shower through Saturday (higher than

At the surface, high pressure slides offshore on Thursday with
potential for a weak southern Mid-Atlantic wave to work up the coast
with some shower activity. A slow moving frontal system approaches
on Friday ahead of the above mentioned trough/closed low,
potentially being slow to move through until Saturday or Saturday
Night. Depending on this evolution, potential for scattered heavy
downpours and thunderstorms Friday afternoon, particularly NYC and
points N&W in axis of marginal instability, Gulf/Atlantic moisture
feed and approaching trough axis and pre-frontal trough. Rounds of
shower activity could continue Fri Night into Sat, with diurnal tsra
possible, if slower passage materializes.

Improving conds signaled for Sunday into Monday with eastward
progression of closed low, even in slower GEFS/GEPS.

Temps near or slightly below seasonable on Thu in developing return
flow, becoming slight above seasonable and humid Fri and Sat in deep
southerly flow ahead of slow moving frontal system, followed by
potential for above seasonable temps to end the Memorial Day weekend
with more in the way of sunshine.


High pressure builds to the NW of the terminals today.

VFR conditions through TAF period.

N-NW winds with occasional gusts to 20 kt this morning. Any
leftover gusts will subside by 18z. Then, north winds 8 to 12
kt are expected through the afternoon.

Low probability for late day sea breeze for JFK and ISP, better
chance at KGON.

Winds become light and variable tonight.

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

Low chance of early morning MVFR cigs. Any MVFR conditions
should be brief. Low chance of afternoon seabreezes.

.Tues...VFR. Isolated -shra possible. E/NE 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...MVFR possible in showers.

Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/


A weak pressure gradient will remain over the local area through
Thursday and promote sub-advisory conditions during this period.
Persistent southerly flow ahead of a slow moving cold front
will likely remain just below SCA, but the long and persistent
fetch will likely have marginal SCA ocean seas developing Friday
and continuing into the weekend.


A frontal system will likely bring periods of showers and
thunderstorms to the area late this week, and possibly into the
start of the weekend. Locally heavy downpours are possible as PWATS
approach 2", but predictability on rainfall amounts and any
hydrological impacts is low at this time.




HYDROLOGY...JC/NV is the U.S. government's official web portal to all federal, state and local government web resources and services.