Alert archive / New York / Flash Flood Warnings in 2011

Flash Flood Warning 41, NWS New York, NY

September 28, 2011Suffolk County, New York

NWS New York, NY issued this flash flood warning at Sep 28, 2011, 4:43 PM EDT for Suffolk County, New York. It was in force for 4 hr. 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 28, 2011, 4:43 PM EDT (20:43 UTC)
Expired
Sep 28, 2011, 8:15 PM EDT
In force
4 hr
Issued by
NWS New York, NY
Area
Storm-based polygon
Flood severity
None

County Suffolk County, NY

The radar

The Brookhaven radar (KOKX), 11 km from the middle of the area, began a volume at 20:47 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, 8.7 hours before the alert went out and 11 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 2011-09-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 161 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 2011-09-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 67 square meters per square second.1939Sfc1 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
161 J/kg
Mixed-layer CIN
-30 J/kg
Mixed-layer LCL
567 m above ground
0-6 km bulk shear
10 kt
0-1 km storm-relative helicity
67 m²/s²
0-3 km storm-relative helicity
114 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.3

Open this sounding in Storm Lab

The text

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

180 
WGUS51 KOKX 282043
FFWOKX
NYC103-282245-
/O.NEW.KOKX.FF.W.0041.110928T2043Z-110928T2245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE NEW YORK NY
443 PM EDT WED SEP 28 2011

THE NATIONAL WEATHER SERVICE IN UPTON NY HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  SUFFOLK COUNTY IN SOUTHEAST NEW YORK...

* UNTIL 645 PM EDT...

* AT 436 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED   
FLASH FLOODING FROM A HEAVY SHOWERS OVER THE WARNED AREA. RAINFALL 
RATES OF 1 TO 1 1/2 INCHES PER HOUR ARE OCCURRING WITH THESE SHOWERS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL
CREEKS AND STREAMS...URBAN AREAS...HIGHWAYS...STREETS AND UNDERPASSES
AS WELL AS OTHER DRAINAGE AREAS AND LOW LYING SPOTS.

TO REPORT FLOODING...HAVE THE NEAREST LAW ENFORCEMENT AGENCY RELAY
YOUR REPORT TO THE NATIONAL WEATHER SERVICE FORECAST OFFICE IN UPTON
NY.

&&

LAT...LON 4072 7294 4073 7289 4076 7288 4076 7291
      4074 7293 4074 7296 4097 7313 4097 7277
      4099 7262 4104 7253 4096 7245 4099 7249
      4092 7261 4092 7247 4095 7245 4087 7237
      4071 7293

$$
4 follow-up statements
475 
WGUS71 KOKX 282128
FFSOKX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE NEW YORK NY
528 PM EDT WED SEP 28 2011

NYC103-282245-
/O.CON.KOKX.FF.W.0041.000000T0000Z-110928T2245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
SUFFOLK NY-
528 PM EDT WED SEP 28 2011

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 645 PM EDT FOR
SUFFOLK COUNTY...

AT 525 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO 
INDICATE HEAVY TROPICAL LIKE SHOWERS TRACKING NORTHWARD OVER THE 
WARNED AREA. THE AXIS OF HEAVY PRECIP HAS SHIFTED EASTWARD...BUT 
ANOTHER AREA OF HEAVY SHOWERS OVER THE ATLANTIC WILL MOVE INTO 
EASTERN SUFFOLK COUNTY BETWEEN EAST MORICHES AND HAMPTON BAYS AROUND 
6 PM AND ALSO TRACK TO THE NORTH. THIS ADDITIONAL RAINFALL WILL 
LIKELY CAUSE FLASH FLOODING. 

PRECAUTIONARY/PREPAREDNESS ACTIONS...

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL
CREEKS AND STREAMS...URBAN AREAS...HIGHWAYS...STREETS AND UNDERPASSES
AS WELL AS OTHER DRAINAGE AREAS AND LOW LYING SPOTS.

TO REPORT FLOODING...HAVE THE NEAREST LAW ENFORCEMENT AGENCY RELAY
YOUR REPORT TO THE NATIONAL WEATHER SERVICE FORECAST OFFICE IN UPTON
NY.

&&

LAT...LON 4071 7293 4072 7294 4073 7289 4076 7288
      4076 7291 4074 7293 4074 7295 4097 7302
      4097 7277 4099 7262 4104 7253 4096 7245
      4099 7249 4092 7261 4092 7247 4095 7245
      4087 7237

$$
967 
WGUS71 KOKX 282226
FFSOKX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE NEW YORK NY
626 PM EDT WED SEP 28 2011

NYC103-282245-
/O.CON.KOKX.FF.W.0041.000000T0000Z-110928T2245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
SUFFOLK NY-
626 PM EDT WED SEP 28 2011

...A FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 645 PM EDT FOR
SUFFOLK COUNTY...

AT 620 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO 
INDICATE A LARGE AREA OF HEAVY TROPICAL LIKE SHOWERS MOVING 
NORTHWARDS ACROSS EASTERN SUFFOLK COUNTY FROM A LINE EAST OF SHIRLEY 
AND SOUND BEACH TO SOUTHAMPTON AND PECONIC. RAINFALL RATES REMAIN 
BETWEEN 1 AND 1 1/2 INCHES PER HOUR. THIS ADDITIONAL RAINFALL IS 
LIKELY CAUSING FLASH FLOODING WITHIN THE WARNED AREA.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL
CREEKS AND STREAMS...URBAN AREAS...HIGHWAYS...STREETS AND UNDERPASSES
AS WELL AS OTHER DRAINAGE AREAS AND LOW LYING SPOTS.

TO REPORT FLOODING...HAVE THE NEAREST LAW ENFORCEMENT AGENCY RELAY
YOUR REPORT TO THE NATIONAL WEATHER SERVICE FORECAST OFFICE IN UPTON
NY.

&&

LAT...LON 4082 7253 4073 7286 4097 7291 4097 7277
      4099 7262 4104 7253 4096 7245 4099 7249
      4092 7261 4092 7247 4095 7245 4087 7237

$$
540 
WGUS51 KOKX 282237
FFWOKX
NYC103-290015-
/O.EXT.KOKX.FF.W.0041.000000T0000Z-110929T0015Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE NEW YORK NY
637 PM EDT WED SEP 28 2011

THE NATIONAL WEATHER SERVICE IN UPTON NY HAS EXTENDED THE

* FLASH FLOOD WARNING FOR...
  SUFFOLK COUNTY IN SOUTHEAST NEW YORK...

* UNTIL 815 PM EDT...

* AT 631 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A 
LARGE AREA OF HEAVY TROPICAL LIKE SHOWERS MOVING NORTHWARDS ACROSS 
EASTERN SUFFOLK COUNTY FROM A LINE EAST OF SHIRLEY AND SOUND BEACH 
TO SOUTHAMPTON AND PECONIC. RAINFALL RATES REMAIN BETWEEN 1 AND 1 
1/2 INCHES PER HOUR. BETWEEN 3/4 AND 1 INCH OF RAIN HAS ALREADY 
FALLEN ACCORDING TO MESONET SITES AND ANOTHER 1/2 INCH IS EXPECTED 
THROUGH 8 PM. THIS ADDITIONAL RAINFALL WILL LIKELY CAUSE FLASH 
FLOODING WITHIN THE WARNED AREA.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE FLOODING OF SMALL
CREEKS AND STREAMS...URBAN AREAS...HIGHWAYS...STREETS AND UNDERPASSES
AS WELL AS OTHER DRAINAGE AREAS AND LOW LYING SPOTS.

TO REPORT FLOODING...HAVE THE NEAREST LAW ENFORCEMENT AGENCY RELAY
YOUR REPORT TO THE NATIONAL WEATHER SERVICE FORECAST OFFICE IN UPTON
NY.

&&

LAT...LON 4082 7253 4073 7286 4097 7291 4097 7277
      4099 7262 4104 7253 4096 7245 4099 7249
      4092 7261 4092 7247 4095 7245 4087 7237

$$
710 
WGUS71 KOKX 290016
FFSOKX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE NEW YORK NY
816 PM EDT WED SEP 28 2011

NYC103-290025-
/O.EXP.KOKX.FF.W.0041.000000T0000Z-110929T0015Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
SUFFOLK NY-
816 PM EDT WED SEP 28 2011

...THE FLASH FLOOD WARNING HAS EXPIRED FOR SUFFOLK COUNTY...

THE HEAVY RAIN HAS MOVED EAST OF THE WARNED AREA...THEREFORE THE 
WARNING HAS BEEN ALLOWED TO EXPIRE.

LAT...LON 4082 7253 4073 7286 4097 7291 4097 7277
      4099 7262 4104 7253 4096 7245 4099 7249
      4092 7261 4092 7247 4095 7245 4087 7237

$$

The office that day

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

IssuedProductOfficeCountiesLasted
Sep 28, 4:09 AM EDTSmall Craft Advisory for Hazardous SeasOKX24 hr
Sep 28, 5:51 AM EDTSpecial Weather StatementOKXOrange2 hr
Sep 28, 5:54 AM EDTSpecial Weather StatementOKXOrange2 hr
Sep 28, 8:24 AM EDTAreal Flood AdvisoryOKXOrange71 min
Sep 28, 9:18 AM EDTFlash Flood WarningOKXOrange117 min
Sep 28, 3:28 PM EDTCoastal Flood StatementOKXBronx, Kings, Nassau, New York, Queens, Richmond and 2 more11 hr
Sep 28, 3:28 PM EDTCoastal Flood AdvisoryOKXBronx, Kings, Nassau, New York, Queens, Richmond and 2 more24 hr

Nearby

Flash Flood Warnings in New York, 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.