Alert archive / New York / Flash Flood Warnings in 2011

Flash Flood Warning 37, NWS New York, NY

September 23, 20114 counties in New York; Greater Bridgeport Planning Region, Connecticut

NWS New York, NY issued this flash flood warning at Sep 23, 2011, 3:13 PM EDT for 4 counties in New York; Greater Bridgeport Planning Region, Connecticut. It was in force for 103 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Sep 23, 2011, 3:13 PM EDT (19:13 UTC)
Expired
Sep 23, 2011, 4:56 PM EDT
In force
103 min
Issued by
NWS New York, NY
Area
Storm-based polygon
Flood severity
None

Counties Greater Bridgeport Planning Region, CT, Kings County, NY, Nassau County, NY, Queens County, NY, Westchester County, NY

The radar

The Brookhaven radar (KOKX), 79 km from the middle of the area, began a volume at 19:16 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, 7.2 hours before the alert went out and 79 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 2011-09-23Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 454 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Brookhaven, NY at 12:00Z on 2011-09-23The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 53 square meters per square second.19395878Sfc1 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
454 J/kg
Mixed-layer CIN
-7 J/kg
Mixed-layer LCL
434 m above ground
0-6 km bulk shear
36 kt
0-1 km storm-relative helicity
53 m²/s²
0-3 km storm-relative helicity
90 m²/s²
Significant tornado parameter
0.1
Supercell composite
1.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

230 
WGUS51 KOKX 231913
FFWOKX
CTC001-NYC047-059-081-119-232115-
/O.NEW.KOKX.FF.W.0037.110923T1913Z-110923T2115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE NEW YORK NY
313 PM EDT FRI SEP 23 2011

THE NATIONAL WEATHER SERVICE IN UPTON NY HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  WESTERN NASSAU COUNTY IN SOUTHEAST NEW YORK...
  WESTCHESTER COUNTY IN SOUTHEAST NEW YORK...
  FAIRFIELD COUNTY IN SOUTHERN CONNECTICUT...
  QUEENS COUNTY IN SOUTHEAST NEW YORK...
  KINGS (BROOKLYN) COUNTY IN SOUTHEAST NEW YORK...

* UNTIL 515 PM EDT...

* AT 307 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED   
MODERATE TO HEAVY RAIN MOVING ACROSS THE WARNING AREA. RAINFALL 
RATES OF ONE TO ONE AND A HALF INCHES ARE POSSIBLE. OVER TWO INCHES 
OF RAINFALL HAVE ALREADY FALLEN ACROSS THESE AREAS AND EXCESSIVE 
RUNOFF FROM THIS HEAVY RAINFALL WILL CAUSE FLOODING HIGHWAYS AND 
UNDERPASSES AND OTHER LOW LYING AREAS ARE SUBJECT TO FLOODING.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE 
ROADWAY. THE WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO CROSS 
SAFELY. MOVE TO HIGHER GROUND.

&&

LAT...LON 4075 7394 4080 7376 4088 7371 4085 7366
      4092 7360 4095 7366 4089 7380 4134 7382
      4138 7333 4102 7353 4100 7363 4096 7366
      4091 7359 4060 7376 4059 7383 4063 7376
      4065 7385 4063 7392 4059 7388 4058 7401

$$
1 follow-up statement
109 
WGUS71 KOKX 232056
FFSOKX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE NEW YORK NY
456 PM EDT FRI SEP 23 2011

CTC001-NYC047-059-081-119-232105-
/O.CAN.KOKX.FF.W.0037.000000T0000Z-110923T2115Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
KINGS (BROOKLYN) NY-QUEENS NY-FAIRFIELD CT-WESTCHESTER NY-NASSAU NY-
456 PM EDT FRI SEP 23 2011

...THE FLASH FLOOD WARNING HAS BEEN CANCELLED FOR WESTERN NASSAU...
WESTCHESTER...FAIRFIELD...QUEENS AND KINGS (BROOKLYN) COUNTIES...

HEAVY RAIN HAS MOVED OUT OF THE AREA AND THE IMMINENT THREAT FOR 
FLASH FLOODING HAS ENDED. 

LAT...LON 4075 7394 4080 7376 4088 7371 4085 7366
      4092 7360 4095 7366 4089 7380 4134 7382
      4138 7333 4102 7353 4100 7363 4096 7366
      4091 7359 4060 7376 4059 7383 4063 7376
      4065 7385 4063 7392 4059 7388 4058 7401

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 23, 2:36 AM EDTMarine Dense Fog AdvisoryOKX8 hr
Sep 23, 2:37 AM EDTDense Fog AdvisoryOKXNassau, Orange, Putnam, Rockland, Suffolk, Westchester6 hr
Sep 23, 12:09 PM EDTAreal Flood AdvisoryOKXBronx, Kings, New York, Queens, Richmond111 min
Sep 23, 2:04 PM EDTAreal Flood AdvisoryOKXBronx, New York, Rockland, Westchester86 min
Sep 23, 4:05 PM EDTFlash Flood WarningOKXOrange, Putnam, Westchester57 min
Sep 23, 6:38 PM EDTAreal Flood WarningOKXOrange, Putnam, Rockland5 hr
Sep 23, 7:38 PM EDTAreal Flood AdvisoryOKXBronx, Kings, New York, Putnam, Queens, Richmond and 2 more3 hr
Sep 23, 3:45 PM EDTFlash Flood WarningOKXGreater Bridgeport Planning Region, Naugatuck Valley Planning Region2 hr

Nearby

Flash Flood Warnings in New York, 2011Flash Flood Warnings in Connecticut, 2011Every flash flood warning in 2011

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.