000
FXUS61 KOKX 191533
AFDOKX

Area Forecast Discussion
National Weather Service New York NY
1133 AM EDT Thu Oct 19 2023

.SYNOPSIS...
High pressure along the Northeast and Mid Atlantic coast moves
into the western Atlantic Ocean as a frontal system approaches
to the west through tonight. A secondary low develops along the
Delmarva late Friday into Friday night and deepens through
Saturday night while tracking to the northeast. The low departs
to the northeast Sunday as high pressure builds in from the west
and settles over the region early next week. A frontal boundary
approaches late next week.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
The fog is eroding from the valleys of NE NJ and the lower
Hudson Valley as of 14Z. Vsbys will continue to improve in
these areas over the next hour or two. Given this, the SPS that
was in place was allowed to expire. Otherwise, updated the
weather, temperatures, dew points, and winds for the current
conditions and forecast remains on track.

Today will be dry and tranquil as upper ridging builds into the
northeast with the ridge axis moving to the east this afternoon
and off the northeast coast by this evening. Meanwhile, surface
high pressure moves into the western Atlantic. Temperatures
will be near seasonal normals with a light return flow, with dew
points gradually rising.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
An amplifying trough digging into the central US today  will
track east tonight into Friday. A northern stream frontal system
will be slowly deepening and tracks through the Great Lakes
region tonight into Friday afternoon. With a strong vort max
rotating into the upper trough, which becomes negative tonight,
will spin up a surface low along the mid Atlantic coast tonight.
There is still some guidance differences as to how far off the
coast the low will deepen and track to the northeast.

Precipitation with the developing coastal low will move up
along the coast tonight with chances of precipitation increasing
by late night across the southern portion of the forecast area,
and early Friday morning precipitation overspreads the area.
Late Friday night lift increases across eastern Long Island and
southeastern Connecticut as the mid level low of trough tracks
across this region. There will be developing instability along
with elevated CAPE, and a few thunderstorms will be possible
late night and toward Saturday morning, and have maintained the
chance for thunder. Model guidance suggests that there may be a
brief break, or the precipitation becoming light, Saturday
morning, and then increase again during the afternoon as the mid
and upper level low with the northern stream system tracks
across the region and merges over New England. Then Saturday
night with the upper trough and low lifting to the northeast the
precipitation winds down again.

&&

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
Low pressure continues to depart to the northeast on Sunday, with a
lingering upper level trough remaining over the area. Conditions
will be mainly dry on Sunday, however, a fairly tight pressure
gradient over there area between the departing low and high pressure
to the west will make for a rather gusty day. NW winds are expect to
gust up around 30-35 mph. Highs on Sunday will be in the middle and
upper 50s, but will feel a bit cooler with the gusty winds.

The gradient relaxes Sunday night, with gusts diminishing. A
shortwave in the upper trough will swing through the region late
Sunday night and Monday, which may result in some additional rain
showers, mainly east of NYC. Have bumped up POPs a bit to account
for this, but will keep POPS limited to just chance at this time.

Surface high pressure and upper level ridging then build into the
region Monday night and remain through Wednesday. As the high and
upper ridge move east late late Wednesday, a frontal boundary slowly
approaches from the west. There are some timing differences with
this boundary, so expected some possible changes late in the week
with respect to a chance of precipitation during the second half of
next week.

Temperatures each day next week gradually rise. Monday - middle
and upper 50s, Tuesday - upper 50s to lower 60s, Wednesday - lower
to middle 60s, and Thursday - middle to upper 60s. Lows overnight
will be in the 30s and 40s, with the coldest night expected to be
Monday night. There will be a chance of some frost Monday night,
especially across the usually colder spots in the forecast area.

&&

.AVIATION /16Z THURSDAY THROUGH MONDAY/...
-- Changed Discussion --
High pressure over the region will gradually shift offshore today. A frontal system will approach from the west. VFR expected through much of the TAF period. Clouds will increase late in the day and overnight, lowering to MVFR towards daybreak on Friday. In addition, expect rain showers to move into the region from the south, after 09z with more widespread shower activity after 12z. There is a chance that cigs lower to IFR after 12z, but held off on going that low right now. Southerly winds increasing to 8-12kt by afternoon. Winds will fall below 10kt everywhere tonight. ....NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty... Winds may remain closer to 240 true thru 17-18Z. OUTLOOK FOR 12Z FRIDAY THROUGH MONDAY... Friday through Saturday: MVFR/IFR with showers. Sunday: MVFR early, becoming VFR. W to NW wind gusts 25-30 kt. Monday: Mainly VFR. Chance of some showers early, mainly east of NYC. Gusty NW flow. Detailed information, including hourly TAF wind component forecasts, can be found at: https:/www.weather.gov/zny/n90
-- End Changed Discussion --
&& .MARINE... With a weak pressure gradient across the waters today and tonight winds and seas remain below advisory levels across the forecast waters. A southerly flow increases Friday into Friday night as a low pressure system approaches the waters to the west. And, during Saturday ocean seas will be building, reaching SCA levels in the morning. Then with a deepening low passing to the northeast of the waters Saturday night SCA gusts become likely across all the forecast waters. The pressure gradient over the area waters tightens on Sunday, bringing the best chance for gales to the ocean waters. While the chances for gales are lower on the non-ocean waters, can not rule out a few gust to gale force. Winds and seas with then gradually diminish Sunday night, with the non-ocean waters falling below SCA conditions, however the ocean will continue to see seas at or above 5ft through Sunday night. The seas on the ocean waters are forecast to fall below SCA levels Monday morning. By Monday afternoon or early evening, sub-SCA conditions are then expected on all the waters and should remain below SCA levels through Wednesday. && .HYDROLOGY... Rainfall of 0.75 to 1.25 inches is possible from late tonight through Saturday night, with most of the rainfall occurring Friday into Friday night. There are no flooding concerns at this time. And there are no hydrologic concerns Sunday through next week. && .OKX WATCHES/WARNINGS/ADVISORIES... CT...None. NY...None. NJ...None. MARINE...None. && $$ SYNOPSIS...BC/MET NEAR TERM...DR/MET SHORT TERM...MET LONG TERM...BC AVIATION...BC/JMC MARINE...BC/MET HYDROLOGY...BC/MET