Alert archive / New York / Flash Flood Warnings in 2021

Flash Flood Warning 34, NWS New York, NY

August 27, 2021Richmond County, New York

NWS New York, NY issued this flash flood warning at Aug 27, 2021, 5:41 PM EDT for Richmond County, New York. It was in force for 2 hr. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: Aug 27, 2021, 5:41 PM EDT (21:41 UTC)
Expired: Aug 27, 2021, 7:45 PM EDT
In force: 2 hr
Issued by: NWS New York, NY
Area: Storm-based polygon
Flood severity: None

County Richmond County, NY

The radar

The Philadelphia radar (KDIX), 67 km from the middle of the area, began a volume at 21:41 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.

What was reported inside it

Time	Report	Where	Remark
Aug 27, 7:02 PM EDT	FLASH FLOOD	1 Ene Tottenville, NY	STATEN ISLAND RAILWAY TRAIN SERVICE SUSPENDED IN BOTH DIRECTIONS BETWEEN HUGUENOT AND TOTTENVILLE DUE TO FLOODED TRACKS.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Brookhaven, NY (KOKX), launched 12:00Z, 9.7 hours before the alert went out and 119 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 1159 J/kg
Mixed-layer CIN: -60 J/kg
Mixed-layer LCL: 1043 m above ground
0-6 km bulk shear: 17 kt
0-1 km storm-relative helicity: 19 m²/s²
0-3 km storm-relative helicity: 22 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted.

911 
WGUS51 KOKX 272141
FFWOKX
NYC085-272345-
/O.NEW.KOKX.FF.W.0034.210827T2141Z-210827T2345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service New York NY
541 PM EDT Fri Aug 27 2021

The National Weather Service in Upton has issued a

* Flash Flood Warning for...
  Richmond (Staten Island) County in southeastern New York...

* Until 745 PM EDT.

* At 541 PM EDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 1 and 2 inches of rain 
  have fallen. Additional rainfall amounts of 1 to 2 inches are 
  possible in the warned area. Flash flooding is ongoing or expected 
  to begin shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar.

  IMPACT...Flash flooding of small creeks and streams, urban
           areas, highways, streets and underpasses as well as
           other poor drainage and low-lying areas.

* Some locations that will experience flash flooding include...
  Huguenot, Tottenville, Oakwood, Annadale and Greenridge.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

&&

LAT...LON 4050 7426 4051 7426 4052 7425 4054 7425
      4055 7425 4056 7423 4056 7422 4057 7421
      4058 7405 4057 7405 4052 7413 4052 7414
      4052 7415 4049 7423 4049 7427 4049 7428
      4050 7428

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL...1-2 INCHES IN 1 HOUR

$$

NV

2 follow-up statements

496 
WGUS71 KOKX 272236
FFSOKX

Flash Flood Statement
National Weather Service New York NY
636 PM EDT Fri Aug 27 2021

NYC085-272345-
/O.CON.KOKX.FF.W.0034.000000T0000Z-210827T2345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Richmond (Staten Island) NY-
636 PM EDT Fri Aug 27 2021

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 745 PM EDT THIS 
EVENING FOR RICHMOND (STATEN ISLAND) COUNTY...

At 636 PM EDT, Doppler radar indicated thunderstorms producing heavy 
rain across the warned area. Between 2 and 3 inches of rain have 
fallen. Additional rainfall amounts up to 1 inch are possible in the 
warned area. Flash flooding is ongoing or expected to begin shortly.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Radar.

IMPACT...Flash flooding of small creeks and streams, urban areas,
         highways, streets and underpasses as well as other poor
         drainage and low-lying areas.

Some locations that will experience flash flooding include...
  Huguenot, Tottenville, Oakwood, Annadale and Greenridge.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

&&

LAT...LON 4050 7426 4051 7426 4052 7425 4054 7425
      4055 7425 4056 7423 4056 7422 4057 7421
      4058 7405 4057 7405 4052 7413 4052 7414
      4052 7415 4049 7423 4049 7427 4049 7428
      4050 7428

FLASH FLOOD...RADAR INDICATED

$$

NV

794 
WGUS71 KOKX 272337
FFSOKX

Flash Flood Statement
National Weather Service New York NY
737 PM EDT Fri Aug 27 2021

NYC085-272347-
/O.EXP.KOKX.FF.W.0034.000000T0000Z-210827T2345Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Richmond (Staten Island) NY-
737 PM EDT Fri Aug 27 2021

...FLASH FLOOD WARNING WILL EXPIRE AT 745 PM EDT THIS EVENING FOR 
RICHMOND (STATEN ISLAND) COUNTY...

Flood waters have receded. The heavy rain has ended. Flooding is no 
longer expected to pose a threat. Please continue to heed remaining 
road closures.

A Flash Flood Watch remains in effect until 200 AM EDT Sunday for a 
portion of southeast New York.

LAT...LON 4050 7426 4051 7426 4052 7425 4054 7425
      4055 7425 4056 7423 4056 7422 4057 7421
      4058 7405 4057 7405 4052 7413 4052 7414
      4052 7415 4049 7423 4049 7427 4049 7428
      4050 7428

$$

NV

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 27, 3:31 PM EDT	Special Weather Statement	OKX	New York, Queens	44 min
Aug 27, 3:38 PM EDT	Small Craft Advisory	OKX		42 hr
Aug 27, 3:40 PM EDT	Areal Flood Advisory	OKX	Kings, New York, Queens, Richmond	3 hr
Aug 27, 3:58 PM EDT	Flash Flood Warning	OKX	Kings, Richmond	2 hr
Aug 27, 4:02 PM EDT	Special Marine Warning	OKX		118 min
Aug 27, 4:16 PM EDT	Special Weather Statement	OKX	Kings	44 min
Aug 27, 4:29 PM EDT	Areal Flood Advisory	OKX	Bronx, New York	17 min
Aug 27, 4:46 PM EDT	Flash Flood Warning	OKX	Bronx, New York, Queens	89 min
Aug 27, 4:50 PM EDT	Special Weather Statement	OKX	Richmond	55 min
Aug 27, 4:56 PM EDT	Areal Flood Advisory	OKX	Richmond	94 min
Aug 27, 5:00 PM EDT	Special Weather Statement	OKX	New York	60 min
Aug 27, 5:09 PM EDT	Special Weather Statement	OKX	Bronx	66 min
Aug 27, 5:11 PM EDT	Special Weather Statement	OKX	Richmond	49 min

Nearby

Flash Flood Warnings in New York, 2021 Every flash flood warning in 2021

Sources

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