Alert archive / South Dakota / Flash Flood Warnings in 2011

Flash Flood Warning 28, NWS Sioux Falls, SD

July 26, 2011Beadle County, Kingsbury County, South Dakota

NWS Sioux Falls, SD issued this flash flood warning at Jul 26, 2011, 3:17 AM CDT for Beadle County, Kingsbury County, South Dakota. 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 26, 2011, 3:17 AM CDT (08:17 UTC)
Expired
Jul 26, 2011, 7:09 AM CDT
In force
4 hr
Issued by
NWS Sioux Falls, SD
Area
Storm-based polygon
Flood severity
None

Counties Beadle County, SD, Kingsbury County, SD

The radar

The Sioux Falls radar (KFSD), 124 km from the middle of the area, began a volume at 08:19 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

Aberdeen, SD (KABR), launched 00:00Z, 8.3 hours before the alert went out and 73 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, Aberdeen, SD at 00:00Z on 2011-07-26Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Aberdeen, SD at 00:00Z on 2011-07-26The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -41 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
2164 m above ground
0-6 km bulk shear
38 kt
0-1 km storm-relative helicity
-41 m²/s²
0-3 km storm-relative helicity
83 m²/s²
Significant tornado parameter
0.0
Supercell composite
-0.0

Open this sounding in Storm Lab

The text

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

048 
WGUS53 KFSD 260817
FFWFSD
SDC005-077-261230-
/O.NEW.KFSD.FF.W.0028.110726T0817Z-110726T1230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE SIOUX FALLS SD
317 AM CDT TUE JUL 26 2011

THE NATIONAL WEATHER SERVICE IN SIOUX FALLS HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  EASTERN BEADLE COUNTY IN EAST CENTRAL SOUTH DAKOTA
  WESTERN KINGSBURY COUNTY IN EAST CENTRAL SOUTH DAKOTA

* UNTIL 730 AM CDT

* AT 310 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
  THUNDERSTORMS WITH VERY HEAVY RAINFALL SET TO RETURN ACROSS THE
  WARNED AREA. THIS AREA HAS ALREADY RECEIVED A RADAR ESTIMATED 
  3 TO 4 INCHES RAINFALL FROM EARLIER THUNDERSTORMS.

* RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH FLOODING TO
  OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
  IROQUOIS...AND SPECIFICALLY AREAS NEAR AND NORTH OF IROQUOIS ON
  THE MIDDLE AND SOUTH FORKS OF PEARL CREEK.

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. DO
NOT ENTER THE WATER. TURN AROUND AND MOVE UP TO HIGHER GROUND TO
ESCAPE FLOOD WATERS. DO NOT STAY IN AREAS SUBJECT TO FLOODING WHEN
WATER BEGINS RISING.

&&

LAT...LON 4446 9772 4432 9769 4433 9792 4445 9790

$$
2 follow-up statements
481 
WGUS73 KFSD 261017
FFSFSD

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
517 AM CDT TUE JUL 26 2011

SDC005-077-261230-
/O.CON.KFSD.FF.W.0028.000000T0000Z-110726T1230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
KINGSBURY SD-BEADLE SD-
517 AM CDT TUE JUL 26 2011

...FLASH FLOOD WARNING REMAINS IN EFFECT FOR EASTERN BEADLE AND
WESTERN KINGSBURY COUNTIES UNTIL 730 AM CDT...

AT 515 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
ESTIMATED RAINFALL TOTALS FROM 3 TO 5 INCHES OCCURRED IN A SMALL 
AREA MAINLY NEAR AND NORTH OF IROQUOIS. WHILE THE THREAT OF 
ADDITIONAL HEAVY RAINFALL HAS GENERALLY ENDED THIS MORNING...THE 
RUNOFF FROM EARLIER HEAVY RAINFALL WILL CONTINUE TO IMPACT MAINLY 
THE SOUTH AND MIDDLE FORKS OF PEARL CREEK.  

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.

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 4446 9772 4432 9769 4433 9792 4445 9790

$$

CHAPMAN
513 
WGUS73 KFSD 261209
FFSFSD

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
709 AM CDT TUE JUL 26 2011

SDC005-077-261224-
/O.CAN.KFSD.FF.W.0028.000000T0000Z-110726T1230Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
KINGSBURY SD-BEADLE SD-
709 AM CDT TUE JUL 26 2011

...THE FLASH FLOOD WARNING THAT WAS IN EFFECT FOR EASTERN BEADLE AND
WESTERN KINGSBURY COUNTIES IS CANCELLED...

EXCESS RUNOFF FROM HEAVY RAIN HAS ENDED OVER THE WARNED AREA. STREAMS
AND CREEKS IN THE WARNED AREA HAVE RECEDED OR WERE BEGINNING TO
RECEDE...ENDING THE FLOOD THREAT. IF FLOODING HAS BEEN OBSERVED...
PLEASE REPORT IT TO YOUR LOCAL LAW ENFORCEMENT AGENCY.

LAT...LON 4446 9772 4432 9769 4433 9792 4445 9790

$$

CHAPMAN

The office that day

Everything else NWS Sioux Falls, SD issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jul 25, 7:24 PM CDTSevere Thunderstorm WarningFSDMoody36 min
Jul 25, 7:53 PM CDTSevere Thunderstorm WarningFSDMinnehaha, Moody37 min
Jul 25, 8:23 PM CDTSevere Thunderstorm WarningFSDMinnehaha37 min
Jul 25, 8:53 PM CDTSevere Thunderstorm WarningFSDMinnehaha37 min
Jul 25, 9:04 PM CDTSevere Thunderstorm WarningFSDMoody41 min
Jul 25, 10:29 PM CDTSevere Thunderstorm WarningFSDLincoln, Turner31 min
Jul 25, 10:54 PM CDTSevere Thunderstorm WarningFSDTurner36 min

Nearby

Flash Flood Warnings in South Dakota, 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.