000
FXUS61 KOKX 311719
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
119 PM EDT Wed May 31 2023
.SYNOPSIS...
High pressure will remain in control through Friday. A back door
cold front will pass through Friday night into early Saturday,
followed by high pressure building from the north. Another cold
front may pass on Tuesday or Wednesday.
&&
.NEAR TERM /THROUGH TONIGHT/...
The forecast remains on track. Slight adjustments were made to
temperatures and dewpoints to better match observed trends.
Deep-layered ridge remains over the region during the near term.
Stratus and patchy fog burn off this morning, leaving us
without any clouds, but still some haze around due to the
wildfire in southern Nova Scotia. Smoke closer to the surface
will be patchy with minor visibility restriction if any and this
will be mainly across western sections as noted from recent runs
of the HRRR parameter of near surface smoke. High temperatures
will be near normal.
A light southerly flow develops tonight, and models are pointing to
greater coverage of low stratus and patchy fog than early this
morning. Moisture will be very shallow under a subsidence inversion
along with a lack of lift, so no drizzle expected with this. Lows
mostly in the 50s.
&&
.SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/...
High pressure ridge remains in place on Thursday with temperatures
aloft warming up. Sunny with above normal temperatures. Subsidence
and a southerly flow will limit the mixing depth for coastal areas,
while inland spots could see mixing up to around 900mb. Based on
temps at the top of the mixed layer and wind direction,
deterministic NBM looked reasonable. Highs ranging from the mid 80s
inland to the mid 70s for the southern-facing coasts.
Ridging aloft begins to break down on Friday as a 500mb trough drops
down south into Northern New England and begins its attempt late at
night to close off from the longwave pattern. This will send a
backdoor cold front our way which is expected to pass through late
at night. A pre-frontal trough will be around during the day, and
with some PVA and instability, there could be an afternoon shower or
thunderstorm north of the city. Chances are low overall as
convective and/or mechanical lift might not be enough to overcome an
eroding mid-level cap. High temperatures will be even warmer this
time around as 850mb temps rise to 16-17C. Highs around 90 inland
with 80s in most coastal spots.
Chances of showers and with a possible thunderstorm then increase at
night for the entire area with better overall lift ahead of the
passing cold front and deeper moisture. Winds through the mid levels
are weak as they back with height, so no concerns regarding severe
weather in any thunderstorms that develop.
&&
.LONG TERM /SATURDAY THROUGH TUESDAY/...
Stuck fairly close to the NBM through the long term period.
The weekend will be much cooler with the passage of a back door cold
front and the easterly flow that follows. A cyclonic flow aloft will
bring a chance of showers to the area during the day Saturday. While
Sunday appears to be a drier day, still can not rule out a few
showers and will continue to mention at least slight chance POPs
for now. Temperatures both Saturday and Sunday will be in the 60s to
lower 70s.
Temperatures warm back into the 70s for the beginning and middle
part of next week. Depending on the exact track of an offshore
low, there could be some showers around the area Monday into
Tuesday. A cold frontal passage is then expected on Tuesday or
Wednesday, however there continues to be timing issues with the
timing of this front. Will carry either chance or slight chance POP
to account both the offshore low and the cold frontal passage.
&&
.AVIATION /17Z WEDNESDAY THROUGH SUNDAY/...
-- Changed Discussion --
High pressure remains in the vicinity of terminals for the TAF
period.
VFR this afternoon into the evening. Low stratus/fog will then
return after 03Z east to west, bringing IFR or lower conditions
especially from the NYC terminals on east.
Winds will be from the E-SE today around 10kt or less.
Smoke from Canadian wildfires could limit visibilities to
around 5sm at times into this evening. Thus, slant range
visibilities may be reduced to 4sm or less.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Timing of onset of MVFR to sub MVFR cigs overnight may be off
by an hour or two. It is also uncertain as to how far west the
low stratus will make it, possibly only impacting KEWR/KTEB for
only an hour or two overnight/early Thursday am.
There remains some uncertainty with how much surface
restrictions to sky/vsby there will be with the haze and smoke
through this afternoon.
OUTLOOK FOR 18Z THURSDAY THROUGH SUNDAY...
Thursday: Low fog and Stratus will result in MVFR or lower
conditions early Thursday morning, then VFR.
Friday: Mainly VFR. Low chance of showers/thunderstorms and MVFR,
mainly at night.
Saturday: MVFR possible with a chance of showers throughout the day.
NE-E winds near 10-15kt with gusts near 20-25kt, highest at the
coastal terminals.
Sunday: Becoming VFR.
Monday: MVFR possible in afternoon showers.
Detailed information, including hourly TAF wind component
forecasts, can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
&&
.MARINE...
Conditions across all area waters will be below advisory criteria
through Friday with a relatively weak pressure gradient in place.
Winds will be at 10 kt or lower through the period with swells below
5 ft.
SCA conditions seem somewhat likely on Saturday with the next cold
front that moves across the region. The SCA conditions are expected
into at least Sunday morning, before starting to fall below SCA
criteria either late Sunday or Sunday night. Another chance of SCA
conditions comes late Monday or Monday night with an offshore low
passing nearby.
&&
.HYDROLOGY...
No hydrologic impacts expected through early next week.
&&
.TIDES/COASTAL FLOODING...
A moderate rip current risk is expected for both today and
Thursday.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...None.
NJ...None.
MARINE...None.
&&
$$
SYNOPSIS...BC/JC
NEAR TERM...JC
SHORT TERM...JC
LONG TERM...BC
AVIATION...DBR
MARINE...BC/JC
HYDROLOGY...BC/JC
TIDES/COASTAL FLOODING...