000
FXUS61 KOKX 111828
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
228 PM EDT Mon Sep 11 2023
.SYNOPSIS...
Weak low pressure and a cold front slowly shift through the area
today into this evening, moving farther offshore overnight. The next
frontal system approaches on Tuesday and passes through on
Wednesday. High pressure will then be in control Thursday and
Friday.
&&
.NEAR TERM /THROUGH TONIGHT/...
Forecast remains on track. Widely scattered showers continue to
break out across the CWA with most of the storms having little
movement to them. With additional showers and thunderstorms
expected later today, a flood watch remains in effect til
midnight.
Otherwise, weak low pressure and cold front will be slowly
shifting through the region today. Lift from both features, in
addition to a mid level shortwave shifting through near the NW
zones late morning into the afternoon, will help trigger showers
with a chance of thunderstorms.
Flooding remains the primary concern for storms this afternoon.
Cell training along with slow forward motion presents a threat
of at least minor flooding. PWATs will remain 1.5-2.0 inches
this afternoon. In general, CAMs have not performed too well
over the past 24 hours with rain distribution, but some hi- res
guidance such as HREF did a decent job predicting at least where
rain would develop and shift (and timing) with Friday`s and
Saturday`s rainfall - not so much for Sunday. FFG values have
lowered in some areas due to Sunday`s rainfall, particularly in
parts of CT where rain over the past 24 hours has been
relatively higher. WPC has much of the area in a slight risk
for flash flooding.
Still muggy today with dewpoints averaging around 70 before falling
tonight. High temperatures in the upper 70s to lower 80s. Rain
threat shifts east tonight, lowering while doing so as the weak cold
front moves through. Lows tonight mostly 65-70.
&&
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
The weak low and cold front will slowly shift farther out to sea on
Tuesday, but any surface ridging over the forecast area will be
short-lived as the next system approaches from the west. Can`t
completely rule out a shower or thunderstorm during the day as a
shortwave passes through. Most, if not all of the day will be dry
however. Still muggy as dewpoints will still be in the range of
65- 70. High temps generally around 80 - slightly higher than
normal.
The 500mb longwave pattern then becomes more amplified Tuesday night
into Wednesday as a trough axis, and possibly a closed 500mb low,
shifts in the vicinity if the eastern Great Lakes Region. This
will help send a cold front our way Tuesday night, with the
front progged to pass through during Wednesday. Some
disagreement regarding the timing of the frontal passage, which
will have some implications on the severe weather potential.
Should a later passage occur, a better chance of strong gusts as
0-6km bulk shear could be 25-35 kt. PWATs increase ahead of the
cold front, so will need to monitor trends for flooding
potential. In any case, it appears that rain will be likely on
Wednesday with some thunderstorm potential.
&&
.LONG TERM /THURSDAY THROUGH MONDAY/...
The airmass dries out significantly on Thu and thru the
remainder of the extended. In the absence of any impacts from
Lee, fair wx can be expected.
The NBM with local adjustments was used for temps thru the period.
Monitor https:/www.weather.gov/okx/tropical or
https:/www.nhc.noaa.gov for the latest NHC forecasts on Hurricane
Lee and others.
&&
.AVIATION /18Z MONDAY THROUGH SATURDAY/...
-- Changed Discussion --
A frontal boundary across the region will slowly move east of
the region late tonight into Tuesday.
Showers with a few thunderstorms across the region going into
the middle of this afternoon. Thunderstorms grow in coverage
late this afternoon into early this evening. Shower and
thunderstorm coverage decreases thereafter with mainly dry
conditions anticipated for the remainder of the TAF period.
Conditions much of the TAF period are expected to be VFR but
brief MVFR to IFR visibilities will be possible with showers and
thunderstorms. Also, there could be some localized MVFR stratus
this afternoon into this evening. Otherwise, some MVFR stratus
is forecast late tonight into Tuesday morning with potential for
IFR stratus.
Winds will be less than 10 kts through the TAF period. Wind
direction will be more variable especially tonight into Tuesday
morning. There will be some southerly flow this afternoon into early
evening as well as Tuesday afternoon.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Wind direction forecast low confidence.
Timing of thunderstorms could be 1-2 hours off.
Timing of categorical changes could be 1-3 hours off.
OUTLOOK FOR 18Z TUESDAY THROUGH FRIDAY...
Tuesday afternoon - Tuesday night: Mainly VFR. Slight chance of
a shower or thunderstorm.
Wednesday: MVFR to IFR at times. Periodic showers. A chance of
thunderstorms. Showers and thunderstorms taper off at night.
Thursday - Friday: VFR. Northerly wind gusts around 15 to 20 kt
Thursday night through Friday night.
Saturday: Mainly VFR. NW wind gusts around 20 to 25 kt.
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 in place, winds and seas will remain
below SCA thresholds today through Tuesday. While winds remain
below advisory levels on Wednesday, swell from tropical system Lee
may push seas above 5 ft, with elevated seas then lasting through
the end of the week. Seas around 15 ft possible Fri-Sat.
Monitor https:/www.weather.gov/okx/tropical or
https:/www.nhc.noaa.gov for the latest NHC forecasts on Hurricane
Lee and others.
&&
.HYDROLOGY...
Primarily minor small stream and poor drainage flooding is
possible today, but flash flooding is possible as explained in
the near term section of this forecast discussion. Flooding is
not anticipated for Tuesday, then on Wednesday there is a risk
for primarily minor flooding with a low chance of flash
flooding. Locally up to 2 inches of rainfall is possible both
today and again on Wednesday, but for both events amount of a
half inch to an inch and a half are more likely.
No hydrologic impacts are expected in the long term.
&&
.TIDES/COASTAL FLOODING...
There is a moderate rip current risk at the Atlantic beaches
today and Tuesday. This risk increases on Wednesday, with both high
surf and dangerous rips possible on the oceanfront as early as
Thursday. This would then continue into Friday and and Saturday.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...Flood Watch until midnight EDT tonight for CTZ005>012.
NY...Flood Watch until midnight EDT tonight for NYZ067>075-078>081-
176>179.
NJ...Flood Watch until midnight EDT tonight for NJZ002-004-006-
103>108.
MARINE...None.
&&
$$
SYNOPSIS...JC
NEAR TERM...BC/JC
SHORT TERM...JC
LONG TERM...JMC
AVIATION...JM
MARINE...JMC/JC
HYDROLOGY...JC
TIDES/COASTAL FLOODING...