Alert archive / Iowa / Flash Flood Warnings in 2011

Flash Flood Warning 32, NWS Des Moines, IA

July 15, 2011Cerro Gordo County, Worth County, Iowa

NWS Des Moines, IA issued this flash flood warning at Jul 15, 2011, 7:20 PM CDT for Cerro Gordo County, Worth County, Iowa. 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: Jul 15, 2011, 7:20 PM CDT (00:20 UTC)
Expired: Jul 15, 2011, 11:36 PM CDT
In force: 4 hr
Issued by: NWS Des Moines, IA
Area: Storm-based polygon
Flood severity: None

Counties Cerro Gordo County, IA, Worth County, IA

The radar

The Des Moines radar (KDMX), 170 km from the middle of the area, began a volume at 00:21 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

Minneapolis, MN (KMPX), launched 00:00Z, 0.3 hours before the alert went out and 188 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: 534 J/kg
Mixed-layer CIN: -207 J/kg
Mixed-layer LCL: 1464 m above ground
0-6 km bulk shear: 22 kt
0-1 km storm-relative helicity: 11 m²/s²
0-3 km storm-relative helicity: -9 m²/s²
Significant tornado parameter: 0.0
Supercell composite: -0.2

Open this sounding in Storm Lab

The text

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

679 
WGUS53 KDMX 160020
FFWDMX
IAC033-195-160630-
/O.NEW.KDMX.FF.W.0032.110716T0020Z-110716T0630Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
720 PM CDT FRI JUL 15 2011

THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  NORTHEASTERN CERRO GORDO COUNTY IN NORTH CENTRAL IOWA...
  SOUTHERN WORTH COUNTY IN NORTH CENTRAL IOWA...

* UNTIL 130 AM CDT SATURDAY

* AT 718 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED 
  THAT THUNDERSTORMS HAVE BEEN PRODUCING VERY HEAVY RAINFALL OVER 
  THE WARNED AREA. RAINFALL ESTIMATES ARE AS HIGH AS 3.5 TO 4.5 
  INCHES OVER THE PAST FEW HOURS.

* RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH FLOODING TO
  OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...MASON
  CITY AND MANLY.

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. TURN AROUND...DONT DROWN.

&&

LAT...LON 4328 9302 4309 9302 4308 9302 4311 9323
      4332 9343

$$

ZOGG

5 follow-up statements

902 
WGUS73 KDMX 160030
FFSDMX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
730 PM CDT FRI JUL 15 2011

IAC033-195-160630-
/O.CON.KDMX.FF.W.0032.000000T0000Z-110716T0630Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CERRO GORDO IA-WORTH IA-
730 PM CDT FRI JUL 15 2011

...FLASH FLOOD WARNING REMAINS IN EFFECT FOR SOUTHERN WORTH AND
NORTHEASTERN CERRO GORDO COUNTIES UNTIL 130 AM CDT SATURDAY...

AT 728 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED 
THAT THE THUNDERSTORMS WITH VERY HEAVY RAINFALL WERE EXITING THE 
WARNED AREA. THE THREAT OF FLASH FLOODING REMAINS HOWEVER. RAINFALL 
ESTIMATES ARE AS HIGH AS 3.5 TO 4.5 INCHES OVER THE PAST FEW HOURS.

RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH FLOODING TO
OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLASH  FLOODING INCLUDE...
MASON CITY AND MANLY. THE AREAS OF MOST CONCERN ARE NORTH OF A LINE 
THROUGH HANLONTOWN...ROCK FALLS AND NORA SPRINGS...AS WELL AS 
PORTIONS OF MASON CITY.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE
ROADWAY. FLOOD WATERS ARE USUALLY DEEPER THAN THEY APPEAR AND THE
WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO CROSS SAFELY. TURN
AROUND...DONT DROWN.

&&

LAT...LON 4328 9302 4309 9302 4308 9302 4311 9323
      4332 9343

$$

ZOGG

158 
WGUS73 KDMX 160133
FFSDMX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
833 PM CDT FRI JUL 15 2011

IAC033-195-160630-
/O.CON.KDMX.FF.W.0032.000000T0000Z-110716T0630Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CERRO GORDO IA-WORTH IA-
833 PM CDT FRI JUL 15 2011

...FLASH FLOOD WARNING REMAINS IN EFFECT FOR SOUTHERN WORTH AND
NORTHEASTERN CERRO GORDO COUNTIES UNTIL 130 AM CDT...

AT 830 PM CDT...FLASH FLOODING IS STILL LIKELY ACROSS PORTIONS OF 
SOUTHERN WORTH AND NORTHEASTERN CERRO GORDO COUNTIES. THE THREAT OF 
FLASH FLOODING REMAINS AS RAINFALL ESTIMATES ARE AS HIGH AS 3.5 TO 
4.5 INCHES OVER THE PAST FEW HOURS.

RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH FLOODING TO 
OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLASH FLOODING 
INCLUDE...JUST NORTH OF THE MASON CITY LIMITS AND MANLY. THE AREAS 
OF MOST CONCERN ARE NORTH OF A LINE THROUGH HANLONTOWN...ROCK FALLS 
AND NORA SPRINGS...AS WELL AS 
PORTIONS OF MASON CITY.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

DO NOT DRIVE YOUR VEHICLE INTO AREAS WHERE THE WATER COVERS THE
ROADWAY. FLOOD WATERS ARE USUALLY DEEPER THAN THEY APPEAR AND THE
WATER DEPTH MAY BE TOO GREAT TO ALLOW YOUR CAR TO CROSS SAFELY. TURN
AROUND...DONT DROWN.

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

&&

LAT...LON 4328 9302 4309 9302 4308 9302 4311 9323
      4332 9343

$$

VACHALEK

195 
WGUS73 KDMX 160235
FFSDMX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
935 PM CDT FRI JUL 15 2011

IAC033-195-160630-
/O.CON.KDMX.FF.W.0032.000000T0000Z-110716T0630Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CERRO GORDO IA-WORTH IA-
935 PM CDT FRI JUL 15 2011

...FLASH FLOOD WARNING REMAINS IN EFFECT FOR SOUTHERN WORTH AND
NORTHEASTERN CERRO GORDO COUNTIES UNTIL 130 AM CDT...

AT 931 PM CDT...LOCAL LAW ENFORCEMENT OFFICIALS REPORTED THAT RISING 
AND RAPIDLY MOVING WATER WAS OCCURRING IN THE GREENBELT AREA ALONG 
THE SHELL ROCK RIVER FROM NEAR ROCK FALLS TO NORA SPRINGS.  THIS 
AREA HAS BEEN CLOSED OFF BY CERRO GORDO COUNTY CONSERVATION 
OFFICIALS FOR THE REMAINDER OF THE NIGHT.  OTHER ROADS AND SMALL 
STREAMS MAY BE IMPACTED AS WELL FOR THE NEXT SEVERAL HOURS.

SOME LOCATIONS THAT WILL EXPERIENCE FLASH FLOODING INCLUDE...JUST 
NORTH OF THE MASON CITY LIMITS AND MANLY. THE AREAS OF MOST CONCERN 
ARE NORTH OF A LINE THROUGH HANLONTOWN...ROCK FALLS AND NORA SPRINGS.


PRECAUTIONARY/PREPAREDNESS ACTIONS...

BE ESPECIALLY CAUTIOUS AT NIGHT WHEN IT IS HARDER TO RECOGNIZE THE
DANGERS OF FLOODING. IF FLOODING IS OBSERVED...ACT QUICKLY. DO NOT
ENTER THE WATER. TURN AROUND AND MOVE UP TO HIGHER GROUND. DO NOT 
STAY IN AREAS SUBJECT TO FLOODING WHEN WATER BEGINS RISING. TURN 
AROUND...DONT DROWN.

&&

LAT...LON 4328 9302 4309 9302 4308 9302 4311 9323
      4332 9343

$$

VACHALEK

565 
WGUS73 KDMX 160336
FFSDMX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
1036 PM CDT FRI JUL 15 2011

IAC033-195-160630-
/O.CON.KDMX.FF.W.0032.000000T0000Z-110716T0630Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CERRO GORDO IA-WORTH IA-
1036 PM CDT FRI JUL 15 2011

...FLASH FLOOD WARNING REMAINS IN EFFECT FOR SOUTHERN WORTH AND
NORTHEASTERN CERRO GORDO COUNTIES UNTIL 130 AM CDT...

AT 1034 PM CDT...LOCAL LAW ENFORCEMENT OFFICIALS CONTINUED TO REPORT 
RISING AND RAPIDLY MOVING WATER IN THE GREENBELT AREA ALONG THE 
SHELL ROCK RIVER FROM NEAR ROCK FALLS TO NORA SPRINGS.  THIS AREA 
HAS BEEN CLOSED OFF BY CERRO GORDO COUNTY CONSERVATION OFFICIALS FOR 
THE REMAINDER OF THE NIGHT.  OTHER ROADS AND SMALL STREAMS MAY BE 
IMPACTED AS WELL FOR THE NEXT SEVERAL HOURS.

SOME LOCATIONS THAT WILL EXPERIENCE FLASH FLOODING INCLUDE...JUST 
NORTH OF THE MASON CITY LIMITS AND MANLY. THE AREAS OF MOST CONCERN 
ARE NORTH OF A LINE THROUGH HANLONTOWN...ROCK FALLS AND NORA SPRINGS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4328 9302 4309 9302 4308 9302 4311 9323
      4332 9343

$$

BEITLICH

873 
WGUS73 KDMX 160436
FFSDMX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
1136 PM CDT FRI JUL 15 2011

IAC033-195-160449-
/O.CAN.KDMX.FF.W.0032.000000T0000Z-110716T0630Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CERRO GORDO IA-WORTH IA-
1136 PM CDT FRI JUL 15 2011

...THE FLASH FLOOD WARNING THAT WAS IN EFFECT FOR SOUTHERN WORTH AND 
NORTHEASTERN CERRO GORDO COUNTIES WILL BE CANCELED AND REPLACED BY 
AN AREAL FLOOD WARNING AT 1134 PM CDT...

FLASH FLOODING FROM HEAVY RAIN HAS ENDED OVER THE WARNED AREA. EVEN 
THOUGH CONDITIONS ARE NOT WORSENING...GENERAL FLOODING REMAINS. IF 
FLOODING HAS BEEN OBSERVED...PLEASE REPORT IT TO YOUR LOCAL LAW 
ENFORCEMENT AGENCY.

LAT...LON 4328 9302 4309 9302 4308 9302 4311 9323
      4332 9343

$$

BEITLICH

The office that day

Everything else NWS Des Moines, IA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 15, 9:15 PM CDT	River Flood Warning	DMX	Black Hawk	6 days
Jul 15, 9:15 PM CDT	River Flood Warning	DMX	Black Hawk	5 days
Jul 15, 9:15 PM CDT	River Flood Warning	DMX	Black Hawk, Bremer, Butler	5 days
Jul 15, 11:25 PM CDT	Areal Flood Warning	DMX	Cerro Gordo, Worth	24 hr
Jul 16, 2:22 AM CDT	Flash Flood Warning	DMX	Cass	6 hr

Nearby

Flash Flood Warnings in Iowa, 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.