716
FXUS61 KOKX 181452
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
1052 AM EDT Sat May 18 2024
.SYNOPSIS...
A weakening upper level trough will approach from the west today
and move across the area tonight, otherwise surface high pressure
will remain in control through the middle of next week. A cold
front approaches late in the week.
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
Updated the forecast to increase PoPs over eastern zones,
especially over SE CT. Lift from a surface inverted trough and
shortwave shifting south and slightly west in this area have
been producing some showers over the area. Thinking the activity
here decreases this afternoon as some CAMS imply. Meanwhile a
stronger shortwave to our SW may introduce showers across
southern/western portions of the forecast area mainly this
afternoon into early evening. High pressure will otherwise
continue to slowly ridge south across New England and into the
forecast area, and a large area of low pressure over the
western Atlantic continues to send moisture into the area.
Along with the chance of showers, plenty of cloud cover across
the region.
Highs are forecast to range from the lower 60s across far
eastern LI and SE CT, to around 70 from NYC and points north and
west. This is generally a few degrees below normal. However,
with the cloud cover, expect lows tonight in the 50s, slightly
above normal. Temperature guidance is generally in good
agreement with a slight upward trend.
&&
.SHORT TERM /6 AM SUNDAY MORNING THROUGH MONDAY/...
Surface high pressure along the new England coast remains in
control during this time. Patchy light rain/drizzle may linger
in the morning for far eastern areas, otherwise expect gradual
improvement with decreasing clouds from west to east in the
afternoon. This could be short-lived though for eastern LI and
SE CT, where low clouds may linger or redevelop during the
nighttime hours. Any clouds work east on Monday along with the
surface ridge axis. Aloft, a high amplitude ridge builds over
top of the area.
Temperatures will be on the uptick Sunday into Monday due to a
lot more sun. Sunday will be a touch warmer than Saturday, but
jumping to 75 to 80 north and west of NYC on Monday, with much
of the coast getting to around 70.
&&
.LONG TERM /MONDAY NIGHT THROUGH FRIDAY/...
*Key Points*
*Above normal temperatures through midweek.
*A cold front approaches late in the week, bringing the next
chance of showers and thunderstorms.
Upper ridging noses into the region from the southern US early to
mid week, becoming suppressed late in the week in response to a
developing closed upper low drifting east across the northern
plains/Great Lakes. Quite a bit of model spread on the evolution of
this low, which manifests in timing and progressiveness differences
in the resultant cold front pushing towards and into the region late
in the week.
Before then, good agreement in high pressure over the region this
weekend, slowly sinking se of the region and developing a return
deep SW flow into the region by midweek. The result will likely be
dry conditions with temps moderating to 10 to 15 degrees above
normal away from the coast Tue thru Thu. Based on setup, and 850mb
temps in the mid teens, have leaned away from cooler deterministic
NBM and towards the higher NBM 50th percentile (high in the mid 80s)
for NE NJ and areas to the NW. NBM 75th percentile has temps
approaching 90 in this area, which is plausible with deep mixing and
SW flow. Meanwhile, SW flow off mid 50 degree waters will likely
keep temps in 70s along the coast, but still seasonable.
Shower/tstm potential exists ahead/along pre-frontal trough and cold
front, but with aforementioned upper low and frontal timing
differences, have capped potential at low chance, possibly as early
as Wed eve, with better chance Thu aft/eve. CSU MLP marginal severe
storm threat for areas west of the Hudson River Wed eve, and the
entire area Thu aft/eve looks reasonable based on synoptic and
thermodynamic setup.
&&
.AVIATION /15Z SATURDAY THROUGH WEDNESDAY/...
-- Changed Discussion --
Weak high pressure will be in place today through Sunday, with a
weak warm front dissipating as it moves in from the west tonight.
Conditions vary across the region with MVFR east of the New York
City terminals, to the east of a ridge of high pressure, and VFR at
the New York City terminals and north and west, to the west of the
ridge. MVFR ceilings likely persist for the eastern terminals
through the day. Meanwhile NYC/NJ terminals will likely remain VFR,
with patchy MVFR ceilings possible this evening. Increasing
likelihood for MVFR cigs spreading west into NYC/NJ terminals
tonight, with widespread MVFR or lower cigs likely for Sun AM push.
Isolated shower/drizzle threat for eastern terminals into early this
afternoon, then showers for all terminals during the afternoon into
the evening.
NE/E winds 10 kt or less into tonight.
..NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Low prob for MVFR cigs with isolated showers possible for the eve
push. MVFR cigs likely for Sun AM push.
NE winds possibly becoming E/SE in the afternoon with hybrid sea
breeze development, except KLGA.
OUTLOOK FOR 12Z SUNDAY THROUGH WEDNESDAY...
Sunday...MVFR or lower in the AM, gradually improving to VFR.
Light E/NE winds.
Monday...MVFR AM, then VFR.
Tuesday-Wednesday...VFR.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
Based on recent buoy obs and guidance, dropped the SCA on the
ocean waters with the expectation of waves prevailing under 5 ft
for the rest of the day. Otherwise, a weak pressure gradient
over the waters will likely sustain sub SCA levels through the
middle of next week. The exception will be the potential for
marginal southerly SCA gusts in and around the entrance to NY
Harbor with coastal jet formation Wed aft/eve.
&&
.HYDROLOGY...
There are no hydrologic issues through the middle of next week.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...None.
&&
$$
SYNOPSIS...NV/DW
NEAR TERM...JC/DW
SHORT TERM...DW
LONG TERM...NV
AVIATION...MET/NV
MARINE...NV/DW
HYDROLOGY...NV/DW