Alert archive / New York / Flash Flood Watches in 2020

Flash Flood Watch 2, NWS New York, NY

August 2, 20209 counties in New York; 5 counties in New Jersey; Greater Bridgeport Planning Region, Naugatuck Valley Planning Region, Connecticut

NWS New York, NY issued this flash flood watch at Aug 2, 2020, 3:32 PM EDT for 9 counties in New York; 5 counties in New Jersey; Greater Bridgeport Planning Region, Naugatuck Valley Planning Region, Connecticut. It took effect at Aug 4, 2020, 6:00 AM EDT. It was in force for 9 hr.

The area

The counties it named.

The facts

Issued
Aug 2, 2020, 3:32 PM EDT (19:32 UTC)
In effect from
Aug 4, 2020, 6:00 AM EDT
Expired
Aug 4, 2020, 3:15 PM EDT
In force
9 hr
Issued by
NWS New York, NY
Flood severity
None

Counties Greater Bridgeport Planning Region, CT, Naugatuck Valley Planning Region, CT, Bergen County, NJ, Essex County, NJ, Hudson County, NJ, Passaic County, NJ, Union County, NJ, Bronx County, NY, Kings County, NY, New York County, NY, Orange County, NY, Putnam County, NY, Queens County, NY, Richmond County, NY, Rockland County, NY, Westchester County, NY

The radar

The Brookhaven radar (KOKX), 91 km from the middle of the area, began a volume at 19:32 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Brookhaven, NY (KOKX), launched 12:00Z, 7.5 hours before the alert went out and 91 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Brookhaven, NY at 12:00Z on 2020-08-02Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Brookhaven, NY at 12:00Z on 2020-08-02The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 66 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
940 m above ground
0-6 km bulk shear
33 kt
0-1 km storm-relative helicity
66 m²/s²
0-3 km storm-relative helicity
129 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.4

Open this sounding in Storm Lab

The text

As transmitted.

994 
WGUS61 KOKX 021932
FFAOKX

URGENT - IMMEDIATE BROADCAST REQUESTED
Flood Watch
National Weather Service New York NY
332 PM EDT Sun Aug 2 2020

...FLASH FLOODING POSSIBLE TUESDAY INTO TUESDAY NIGHT...

NJZ002-004-006-103>108-NYZ067>075-176-178-030845-
/O.NEW.KOKX.FF.A.0002.200804T1000Z-200805T1000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Western Passaic-Eastern Passaic-Hudson-Western Bergen-
Eastern Bergen-Western Essex-Eastern Essex-Western Union-
Eastern Union-Orange-Putnam-Rockland-Northern Westchester-
Southern Westchester-New York (Manhattan)-Bronx-
Richmond (Staten Island)-Kings (Brooklyn)-Northern Queens-
Southern Queens-
332 PM EDT Sun Aug 2 2020

...FLASH FLOOD WATCH IN EFFECT FROM TUESDAY MORNING THROUGH LATE
TUESDAY NIGHT...

The National Weather Service in Upton has issued a

* Flash Flood Watch for portions of northeast New Jersey and 
  southeast New York, including the following areas, in 
  northeast New Jersey, Eastern Bergen, Eastern Essex, Eastern 
  Passaic, Eastern Union, Hudson, Western Bergen, Western Essex, 
  Western Passaic, and Western Union. In southeast New York, 
  Bronx, Kings (Brooklyn), New York (Manhattan), Northern 
  Queens, Northern Westchester, Orange, Putnam, Richmond (Staten 
  Island), Rockland, Southern Queens, and Southern Westchester. 

* From Tuesday morning through late Tuesday night

* Rain showers with embedded thunderstorms out ahead and with
  Tropical Storm Isaias will move into the region Tuesday into
  Tuesday night. A total of 2 to 4 inches of rain will be possible
  with locally higher amounts between 4 and 6 inches. Torrential 
  downpours with multiple rounds of heavy showers will allow for 
  excessive runoff and therefore would cause flash flooding in low
  lying, urban and poor drainage areas. Some smaller streams and 
  rivers may exceed their banks.


PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may develop that lead
to flash flooding. Flash flooding is a very dangerous situation.
You should monitor later forecasts and be prepared to take action
should flash flood warnings be issued.

&&

$$
5 follow-up statements
435 
WGUS61 KOKX 030231
FFAOKX

Flood Watch
National Weather Service New York NY
1031 PM EDT Sun Aug 2 2020

...FLASH FLOODING POSSIBLE TUESDAY INTO TUESDAY NIGHT...

NJZ002-004-006-103>108-NYZ067>075-176-178-031545-
/O.CON.KOKX.FF.A.0002.200804T1000Z-200805T1000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Western Passaic-Eastern Passaic-Hudson-Western Bergen-
Eastern Bergen-Western Essex-Eastern Essex-Western Union-
Eastern Union-Orange-Putnam-Rockland-Northern Westchester-
Southern Westchester-New York (Manhattan)-Bronx-
Richmond (Staten Island)-Kings (Brooklyn)-Northern Queens-
Southern Queens-
1031 PM EDT Sun Aug 2 2020

...FLASH FLOOD WATCH REMAINS IN EFFECT FROM TUESDAY MORNING
THROUGH LATE TUESDAY NIGHT...

The Flash Flood Watch continues for

* Portions of northeast New Jersey and southeast New York, 
  including the following areas, in northeast New Jersey, 
  Eastern Bergen, Eastern Essex, Eastern Passaic, Eastern Union, 
  Hudson, Western Bergen, Western Essex, Western Passaic, and 
  Western Union. In southeast New York, Bronx, Kings (Brooklyn), 
  New York (Manhattan), Northern Queens, Northern Westchester, 
  Orange, Putnam, Richmond (Staten Island), Rockland, Southern 
  Queens, and Southern Westchester. 

* From Tuesday morning through late Tuesday night

* Rain showers with embedded thunderstorms out ahead and with 
  Tropical Storm Isaias will move into the region Tuesday into 
  Tuesday night. A total of 2 to 4 inches of rain will be 
  possible with locally higher amounts between 4 and 6 inches. 
  Torrential downpours with multiple rounds of heavy showers 
  will allow for excessive runoff and therefore would cause 
  flash flooding in low lying, urban and poor drainage areas. 
  Some smaller streams and rivers may exceed their banks. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may develop that lead
to flash flooding. Flash flooding is a very dangerous situation.
You should monitor later forecasts and be prepared to take action
should flash flood warnings be issued.

&&

$$
649 
WGUS61 KOKX 030747
FFAOKX

Flood Watch
National Weather Service New York NY
347 AM EDT Mon Aug 3 2020

...FLASH FLOODING POSSIBLE TUESDAY INTO TUESDAY NIGHT...

NJZ002-004-006-103>108-NYZ067>075-176-178-032200-
/O.CON.KOKX.FF.A.0002.200804T1000Z-200805T1000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Western Passaic-Eastern Passaic-Hudson-Western Bergen-
Eastern Bergen-Western Essex-Eastern Essex-Western Union-
Eastern Union-Orange-Putnam-Rockland-Northern Westchester-
Southern Westchester-New York (Manhattan)-Bronx-
Richmond (Staten Island)-Kings (Brooklyn)-Northern Queens-
Southern Queens-
347 AM EDT Mon Aug 3 2020

...FLASH FLOOD WATCH REMAINS IN EFFECT FROM TUESDAY MORNING
THROUGH LATE TUESDAY NIGHT...

The Flash Flood Watch continues for

* Portions of northeast New Jersey and southeast New York, 
  including the following areas, in northeast New Jersey, 
  Eastern Bergen, Eastern Essex, Eastern Passaic, Eastern Union, 
  Hudson, Western Bergen, Western Essex, Western Passaic, and 
  Western Union. In southeast New York, Bronx, Kings (Brooklyn), 
  New York (Manhattan), Northern Queens, Northern Westchester, 
  Orange, Putnam, Richmond (Staten Island), Rockland, Southern 
  Queens, and Southern Westchester. 

* From Tuesday morning through late Tuesday night

* Rain showers with embedded thunderstorms out ahead and with 
  Tropical Storm Isaias will move into the region Tuesday into 
  Tuesday night. A total of 2 to 4 inches of rain will be 
  possible with locally higher amounts between 4 and 6 inches. 
  Torrential downpours with multiple rounds of heavy showers 
  will allow for excessive runoff and therefore would cause 
  flash flooding in low lying, urban and poor drainage areas. 
  Some smaller streams and rivers may exceed their banks. 


PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may develop that lead
to flash flooding. Flash flooding is a very dangerous situation.
You should monitor later forecasts and be prepared to take action
should flash flood warnings be issued.

&&

$$
613 
WGUS61 KOKX 031915
FFAOKX

URGENT - IMMEDIATE BROADCAST REQUESTED
Flood Watch
National Weather Service New York NY
315 PM EDT Mon Aug 3 2020

...FLASH FLOODING POSSIBLE TUESDAY INTO TUESDAY NIGHT...

CTZ005-006-041000-
/O.EXA.KOKX.FF.A.0002.200804T1000Z-200805T1000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Northern Fairfield-Northern New Haven-
315 PM EDT Mon Aug 3 2020

...FLASH FLOOD WATCH IN EFFECT FROM TUESDAY MORNING THROUGH LATE
TUESDAY NIGHT...

The National Weather Service in Upton has expanded the

* Flash Flood Watch to include a portion of southern 
  Connecticut, including the following areas, Northern Fairfield 
  and Northern New Haven. 

* From Tuesday morning through late Tuesday night

* Tropical Storm Isaias is expected to move across the area on
  Tuesday. A total of 2 to 4 inches of rain will be possible with
  locally higher amounts between 4 and 6 inches. Torrential 
  downpours with multiple rounds of heavy showers will allow for 
  excessive runoff and therefore would cause flash flooding in low
  lying, urban and poor drainage areas. Some rivers and streams 
  across the path of the heavier rainfall axis could experience 
  minor to moderate rises resulting in possible road closures and 
  inundation of structures near the streams. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may develop that lead
to flash flooding. Flash flooding is a very dangerous situation.
You should monitor later forecasts and be prepared to take action
should flash flood warnings be issued.

&&

$$

NJZ002-004-006-103>108-NYZ067>075-176-178-041000-
/O.CON.KOKX.FF.A.0002.200804T1000Z-200805T1000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Western Passaic-Eastern Passaic-Hudson-Western Bergen-
Eastern Bergen-Western Essex-Eastern Essex-Western Union-
Eastern Union-Orange-Putnam-Rockland-Northern Westchester-
Southern Westchester-New York (Manhattan)-Bronx-
Richmond (Staten Island)-Kings (Brooklyn)-Northern Queens-
Southern Queens-
315 PM EDT Mon Aug 3 2020

...FLASH FLOOD WATCH REMAINS IN EFFECT FROM TUESDAY MORNING
THROUGH LATE TUESDAY NIGHT...

The Flash Flood Watch continues for

* Portions of northeast New Jersey and southeast New York, 
  including the following areas, in northeast New Jersey, 
  Eastern Bergen, Eastern Essex, Eastern Passaic, Eastern Union, 
  Hudson, Western Bergen, Western Essex, Western Passaic, and 
  Western Union. In southeast New York, Bronx, Kings (Brooklyn), 
  New York (Manhattan), Northern Queens, Northern Westchester, 
  Orange, Putnam, Richmond (Staten Island), Rockland, Southern 
  Queens, and Southern Westchester. 

* From Tuesday morning through late Tuesday night

* Tropical Storm Isaias is expected to move across the area on
  Tuesday. A total of 2 to 4 inches of rain will be possible with
  locally higher amounts between 4 and 6 inches. Torrential 
  downpours with multiple rounds of heavy showers will allow for 
  excessive runoff and therefore would cause flash flooding in low
  lying, urban and poor drainage areas. Some rivers and streams 
  across the path of the heavier rainfall axis could experience 
  minor to moderate rises resulting in possible road closures and 
  inundation of structures near the streams. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may develop that lead
to flash flooding. Flash flooding is a very dangerous situation.
You should monitor later forecasts and be prepared to take action
should flash flood warnings be issued.

&&

$$
905 
WGUS61 KOKX 040833
FFAOKX

Flood Watch
National Weather Service New York NY
433 AM EDT Tue Aug 4 2020

...FLASH FLOODING POSSIBLE WITH TROPICAL STORM ISAIAS...

CTZ005-006-NJZ002-004-006-103>108-NYZ067>075-176-178-042145-
/O.CON.KOKX.FF.A.0002.200804T1000Z-200805T1000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Northern Fairfield-Northern New Haven-Western Passaic-
Eastern Passaic-Hudson-Western Bergen-Eastern Bergen-
Western Essex-Eastern Essex-Western Union-Eastern Union-Orange-
Putnam-Rockland-Northern Westchester-Southern Westchester-
New York (Manhattan)-Bronx-Richmond (Staten Island)-
Kings (Brooklyn)-Northern Queens-Southern Queens-
433 AM EDT Tue Aug 4 2020

...FLASH FLOOD WATCH REMAINS IN EFFECT THROUGH LATE TONIGHT...

The Flash Flood Watch continues for

* Portions of southern Connecticut, northeast New Jersey, and 
  southeast New York, including the following areas, in southern 
  Connecticut, Northern Fairfield and Northern New Haven. In 
  northeast New Jersey, Eastern Bergen, Eastern Essex, Eastern 
  Passaic, Eastern Union, Hudson, Western Bergen, Western Essex, 
  Western Passaic, and Western Union. In southeast New York, 
  Bronx, Kings (Brooklyn), New York (Manhattan), Northern 
  Queens, Northern Westchester, Orange, Putnam, Richmond (Staten 
  Island), Rockland, Southern Queens, and Southern Westchester. 

* Through late tonight

* Tropical Storm Isaias will track through the area today. A total 
  of 1 to 3 inches of rain will be possible with locally higher 
  amounts of up to 5 inches. Torrential downpours with multiple 
  rounds of heavy showers will allow for excessive runoff and 
  therefore would cause flash flooding in low lying, urban and 
  poor drainage areas. Some rivers and streams across the path of 
  the heavier rainfall axis could experience minor to moderate 
  rises resulting in possible road closures and inundation of 
  structures near the streams. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A Flash Flood Watch means that conditions may develop that lead
to flash flooding. Flash flooding is a very dangerous situation.
You should monitor later forecasts and be prepared to take action
should flash flood warnings be issued.

&&

$$
672 
WGUS61 KOKX 041915
FFAOKX

Flood Watch
National Weather Service New York NY
315 PM EDT Tue Aug 4 2020


CTZ005-006-NJZ002-004-006-103>108-NYZ067>075-176-178-042015-
/O.CAN.KOKX.FF.A.0002.000000T0000Z-200805T1000Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Northern Fairfield-Northern New Haven-Western Passaic-
Eastern Passaic-Hudson-Western Bergen-Eastern Bergen-
Western Essex-Eastern Essex-Western Union-Eastern Union-Orange-
Putnam-Rockland-Northern Westchester-Southern Westchester-
New York (Manhattan)-Bronx-Richmond (Staten Island)-
Kings (Brooklyn)-Northern Queens-Southern Queens-
315 PM EDT Tue Aug 4 2020

...FLASH FLOOD WATCH IS CANCELLED...

The Flash Flood Watch for portions of southern Connecticut,
northeast New Jersey, and southeast New York has been cancelled.
The heaviest rain continues to move off to the north, and the
threat of flooding has ended across these areas.

$$

What forecasters said that day

The local office's own words before this flash flood watch went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS New York, NY wrote its last area forecast discussion before this flash flood watch went out at Aug 2, 3:02 PM EDT, 30 minutes earlier.

Area forecast discussion, Aug 2, 3:02 PM EDT, 30 minutes before
Area Forecast Discussion
National Weather Service New York NY
302 PM EDT Sun Aug 2 2020

.SYNOPSIS...
Low pressure system over the Great Lakes region moves northeast
into southern Canada. Warm front pushes north of Long Island
this afternoon followed by a cold front moving east into the
Lower Hudson Valley tonight. Front then stalls over the area
through Monday.

Impacts from Tropical Storm Isaias are possible Tuesday into
Tuesday night. As Isaias rides quickly northeast of the area on
Wednesday a cold front will push off to the east, followed by
building high pressure later next week.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Enhanced wording to mention thunderstorm features of gusty
winds, heavy rain and small hail. The slight risk of severe
thunderstorms covers Northeast NJ, much of NYC, Northern Nassau,
the Lower Hudson Valley and much of Southern CT. Damaging winds
main threat with large hail smaller threat. With the warm front
moving across and enhanced low level helicity with that
enhanced low level shear, an isolated tornado is possible as
well.

Mesoscale convective models are focusing mainly on Northeast
NJ, the Lower Hudson Valley and SW Connecticut for several
rounds of showers and thunderstorms going through the remainder
of the afternoon.

An upper level long wave trough over the Great Lakes region and
its associated surface low near the Ohio River Valley are the
main focal points for the days expected weather. Spurred on by
an 80 kt jet the surface low moves northeast into southern
Canada today. At the same time the elongated warm front moves
north into the forecast area through this afternoon. Some
showers have moved across parts of Northeast NJ and the Lower
Hudson Valley this morning. Additional showers and thunderstorms
are expected later this afternoon once the front pushes north
through Long Island. With precipitable water values at and
around 2 inches heavy downpours could be an issue with the
convection this afternoon.

Areas not effected by rain will see temperatures rise into the
upper 80s and low 90s. This is particularly of note for areas
within northeast New Jersey where dew points will be elevated in
the low to mid 70s as well. As a result a Heat Advisory remains
in effect for northeast New Jersey and Staten Island NY as heat
indices will be approaching 100-102 degrees prior to the
expected rainfall. The limiting factor for this will be clouds
and convection keeping temperatures a little cooler than
expected. This could make a difference for interior parts of
Northeast NJ where convection is more likely with a possibility
that those parts of Northeast NJ may not get to 100 degree heat
index.

A moderate rip current risk is forecast for the ocean beaches
through this afternoon.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
Mesoscale convective models are still focusing mainly on
Northeast NJ, the Lower Hudson Valley and SW Connecticut for
some final rounds of showers and thunderstorms going through
the evening ahead of the cold front.

Potential for strong to severe thunderstorms along and ahead of the
cold front into the evening shows. Areas not impacted by the
showers earlier in the day could be primed for vigorous
convection with the boundary. Elevated CAPE values persist
between 1500-2000 J/kg providing enough instability for strong
thunderstorms and DCAPE values between 500-1000 J/kg hint at
strong downdraft gusts. Moreover, the 0-6km shear values around
30-40kts increases the possibility for severe storms. The
primary threats remain heavy rain and damaging winds though 0-3
km helicity values 150-200 m^2/s^2 between 22-03Z shows that
directional shear will exist within the warm sector of the low.
Overall a tornadic threat can not be ruled out particularly over
the Lower Hudson Valley. SPC still has much of our northwestern
counties within a Slight Risk of severe weather where the
severe threat is more probable.

As the low exists to the north Monday the cold front stalls and
transitions to a stationary boundary north of the city. Aloft
southwest upper level flow continues to advect moisture from the Mid
Atlantic. Monday evening could see heavy showers initiate off the
stationary front as a precursor to more rain expected into
Tuesday.

A high rip current risk is forecast for the ocean beaches on
Monday.

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
Potential impacts from Isaias then come into play moving through
Monday night, and certainly into Tuesday and Tuesday evening. One of
the biggest questions is how much heavier rainfall will break out
north and northeast ahead of the attendant system, and potentially
bringing parts of the area a PRE type of event which corresponds to
a swath of heavy rainfall working north and northeast ahead of the
main system. Therefore a swath of heavier rainfall could arrive
sooner than currently advertised anytime essentially during Monday
night as tropical moisture begins to ride north ahead of the frontal
boundary off to the west. In any event, Isaias will be off the SE
coast late Monday and Monday evening, then ride north before turning
northeast into the southern Mid Atlantic states by Tuesday morning.
From there the system is expected to turn more to the north-
northeast later Tuesday into Tuesday evening.

Right now the period of the heaviest rain is slated late Tuesday
morning into Tuesday afternoon and evening across much of the
region. The difficult part of the forecast will be with respect to
the alignment of the axis of heaviest rainfall and how this will
align with parts of the area that have more of an urban environment
where runoff issues would be magnified. The current thinking is a
wide swath for the potential of a 2 to 6 inch rainfall across the
area, with the eventually storm track ultimately deciding where the
axis of heaviest rainfall sets up.

The highest wind threat with regard to Isaias should correspond to
the eastern semicircle of the storm which places central and
eastern Long Island, along with eastern CT along the axis of
strongest winds. The timing for this looks to be during late in the
day on Tuesday and into Tuesday evening. One positive note is the
storm is expected to accelerate to the north and northeast into
Tuesday and Tuesday night. This may limit the duration of
stronger winds to some extent for coastal sections. The
preliminary guidance is suggesting the strongest winds may get
up to 45 mph sustained, with perhaps gusts to around 60 mph or
thereabouts across eastern sections of Long Island into Tuesday
evening. By Wednesday morning the center of circulation will be
pushing into New England and the winds across eastern sections
should shut off quickly.

As a cold front pushes east of the area on Wednesday a broad area of
high pressure will begin to gradually settle in from the west. The
high will settle over the region by Friday into Saturday. During
this time frame the weather is expected to remain predominantly dry,
with mainly a slight chance of a few late showers / storms. The
humidity will become noticeably lower into Thursday as the drier air
mass takes hold. The humidity will then begin to creep up closer to
Saturday as heights build slightly and the drier air mass undergoes
some modification.

&&

.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
A warm front lifting through the lower Hudson Valley and the NYC
metro area will continue northeastward today. A weak cool front
will enter the area tonight and dissipate.

As for winds: SSE to S flow along the coast mainly 10-15 kt
with gusts 20-25 kt, and speeds/gusts a few kt lower inland.
Winds veer SW to WSW 5-10 kt, and could see LLWS for a time
tonight at KISP/KGON as S winds increase to 35 kt aloft.

As for flight cat and wx: MVFR conds with some showers persist
mainly at the CT and Long Island terminals, with conds improving
to VFR in the NYC metro area where the warm front has passed.
Expect a showers/tstms to develop mainly NW of the NYC metros
with brief IFR vsby and strong wind gusts. This activity should
continue til about 00Z or 01Z. Mainly VFR tonight, except KGON
which should hang onto MVFR/tempo IFR this evening. Can't rule
out a few leftover showers/tstms this eve from the NYC metros
north/west.

.OUTLOOK FOR 18Z MONDAY THROUGH THURSDAY...
.Monday afternoon...mainly VFR.
.Monday night through Wednesday...Periodic showers and a chance
of tstms with MVFR to IFR conds. Impacts from Tropical Storm
Isaias may be likely Tuesday into Tuesday night, with heavy
rain, also strong winds mainly NYC metros/coast.
.Thursday and Friday...VFR.

&&

.MARINE...
Sub-SCA conditions are expected today although there are
expected to be SE gusts to near 20 kt with ocean seas of 3 to 4
ft.

As a front approaches the area tonight winds increases to 15-20 kt
with gusts around 25kts over the ocean. Seas should builds to 5-6 ft
tonight, then persist into Monday. A Small Craft Advisory is in
effect tonight into Monday.

Tropical storm conditions will become increasingly likely from
Tuesday afternoon into Tuesday evening across the ocean waters, then
further north for all of the non-ocean waters with perhaps the
exception of the western most near shore waters such as Long Island
Sound and NY Harbor. This will depend on the eventual track of
Isaias. In any event, tropical storm and gale conditions will take
place through Tuesday evening. Conditions will then improve quickly
from late Tuesday night into Wednesday morning from west to east.
Wave heights will briefly build to 10 to 15 ft out on the ocean
waters Tuesday night, then subside into Wednesday morning.

As early as Wednesday night even the ocean waters should settle down
to below SCA conditions for Wednesday night into Thursday with some
3-4 ft seas lingering out on the ocean.

&&

.HYDROLOGY...
Localized flooding possible with any thunderstorms today into
this evening.

There is the potential for more widespread heavy rainfall,
especially towards Monday night into Tuesday as Isaias begins to
come closer to the region. Additionally, the track of Isaias
will need to be monitored to narrow down the potential for minor
to moderate river flooding. Confidence in any moderate river
flooding remains low due to rainfall forecast uncertainty.

&&

.TIDES/COASTAL FLOODING...
Water levels across the south shore back bays of western Long Island
will yet again approach minor coastal flood benchmarks during the
evening high tide cycle. Based on recent performance of the
guidance, waters levels are expected to just touch or fall short of
minor benchmarks. The water levels are attributed to the upcoming
full moon on Monday and continued southerly swells. For Monday,
levels are forecast be about 1/2 ft lower and there is no flooding
concern.

Attention then shifts to Topical Storm Isaias. Based on the latest
track forecast from NHC, Isaias is forecast to pass near or just
west of NYC Tuesday evening. This would result in S-SE winds with
the potential for minor to moderate coastal flooding during the
Tuesday night high tide cycle.

&&

.EQUIPMENT...
NYC NOAA Weather Radio Station KWO-35 (162.55 MHz) is
undergoing its final stages of testing, and is operating at full
power.

&&

.OKX WATCHES/WARNINGS/ADVISORIES...
CT...None.
NY...High Rip Current Risk until 9 PM EDT this evening for NYZ075-
     080-081-178-179.
     Heat Advisory until 8 PM EDT this evening for NYZ074.
NJ...Heat Advisory until 8 PM EDT this evening for NJZ002-004-006-
     103>108.
MARINE...Small Craft Advisory from 6 PM this evening to 6 AM EDT Monday
     for ANZ355.
     Small Craft Advisory from 6 PM this evening to 6 PM EDT Monday
     for ANZ350.
     Small Craft Advisory from 6 PM this evening to noon EDT Monday
     for ANZ353.

&&

SYNOPSIS...JE/DJ
NEAR TERM...DJ/JM
SHORT TERM...DJ
LONG TERM...JE
AVIATION...Goodman
MARINE...DJ/JM
HYDROLOGY...DJ
TIDES/COASTAL FLOODING...
EQUIPMENT...
Hazardous weather outlook, Aug 2, 3:19 PM EDT, 13 minutes before
Hazardous Weather Outlook
National Weather Service New York NY
319 PM EDT Sun Aug 2 2020

NJZ002-004-103-104-031930-
Western Passaic-Eastern Passaic-Western Bergen-Eastern Bergen-
319 PM EDT Sun Aug 2 2020

...HEAT ADVISORY IN EFFECT UNTIL 8 PM EDT THIS EVENING...
...TORNADO WATCH 410 IN EFFECT UNTIL 10 PM EDT THIS EVENING...

This Hazardous Weather Outlook is for northeast New Jersey.

.DAY ONE...This afternoon and tonight.

Please listen to NOAA Weather Radio or go to weather.gov on the
Internet for more information about the following hazards.

   Tornado Watch.
   Heat Advisory.

.DAYS TWO THROUGH SEVEN...Monday through Saturday.

Please refer to the latest forecast on Isaias from the National
Hurricane Center. While it's too early to provide any specific
details on the impacts from the storm, it needs to be closely
monitored. Potential impacts during the Monday night to Wednesday
time period include heavy rainfall and gusty winds, coastal
flooding, and hazardous surf.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will likely be needed. Please safely report
significant weather conditions while following local, state, and CDC
guidelines.

CTZ005>007-009>011-NYZ067>071-031930-
Northern Fairfield-Northern New Haven-Northern Middlesex-
Southern Fairfield-Southern New Haven-Southern Middlesex-Orange-
Putnam-Rockland-Northern Westchester-Southern Westchester-
319 PM EDT Sun Aug 2 2020

...TORNADO WATCH 410 IN EFFECT UNTIL 10 PM EDT THIS EVENING...

This Hazardous Weather Outlook is for southern Connecticut and
southeast New York.

.DAY ONE...This afternoon and tonight.

Please listen to NOAA Weather Radio or go to weather.gov on the
Internet for more information about the following hazards.

   Tornado Watch.

.DAYS TWO THROUGH SEVEN...Monday through Saturday.

Please refer to the latest forecast on Isaias from the National
Hurricane Center. While it's too early to provide any specific
details on the impacts from the storm, it needs to be closely
monitored. Potential impacts during the Monday night to Wednesday
time period include heavy rainfall and gusty winds, coastal
flooding, and hazardous surf.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will likely be needed. Please safely report
significant weather conditions while following local, state, and CDC
guidelines.

NJZ006-105>108-NYZ074-031930-
Hudson-Western Essex-Eastern Essex-Western Union-Eastern Union-
Richmond (Staten Island)-
319 PM EDT Sun Aug 2 2020

...HEAT ADVISORY IN EFFECT UNTIL 8 PM EDT THIS EVENING...

This Hazardous Weather Outlook is for northeast New Jersey and
southeast New York.

.DAY ONE...This afternoon and tonight.

Please listen to NOAA Weather Radio or go to weather.gov on the
Internet for more information about the following hazards.

   Heat Advisory.

There is a chance for severe thunderstorm development into this
evening, with the highest chances near and to the north and west of
New York City. Damaging winds and heavy rain are the main threats,
however an isolated tornado can not be ruled out.

.DAYS TWO THROUGH SEVEN...Monday through Saturday.

Please refer to the latest forecast on Isaias from the National
Hurricane Center. While it's too early to provide any specific
details on the impacts from the storm, it needs to be closely
monitored. Potential impacts during the Monday night to Wednesday
time period include heavy rainfall and gusty winds, coastal
flooding, and hazardous surf.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be needed. Please safely report significant
weather conditions while following local, state, and CDC guidelines.

CTZ008-012-NYZ072-073-078-079-176-177-031930-
Northern New London-Southern New London-New York (Manhattan)-Bronx-
Northwestern Suffolk-Northeastern Suffolk-Northern Queens-
Northern Nassau-
319 PM EDT Sun Aug 2 2020

This Hazardous Weather Outlook is for southern Connecticut and
southeast New York.

.DAY ONE...This afternoon and tonight.

There is a chance for severe thunderstorm development into this
evening, with the highest chances near and to the north and west of
New York City. Damaging winds and heavy rain are the main threats,
however an isolated tornado can not be ruled out.

.DAYS TWO THROUGH SEVEN...Monday through Saturday.

Please refer to the latest forecast on Isaias from the National
Hurricane Center. While it's too early to provide any specific
details on the impacts from the storm, it needs to be closely
monitored. Potential impacts during the Monday night to Wednesday
time period include heavy rainfall and gusty winds, coastal
flooding, and hazardous surf.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be needed. Please safely report significant
weather conditions while following local, state, and CDC guidelines.

ANZ330-335-338-340-345-350-353-355-031930-
Long Island Sound East of New Haven CT/Port Jefferson NY-
Long Island Sound West of New Haven CT/Port Jefferson NY-
New York Harbor-Peconic and Gardiners Bays-
South Shore Bays from Jones Inlet through Shinnecock Bay-
Moriches Inlet NY to Montauk Point NY out 20 nm-
Fire Island Inlet NY to Moriches Inlet NY out 20 nm-
Sandy Hook NJ to Fire Island Inlet NY out 20 nm-
319 PM EDT Sun Aug 2 2020

This Hazardous Weather Outlook is for Atlantic coastal waters.

.DAY ONE...This afternoon and tonight.

There is a chance for severe thunderstorm development into this
evening, with wind gusts greater than 34kts possible. Damaging winds
and heavy rain are the main threats, however an isolated tornado can
not be ruled out.

.DAYS TWO THROUGH SEVEN...Monday through Saturday.

Refer to the latest forecast on Isaias from the National Hurricane
Center. The storm may bring tropical storm conditions to the waters,
especially across the eastern most waters during the Monday night to
Wednesday time period.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be needed. Please safely report significant
weather conditions while following local, state, and CDC guidelines.

NYZ075-080-081-178-179-031930-
Kings (Brooklyn)-Southwestern Suffolk-Southeastern Suffolk-
Southern Queens-Southern Nassau-
319 PM EDT Sun Aug 2 2020

...HIGH RIP CURRENT RISK IN EFFECT UNTIL 9 PM EDT THIS EVENING...

This Hazardous Weather Outlook is for southeast New York.

.DAY ONE...This afternoon and tonight.

Please listen to NOAA Weather Radio or go to weather.gov on the
Internet for more information about the following hazards.

   High Rip Current Risk.

There is a chance for severe thunderstorm development into this
evening, with the highest chances near and to the north and west of
New York City. Damaging winds and heavy rain are the main threats,
however an isolated tornado can not be ruled out.

.DAYS TWO THROUGH SEVEN...Monday through Saturday.

Please refer to the latest forecast on Isaias from the National
Hurricane Center. While it's too early to provide any specific
details on the impacts from the storm, it needs to be closely
monitored. Potential impacts during the Monday night to Wednesday
time period include heavy rainfall and gusty winds, coastal
flooding, and hazardous surf.

.SPOTTER INFORMATION STATEMENT...

Spotter activation may be needed. Please safely report significant
weather conditions while following local, state, and CDC guidelines.

The office that day

Everything else NWS New York, NY issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Aug 2, 12:31 PM EDTRip Current StatementOKXKings, Nassau, Queens, Suffolk3 days
Aug 2, 5:39 PM EDTSpecial Weather StatementOKXPutnam36 min
Aug 2, 6:00 PM EDTTropical Storm WatchOKXBronx, Kings, Nassau, New York, Orange, Putnam and 5 more17 hr
Aug 2, 6:39 PM EDTSpecial Weather StatementOKXOrange21 min

Nearby

Flash Flood Watches in New York, 2020Flash Flood Watches in New Jersey, 2020Flash Flood Watches in Connecticut, 2020Every flash flood watch in 2020

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.