781
FXUS61 KOKX 181748
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
148 PM EDT Sat May 18 2024
.SYNOPSIS...
-- Changed Discussion --
A couple of upper troughs will be in the vicinity through
tonight, otherwise surface high pressure will remain in control
through the middle of next week. A cold front approaches late in
the week.-- End Changed Discussion --
&&
.NEAR TERM /UNTIL 6 AM SUNDAY MORNING/...
-- Changed Discussion --
Minor adjustments made with this update, most notably, lowering
high temps for eastern LI and SE CT due to bkn-ovc sky and some
rainfall. Lift from a surface inverted trough and shortwave
shifting south and slightly west in this area have been
producing 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 this afternoon
into 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 near 60 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.-- End Changed Discussion --
&&
.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 SATURDAY/...
*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 /18Z SATURDAY THROUGH THURSDAY/...
-- Changed Discussion --
Weak high pressure remains along the northeast coast and into
the mid Atlantic through Sunday afternoon. A weakening trough
of low approaches from the west, and dissipates late tonight.
Conditions remained varied across the region, with MVFR east of
the New York City terminals, and VFR at the New York City
terminals and north and west. There is a chance of MVFR at the
western terminals with scattered light rain into early this
evening. During the early evening MVFR is expected to develop
throughout the area, with KGON becoming IFR. Brief IFR will be
possible at KISP toward Sunday morning. Areas of rain and
drizzle will be possible this evening and into early Sunday
morning.
Conditions may begin to improve toward 18Z Sunday. Moderate
confidence in the forecast, with timing uncertainties with
ceilings lowering.
Winds generally remain 10kt or less from the northeast
..NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Scattered MVFR ceilings are possible late afternoon with light
rain, then becoming MVFR. Moderate confidence with the timing of
lowering ceilings this evening.
OUTLOOK FOR 18Z SUNDAY THROUGH THURSDAY...
Sunday afternoon...MVFR early, then becoming VFR, except KGON
remaining MVFR. Becoming MVFR at night.
Monday...MVFR early morning, then VFR.
Tuesday-Wednesday...VFR.
Thursday...VFR, a chance of MVFR with showers and thunderstorms.
Detailed information, including hourly TAF wind component
forecasts, can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
-- Changed Discussion --
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.-- End Changed Discussion --
&&
.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
MARINE...NV/DW
HYDROLOGY...NV/DW