Alert archive / South Dakota / Flash Flood Warnings in 2012

Flash Flood Warning 15, NWS Sioux Falls, SD

June 20, 2012Beadle County, Jerauld County, South Dakota

NWS Sioux Falls, SD issued this flash flood warning at Jun 20, 2012, 12:22 AM CDT for Beadle County, Jerauld 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: Jun 20, 2012, 12:22 AM CDT (05:22 UTC)
Expired: Jun 20, 2012, 4:30 AM CDT
In force: 4 hr
Issued by: NWS Sioux Falls, SD
Area: Storm-based polygon
Flood severity: None

Counties Beadle County, SD, Jerauld County, SD

The radar

The Aberdeen radar (KABR), 134 km from the middle of the area, began a volume at 05:22 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, 5.4 hours before the alert went out and 72 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: 322 J/kg
Mixed-layer CIN: -368 J/kg
Mixed-layer LCL: 663 m above ground
0-6 km bulk shear: 66 kt
0-1 km storm-relative helicity: 105 m²/s²
0-3 km storm-relative helicity: 206 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 7.2

Open this sounding in Storm Lab

The text

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

202 
WGUS53 KFSD 200522
FFWFSD
SDC005-073-200930-
/O.NEW.KFSD.FF.W.0015.120620T0522Z-120620T0930Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE SIOUX FALLS SD
1222 AM CDT WED JUN 20 2012

THE NATIONAL WEATHER SERVICE IN SIOUX FALLS HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  BEADLE COUNTY IN EAST CENTRAL SOUTH DAKOTA
  JERAULD COUNTY IN CENTRAL SOUTH DAKOTA

* UNTIL 430 AM CDT

* AT 1216 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR 
  INDICATED THUNDERSTORMS WITH VERY HEAVY RAINFALL ACROSS THE 
  WARNED AREA. AN ESTIMATED ONE TO TWO INCHES OF RAIN HAS ALREADY 
  FALLEN FROM JUST SOUTH OF HURON TOWARDS ALPENA TO WEST OF 
  WESSINGTON SPRINGS. AN ADDITIONAL ONE TO THREE INCHES WILL BE 
  POSSIBLE

* RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH FLOODING TO
  OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLOODING INCLUDE...
  HURON...ALPENA...HITCHCOCK...LANE...VIRGIL...WESSINGTON SPRINGS AND
  WOLSEY.

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.

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 4463 9785 4419 9828 4419 9833 4414 9833
      4394 9846 4394 9893 4403 9893 4420 9879
      4421 9871 4430 9871 4463 9844

$$
WEISSER

1 follow-up statement

952 
WGUS73 KFSD 200619
FFSFSD

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE SIOUX FALLS SD
119 AM CDT WED JUN 20 2012

SDC005-073-200930-
/O.CON.KFSD.FF.W.0015.000000T0000Z-120620T0930Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
JERAULD SD-BEADLE SD-
119 AM CDT WED JUN 20 2012

...FLASH FLOOD WARNING REMAINS IN EFFECT FOR BEADLE AND JERAULD
COUNTIES UNTIL 430 AM CDT...

AT 115 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED
THUNDERSTORMS WITH VERY HEAVY RAINFALL ACROSS THE WARNED AREA. 
DOPPLER RADAR ESTIMATED TWO TO FOUR INCHES OF RAINFALL FROM JUST 
SOUTH OF HURON TO AROUND ALPENA AND WESSINGTON SPRINGS. AN 
ADDITIONAL ONE TO TWO INCHES IS STILL POSSIBLE. THE HEAVIEST RAIN 
OVER THE NEXT HOUR WILL BE IN THE ALPENA AREA. 

SLOW MOVING THUNDERSTORMS ARE PRODUCING VERY HEAVY RAINFALL IN THE
WARNED AREA. RUNOFF FROM THIS EXCESSIVE RAINFALL WILL CAUSE FLASH
FLOODING TO OCCUR. SOME LOCATIONS THAT WILL EXPERIENCE FLOODING
INCLUDE...HURON...ALPENA...HITCHCOCK...LANE...VIRGIL...WESSINGTON
SPRINGS AND WOLSEY.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

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 4463 9785 4419 9828 4419 9833 4414 9833
      4394 9846 4394 9893 4403 9893 4420 9879
      4421 9871 4430 9871 4463 9844

$$

WEISSER

Nearby

Flash Flood Warnings in South Dakota, 2012 Every flash flood warning in 2012

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.