Alert archive / Connecticut / Flash Flood Warnings in 2011

Flash Flood Warning 23, NWS New York, NY

August 14, 2011Naugatuck Valley Planning Region, Connecticut

NWS New York, NY issued this flash flood warning at Aug 14, 2011, 11:45 PM EDT for Naugatuck Valley Planning Region, Connecticut. It was in force for 73 min. 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 14, 2011, 11:45 PM EDT (03:45 UTC)
Expired: Aug 15, 2011, 12:58 AM EDT
In force: 73 min
Issued by: NWS New York, NY
Area: Storm-based polygon
Flood severity: None

County Naugatuck Valley Planning Region, CT

The radar

The Brookhaven radar (KOKX), 46 km from the middle of the area, began a volume at 03:44 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 15, 12:15 AM EDT	FLASH FLOOD	Oronoque, CT	FLOODING ALONG MAIN STREET AND RIVER ROAD. ROAD CLOSED.

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 00:00Z, 3.8 hours before the alert went out and 46 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: 117 J/kg
Mixed-layer CIN: -31 J/kg
Mixed-layer LCL: 667 m above ground
0-6 km bulk shear: 16 kt
0-1 km storm-relative helicity: 73 m²/s²
0-3 km storm-relative helicity: 169 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.1

Open this sounding in Storm Lab

The text

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

223 
WGUS51 KOKX 150345
FFWOKX
CTC009-150545-
/O.NEW.KOKX.FF.W.0023.110815T0345Z-110815T0545Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE NEW YORK NY
1145 PM EDT SUN AUG 14 2011

THE NATIONAL WEATHER SERVICE IN UPTON NY HAS ISSUED A

* FLASH FLOOD WARNING CONTINUES FOR...
  SOUTHERN NEW HAVEN COUNTY IN SOUTHERN CONNECTICUT...

* UNTIL 145 AM EDT...

* AT 1140 PM EDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED  
MODERATE TO HEAVY RAINFALL MOVING NORTH ACROSS THE WARNING AREA. 
MAXIMUM HOURLY RAINFALL RATES OF UP TO 2.5 INCHES PER HOUR THAT   
WILL CAUSE SIGNIFICANT FLASH FLOODING. THE HEAVIEST RAIN WILL 
FALL ACROSS AREAS ALONG THE NAUGATUCK RIVER BASIN.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE
DANGERS OF FLOODING. IF FLASH FLOODING IS OBSERVED ACT QUICKLY. MOVE
UP TO HIGHER GROUND TO ESCAPE FLOOD WATERS. DO NOT STAY IN AREAS
SUBJECT TO FLOODING WHEN WATER BEGINS RISING.

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 4131 7299 4124 7298 4121 7301 4118 7311
      4119 7312 4120 7311 4123 7312 4126 7310
      4131 7307 4133 7311

$$

1 follow-up statement

203 
WGUS71 KOKX 150458
FFSOKX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE NEW YORK NY
1258 AM EDT MON AUG 15 2011

CTC009-150505-
/O.CAN.KOKX.FF.W.0023.000000T0000Z-110815T0545Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
NEW HAVEN CT-
1258 AM EDT MON AUG 15 2011

...THE FLASH FLOOD WARNING HAS BEEN CANCELLED FOR SOUTH CENTRAL NEW
HAVEN COUNTY...

THE STORM WHICH PROMPTED THE WARNING HAS SHIFTED NORTH OF THE 
WARNING AREA AND NO LONGER POSES A HEAVY RAIN THREAT. 

ADDITIONAL FLASH FLOODING IS NO LONGER EXPECTED. THE WARNING HAS 
THEREFORE BEEN CANCELLED.

ALTHOUGH HEAVY RAIN HAS SHIFTED NORTH OF THE AREA. THE FLASH FLOOD 
WARNING HAS THEREFORE BEEN CANCELLED.

LAT...LON 4131 7299 4124 7298 4121 7301 4118 7311
      4119 7312 4120 7311 4123 7312 4126 7310
      4131 7307 4133 7311

$$

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 14, 10:27 PM EDT	Areal Flood Advisory	OKX	Greater Bridgeport Planning Region, Naugatuck Valley Planning Region	48 min
Aug 14, 10:50 PM EDT	Flash Flood Warning	OKX	Naugatuck Valley Planning Region	55 min
Aug 15, 1:04 AM EDT	Flash Flood Warning	OKX	Greater Bridgeport Planning Region, Naugatuck Valley Planning Region	62 min
Aug 15, 9:09 AM EDT	Areal Flood Advisory	OKX	Lower Connecticut River Valley Planning Region, Southeastern Connecticut Planning Region	3 hr
Aug 15, 12:06 PM EDT	Areal Flood Advisory	OKX	Southeastern Connecticut Planning Region	78 min
Aug 15, 4:21 PM EDT	Areal Flood Advisory	OKX	Greater Bridgeport Planning Region	54 min

Nearby

Flash Flood Warnings in Connecticut, 2011 Every 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.