Area Forecast Discussion Issued by NWS Upton, NY
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000
FXUS61 KOKX 080048
AFDOKX
Area Forecast Discussion
National Weather Service New York NY
848 PM EDT Sun Aug 7 2022
.SYNOPSIS...
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High pressure will remain anchored offshore over the western
Atlantic, with a surface trough remaining across the area through
Tuesday. A cold front approaches late Tuesday and will slowly
move across the area Tuesday night into Wednesday, stalling just
south of the region. A series of weak frontal waves will ride
along the front during the midweek period before a secondary
cold front passes through the area Thursday night. High pressure
will then slowly build in behind the front for next weekend.-- End Changed Discussion --
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
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Evening showers and thunderstorms will continue to dissipate
over the next couple of hour with loss of surface based
instability. Perhaps an isolated shower overnight with weak vort
energy across E PA moving through, otherwise, another warm and
muggy night with patchy fog across interior and possibly
southeastern coastal areas.
Lows ranging from the lower 70s far inland, to mid to upper 70s
coast, and around 80 urban NYC/NJ.-- End Changed Discussion --
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.SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/...
A largely unchanged synoptic pattern continues into Monday with
broad ridging aloft, high pressure situated offshore, and a slow-
moving cold front well off to the north and west. The front,
extending from the Great Lakes to New England, will move slowly
during the day Monday, so expect similar conditions to Sunday.
Once again the main story will be the heat as 850 mb temperatures
climb to around 20C. Daytime highs should be a degree or two warmer
than Sunday, with highs in the low-to-mid 90s for most. Heat Indices
will once again be in the 95-99 range, with some areas, mainly in
the urban corridor reaching the 100+ mark. As a result, the Heat
Advisories remain up through Monday evening
A quick note: A few isolated spots, specifically in the urban
corridor of NE NJ, may briefly touch 105F, however coverage does not
look expansive enough to warrant a warning at this time.
With the surface trough expected to remain nearby, afternoon showers
and thunderstorms appear possible once again. Its hard to say
exactly where any boundaries will set up at this point, so will
continue to carry just some chance/slight chance POPs, mainly NYC
and points north and west. With the tropical airmass in place, any
storms will continue to pose a risk of localized flooding.
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.LONG TERM /TUESDAY THROUGH SUNDAY/...
High heat and humidity will persist one more day to start the
extended period with anomalously warm heights aloft and the western
Atlantic Ridge (aka Bermuda High) remaining in place. The one caveat
is a cold front approaching from the NW on Tuesday limiting the
amount of heating due to clouds and convection. This scenario is
more plausible across the Lower Hudson Valley. Highs were a blend of
the previous forecast and the slightly warmer NBM. This puts highs
in the lower to mid 90s (possibly a bit warmer across metro NJ) for
most location, with the immediate coast in the 80s to around 90.
This coupled with dew points in the lower 70s, will produce another
day of 95 to 100 heat indices. Thus, the heat advisory has been
extended through Tuesday.
An initial mid level shortwave sends a weak cold front across the
area late Tuesday afternoon into the first half of the night. Weak
shear, modest instability, poor mid-level lapse rates, and high PW
values, all point to heavy rain concerns with potential training
from west to east along the boundary. However, the overall forcing
is weak and with the lack of shear for cold pool maintenance, the
convection should be relatively weak, short-lived, and diurnally
driven. Still though, localized flash flooding seems plausible at
this time.
The kicker will come in the form of an amplifying upper trough
dropping southeast from Central Canada and into the Great Lakes from
Wednesday into Friday. Post-frontal showers/isolated thunderstorm
are likely to linger into Thursday, but then work east on Friday as
a secondary cold front associated with the upper trough passes
through. High pressure will then follow for next weekend. There is a
low probability of showers Saturday afternoon as the upper trough
could close off over the Northeast. For the time, have left it out
of the forecast.
A much drier and seasonable airmass follows for Friday and the
weekend.
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.AVIATION /00Z MONDAY THROUGH FRIDAY/...
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Bermuda high pressure remains in control through Tuesday with weak
surface trough development near NYC/NJ metro terminals and just
to the west for Monday afternoon.
Mainly VFR. Patchy stratus MVFR development possible once again
late tonight into early Monday morning. Isolated to scattered
thunderstorm development expected for the NYC/NJ metro and
Lower Hudson Valley Monday afternoon into the early evening.
This is being covered with PROB30 for the aforementioned
terminals.
S-SW winds below 10 kt late at night and into early Monday
morning before increasing to 10 to 15 ktg20-25kt again Monday
afternoon/early evening. KJFK could see sustained southerly
winds around 20kt Mon afternoon.
...NY Metro (KEWR/KLGA/KJFK/KTEB) TAF Uncertainty...
Isolated tstm development between 18 and 24z Monday. SW gusts 20
to 25 kt in the afternoon for KEWR/KTEB/KLGA, with sustained S
near 20 kt likely for JFK between 19z and 24z.
.OUTLOOK FOR 00Z TUESDAY THROUGH FRIDAY...
.Monday Night...Mainly VFR. SW winds 8-12kt.
.Tuesday...Chance of showers and thunderstorms for NYC metro
terminals and points N&W in the aft/early eve. SW winds G20 kt
possible by afternoon.
.Wednesday..Showers and thunderstorms, especially in the
afternoon and early evening with MVFR at times. SW-SW winds
G20kt possible.
.Thursday...Chance of showers and thunderstorm with MVFR
possible at times.
.Friday...VFR, with light NNW winds.
Detailed information, including hourly TAF wind component forecasts,
can be found at: https:/www.weather.gov/zny/n90-- End Changed Discussion --
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.MARINE...
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Marginal SCA winds gusts for the ocean and southern and eastern
bay and sound waters lower back below SCA criteria late tonight
into first part of Monday, however, by about midday Monday,
conditions return back to SCA criteria and remain up through
Monday night. Ocean seas will expected to build above 5 ft
Monday aft/eve as a result. SCA may need to be expanded to the
southern and eastern bays for Monday afternoon/early eve. Right
now, conditions look marginal and wind gusts to 25kt may be
occasional.
Marginal SCA conditions may linger across the ocean waters east of
Fire Island Inlet on Tuesday ahead of an approaching cold front.
Conditions should improve Wednesday into Thursday due to a weaker
gradient over the waters-- End Changed Discussion --
&&
.HYDROLOGY...
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Any training convection on Monday will be capable of producing
localized flash flooding with the moist and unstable airmass in
place (PWATS around 2") and efficient warm rain processes
(freezing level up near 15kft).
Showers and thunderstorms are possible again along and ahead of a
slow moving cold front late Tuesday afternoon into Wednesday and
potentially Thursday. Potential training of cells will have to be
monitored for flash flooding concerns, but it`s too early at this
time to be specific with details.-- End Changed Discussion --
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.TIDES/COASTAL FLOODING...
There is a high rip current through Monday for all but the NYC ocean
beaches, where the threat is moderate.
The moderate to high risk is a function of a S-SW flow each
afternoon increasing to around 15 kt with 4-5 ft southerly wind
waves.
&&
.OKX WATCHES/WARNINGS/ADVISORIES...
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CT...Heat Advisory until 8 PM EDT Tuesday for CTZ005>012.
NY...Heat Advisory until 8 PM EDT Tuesday for NYZ067>075-078>081-
176>179.
High Rip Current Risk through Tuesday evening for NYZ080-081-
179.
NJ...Heat Advisory until 8 PM EDT Tuesday for NJZ002-004-006-
103>108.
MARINE...Small Craft Advisory until 6 AM EDT Tuesday for ANZ350-353-355.-- End Changed Discussion --
&&
$$
SYNOPSIS...BC/DW
NEAR TERM...BC/NV
SHORT TERM...BC
LONG TERM...DW
AVIATION...NV
MARINE...BC/DW
HYDROLOGY...BC/DW
TIDES/COASTAL FLOODING...