876
FXUS61 KOKX 261819 CCA
AFDOKX
Area Forecast Discussion...CORRECTED
National Weather Service New York NY
219 PM EDT Sat Oct 26 2024
.SYNOPSIS...
-- Changed Discussion --
Behind a cold front, high pressure will build in through Monday.
The high builds offshore Monday night into Tuesday, while a warm
front lifts northeast across the Great Lakes. The latter of which
will pass through the area Tuesday night. The trailing cold front
over the Upper Mississippi Valley Wednesday will track east and
across the area late Thursday night into Friday morning.-- End Changed Discussion --
&&
.NEAR TERM /THROUGH TONIGHT/...
Still had to raise the high temperature forecast, which for
some locations has turned out to be above what the NBM 95th
percentile had forecast. So, again slightly increased the
temperatures with this update. Otherwise, forecast remains on
track.
Red Flag Warning remains in effect for the local tri-state area
until 7pm. See fire weather section for more details. Low RH
around 25 to 30 percent for most of the area and gusty winds to
near 25 to 30 mph.
For tonight, winds subside and RH goes up naturally as
temperatures lower. Expecting mostly clear sky conditions
tonight as high pressure continues to build in from the west.
MAV/MET blend for temperatures used with radiational cooling
expected.
The center of the high pressure area stays west of the
region and the pressure gradient remains tight enough between
this high and low pressure well into the Canadian Maritimes, to
keep a steady northerly flow much of the night but becoming
nearly calm for early Sunday morning.
Lows forecast range from the low 30s in interior and rural
locations and mid 40s within parts of NYC. Winds stay up enough
in the forecast to keep any frost formation patchy. However,
some forecast zones are expected to reach near freezing,
especially Orange and Putnam counties where growing season is
still active and forecast lows reach down to near 30 to 32.
Confidence currently not high on coverage of freezing to sub-
freezing temperatures and temporal coverage of this as well.
&&
.SHORT TERM /SUNDAY THROUGH MONDAY/...
A broad area of high pres builds in on Sun, resulting in light
winds and cooler temps. The NBM was followed for highs which
are progged to remain mainly in the 50s. A weak backdoor front
approaches from the N Sun ngt. As a result, the pres grad may
strengthen enough to develop a wly flow across the area and keep
temps from bottoming out. The guidance is generally split on
this, particularly near the coasts, so stuck close to the NBM
which is middle of the road. Some freezing temps will be
possible in the normally colder outlying areas.
The backdoor front comes thru on Mon with a change in wind
direction and reinforcement of the cooler airmass. No moisture
to work with so kept the fcst dry. The NBM was followed with
highs a little blw normal.
&&
.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
Surface high pressure builds offshore at the start of the period,
while a warm front lifts northeast across the Great Lakes. The
latter of which will pass through the area Tuesday night. This will
mark the start of an anomalously warm midweek period as a broad
upper ridge east of the Mississippi River Valley amplifies as it
works toward the eastern seaboard. A deep-layered WSW flow will
increase 85h temps to 12-14C by late Wednesday. NBM box and whisker
plots surprisingly show very little spread Wed and Thu. The NBM90 is
only a couple of degrees warmer than the deterministic, which is
fairly close to the median (50th percentile). Thus, confidence is
high for unusually warm temperatures of about 10 to 15 degree above
normal. Highs are forecast to get into the 70s for most locations,
with NE NJ up around 80 by Thursday. There is a bit more spread
though heading into Friday due to some timing differences amongst
the global models with a cold frontal passage. The only chance for
rain at this time looks to be from showers Thursday night into
Friday morning along and ahead of the cold front. This boundary like
many of late looks to lack decent forcing and moisture, but time
will tell.
&&
.AVIATION /18Z SATURDAY THROUGH THURSDAY/...
High pressure builds in through tonight.
VFR. NW winds 15-20 kt with gusts 25-30 kt. Winds diminish a little
this evening but remain gusty. Gusts then end overnight.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Occasional gusts of 30-33kt for mainly KJFK and KLGA, but up to 30kt
still possible for KEWR and KTEB.
Winds should prevail right (north) of 310 magnetic today.
End time of prevailing gusts may be off by a few hours - especially
with KJFK/KLGA/KEWR where gusts might be only occasional 4-5 hours
before indicated in TAFs.
OUTLOOK FOR 18Z SUNDAY THROUGH THURSDAY...
Sunday PM-Monday: VFR.
Tuesday: VFR, but chance of MVFR east of the city terminals.
Wednesday: VFR. SW wind gusts 15-20 kt possible.
Thursday: VFR. SW wind gusts 20-25 kt possible.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90
&&
.MARINE...
SCA remains in effect for all forecast waters through early this
evening for wind gusts up to near 25 kt. Gusts gradually subside
tonight, with NY Harbor dropping below SCA criteria after 8PM
and then all other non-ocean waters below SCA after 4AM Sunday.
The ocean SCA goes until 6AM Sunday where higher gusts will last
longest.
Winds and seas then look to remain blw sca lvls Sun thru Mon.
High pressure retreats offshore Monday night into Tuesday with a
gradually strengthening southerly flow. Ocean seas may reach 5
ft E of Fire Island Inlet Wed night as SW flow increases to
near 20 kt.
&&
.FIRE WEATHER...
Red Flag Warning remains in effect today for S CT, but has been
expanded to include the rest of the forecast zones in SE NY and
NE NJ, for elevated risk of fire growth/spread. Dry weather
will continue with RH lowering to near 20-30% across much of
the region. Gusty NW winds of 25-30 mph will develop and
continue through this afternoon. Relatively highest wind gusts
and lowest RH is expected between 2 and 5PM.
Winds will be considerably weaker for Sunday and Monday with
afternoon RH still low, 20-30% on Sunday and 30-40% on Mon.
&&
.HYDROLOGY...
There are no hydrologic concerns through the period.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...Red Flag Warning until 7 PM EDT this evening for CTZ005>012.
NY...Red Flag Warning until 7 PM EDT this evening for NYZ211>213.
NJ...Red Flag Warning until 7 PM EDT this evening for NJZ002-004-
006-103>108.
MARINE...Small Craft Advisory until 4 AM EDT Sunday for ANZ331-332-335-
340-345.
Small Craft Advisory until 8 PM EDT this evening for ANZ338.
Small Craft Advisory until 6 AM EDT Sunday for ANZ350-353-355.
&&
$$
SYNOPSIS...JMC/DW
NEAR TERM...JM
SHORT TERM...JMC
LONG TERM...DW
AVIATION...JC
MARINE...JMC/JM/DW
FIRE WEATHER...
HYDROLOGY...JMC/DW