Alert archive / Iowa / Flash Flood Warnings in 2011

Flash Flood Warning 8, NWS La Crosse, WI

July 15, 2011Howard County, Mitchell County, Iowa

NWS La Crosse, WI issued this flash flood warning at Jul 15, 2011, 5:49 PM CDT for Howard County, Mitchell County, Iowa. It was in force for 3 hr. 3 reports 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
Jul 15, 2011, 5:49 PM CDT (22:49 UTC)
Expired
Jul 15, 2011, 9:00 PM CDT
In force
3 hr
Issued by
NWS La Crosse, WI
Area
Storm-based polygon
Flood severity
None

Counties Howard County, IA, Mitchell County, IA

The radar

The La Crosse radar (KARX), 127 km from the middle of the area, began a volume at 22:49 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

TimeReportWhereRemark
Jul 15, 6:15 PM CDTHEAVY RAIN 2.83St. Ansgar, IA2 HOUR RAINFALL TOTAL.
Jul 15, 7:00 PM CDTHEAVY RAIN 4.25St. Ansgar, IARAINFALL TOTAL IS 2 AND A HALF HOUR TOTAL. WIDESPREAD RURAL FLOODING OCCURING.
Jul 15, 7:55 PM CDTHEAVY RAIN 3.85Osage, IARAINFALL TOTAL IS 3 HOUR AMOUNT.

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

The nearest sounding before it

Minneapolis, MN (KMPX), launched 12:00Z, 10.8 hours before the alert went out and 180 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, Minneapolis, MN at 12:00Z on 2011-07-15Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1183 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, Minneapolis, MN at 12:00Z on 2011-07-15The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 101 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
1183 J/kg
Mixed-layer CIN
-78 J/kg
Mixed-layer LCL
585 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
101 m²/s²
0-3 km storm-relative helicity
135 m²/s²
Significant tornado parameter
0.0
Supercell composite
3.9

Open this sounding in Storm Lab

The text

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

830 
WGUS53 KARX 152249
FFWARX
IAC089-131-160200-
/O.NEW.KARX.FF.W.0008.110715T2249Z-110716T0200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE LA CROSSE WI
549 PM CDT FRI JUL 15 2011

THE NATIONAL WEATHER SERVICE IN LA CROSSE HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  HOWARD COUNTY IN NORTHEAST IOWA...
  MITCHELL COUNTY IN NORTH CENTRAL IOWA...

* UNTIL 900 PM CDT

* THUNDERSTORMS WITH VERY HEAVY RAIN CONTINUE TO FALL ACROSS FAR
  NORTHERN IOWA. RAINFALL OF 3 INCHES IS POSSIBLE WHICH WILL LEAD
  TO WATER RELATED PROBLEMS. ROADS COULD BE WASHED OUT AND PONDING
  IN FIELDS IS EXPECTED.

* RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH FLOODING TO
  OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
  CRESCO...OSAGE...ELMA...LIME SPRINGS...PROTIVIN...RICEVILLE...
  ST ANSGAR AND STACYVILLE.

LAT...LON 4350 9303 4350 9209 4322 9208 4321 9302

$$

SHEA
3 follow-up statements
239 
WGUS73 KARX 160005
FFSARX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE LA CROSSE WI
705 PM CDT FRI JUL 15 2011

IAC089-131-160200-
/O.CON.KARX.FF.W.0008.000000T0000Z-110716T0200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
MITCHELL IA-HOWARD IA-
705 PM CDT FRI JUL 15 2011

...FLASH FLOOD WARNING REMAINS IN EFFECT FOR HOWARD AND MITCHELL
COUNTIES UNTIL 900 PM CDT...

AT 701 PM CDT...LOCAL LAW ENFORCEMENT OFFICIALS REPORTED 
THUNDERSTORMS WITH VERY HEAVY RAINFALL ACROSS THE WARNED AREA. TWO 
AND ONE HALF INCHES OF RAIN HAS BEEN REPORTED SO FAR IN OSAGE. LOOK 
FOR ANOTHER 1 TO 2 INCHES OF RAINFALL THROUGH 800 PM AS ADDITIONAL 
THUNDERSTORMS MOVE ACROSS THE WARNED AREA.  

RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH FLOODING TO
OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
CRESCO...OSAGE...ELMA...LIME SPRINGS...RICEVILLE...ST. ANSGAR AND 
STACYVILLE.

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.

&&

LAT...LON 4350 9303 4350 9209 4322 9208 4321 9302

$$

JW
042 
WGUS73 KARX 160058
FFSARX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE LA CROSSE WI
758 PM CDT FRI JUL 15 2011

IAC089-131-160200-
/O.CON.KARX.FF.W.0008.000000T0000Z-110716T0200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
MITCHELL IA-HOWARD IA-
758 PM CDT FRI JUL 15 2011

...FLASH FLOOD WARNING REMAINS IN EFFECT FOR HOWARD AND MITCHELL
COUNTIES UNTIL 900 PM CDT...

AT 751 PM CDT...WEATHER SPOTTERS REPORTED THUNDERSTORMS WITH VERY 
HEAVY RAINFALL ACROSS THE WARNED AREA. TRAINED SPOTTERS REPORTED 4 
AND A QUARTER INCHES OF RAINFALL IN 2 AND A HALF HOURS IN ST. 
ANSGAR. THE THUNDERSTORMS HAVE TAPERED OFF WITH LIGHT ADDITIONAL 
RAINFALL AMOUNTS EXPECTED THROUGH 900 PM.   

RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH FLOODING TO
OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
CRESCO...OSAGE...ELMA...LIME SPRINGS...RICEVILLE...ST. ANSGAR AND
STACYVILLE.

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.

&&

LAT...LON 4350 9303 4350 9209 4322 9208 4321 9302

$$

JW
663 
WGUS73 KARX 160155
FFSARX

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE LA CROSSE WI
855 PM CDT FRI JUL 15 2011

IAC089-131-160210-
/O.EXP.KARX.FF.W.0008.000000T0000Z-110716T0200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
MITCHELL IA-HOWARD IA-
855 PM CDT FRI JUL 15 2011

...THE FLASH FLOOD WARNING THAT WAS IN EFFECT FOR HOWARD AND MITCHELL
COUNTIES WILL BE ALLOWED TO EXPIRE AT 900 PM CDT...

EXCESS RUNOFF FROM HEAVY RAIN HAS ENDED OVER THE WARNED AREA AND 
PREVIOUS STREET FLOODING HAS IMPROVED. IF FLOODING HAS BEEN 
OBSERVED...PLEASE REPORT IT TO YOUR LOCAL LAW ENFORCEMENT AGENCY.

LAT...LON 4350 9303 4350 9209 4322 9208 4321 9302

$$

The office that day

Everything else NWS La Crosse, WI issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 15, 3:57 AM CDTExcessive Heat WatchARXAllamakee, Chickasaw, Clayton, Fayette, Floyd, Howard and 2 more36 hr

Nearby

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