Alert archive / South Dakota / Flash Flood Warnings in 2012

Flash Flood Warning 3, NWS Aberdeen, SD

June 20, 2012Codington County, South Dakota

NWS Aberdeen, SD issued this flash flood warning at Jun 20, 2012, 2:11 AM CDT for Codington County, South Dakota. It was in force for 5 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
Jun 20, 2012, 2:11 AM CDT (07:11 UTC)
Expired
Jun 20, 2012, 6:47 AM CDT
In force
5 hr
Issued by
NWS Aberdeen, SD
Area
Storm-based polygon
Flood severity
None

County Codington County, SD

The radar

The Aberdeen radar (KABR), 112 km from the middle of the area, began a volume at 07:11 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
Jun 20, 2:15 AM CDTFLASH FLOODWatertown, SDSTREET FLOODING...RADAR ESTIMATING 3 TO 4 INCHES OF RAINFALL IN LESS THAN TWO HOURS
Jun 20, 2:25 AM CDTFLASH FLOODWatertown, SDINTERSECTION OF HWY 20 AND 3RD AVENUE NORTH AS WELL AS SEVERAL OTHER LOCATIONS ON HWY 20 HAVE WATER RUNNING ABOVE CURB LINE AND RUNNING OVER THE ROAD
Jun 20, 2:30 AM CDTFLASH FLOODWatertown, SDWATER IS RUNNING OVER CURB LINE ON HWY 212 BY PERKINS...ALSO BUDGET ONE HOTEL AT INTERSECTION OF HWY 212 AND 81 HAS 8 TO 10 ROOMS FLOODED

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

The nearest sounding before it

Aberdeen, SD (KABR), launched 00:00Z, 7.2 hours before the alert went out and 95 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 2012-06-20Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 322 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, Aberdeen, SD at 00:00Z on 2012-06-20The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 105 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
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.

023 
WGUS53 KABR 200711
FFWABR
SDC029-201300-
/O.NEW.KABR.FF.W.0003.120620T0711Z-120620T1300Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE ABERDEEN SD
211 AM CDT WED JUN 20 2012

THE NATIONAL WEATHER SERVICE IN ABERDEEN HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  CENTRAL CODINGTON COUNTY IN NORTHEAST SOUTH DAKOTA...

* UNTIL 800 AM CDT

* AT 209 AM CDT...LOCAL LAW ENFORCEMENT OFFICIALS REPORTED FLASH     
  FLOODING ACROSS THE WARNED AREA...TO INCLUDE WITHIN THE CITY OF    
  WATERTOWN.  

* SOME LOCATIONS THAT COULD EXPERIENCE FLOODING INCLUDE...
  WATERTOWN...DAKOTA SIOUX CASINO...RAUVILLE AND SANDY SHORE STATE
  PARK.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

ADDITIONAL RAINFALL AMOUNTS OF 1 TO 2 INCHES ARE POSSIBLE IN THE 
WARNED AREA.

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.

&&

LAT...LON 4501 9732 4501 9700 4482 9700 4483 9731

$$
CONNELLY
2 follow-up statements
807 
WGUS73 KABR 200814
FFSABR

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE ABERDEEN SD
314 AM CDT WED JUN 20 2012

SDC029-201300-
/O.CON.KABR.FF.W.0003.000000T0000Z-120620T1300Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CODINGTON SD-
314 AM CDT WED JUN 20 2012

...FLASH FLOOD WARNING REMAINS IN EFFECT FOR CENTRAL CODINGTON COUNTY
UNTIL 800 AM CDT...

AT 310 AM CDT...THE CITY OF WATERTOWN HAD RECIEVED OVER 3 INCHES OF 
RAIN...LEADING TO FLOODING FOR PORTIONS OF THE CITY.

SOME LOCATIONS THAT WILL EXPERIENCE FLASH FLOODING INCLUDE...
WATERTOWN...DAKOTA SIOUX CASINO...RAUVILLE AND SANDY SHORE STATE
PARK.

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 4501 9732 4501 9700 4482 9700 4483 9731

$$
CONNELLY
247 
WGUS73 KABR 201147
FFSABR

FLASH FLOOD STATEMENT
NATIONAL WEATHER SERVICE ABERDEEN SD
647 AM CDT WED JUN 20 2012

SDC029-201158-
/O.CAN.KABR.FF.W.0003.000000T0000Z-120620T1300Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
CODINGTON SD-
647 AM CDT WED JUN 20 2012

...THE FLASH FLOOD WARNING THAT WAS IN EFFECT FOR CENTRAL CODINGTON
COUNTY 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 4501 9732 4501 9700 4482 9700 4483 9731

$$
CONNELLY

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 19, 11:42 PM CDTSevere Thunderstorm WarningABRBuffalo, Lyman63 min
Jun 20, 2:28 AM CDTFlash Flood WarningABRCodington, Grant4 hr
Jun 20, 2:51 AM CDTFlash Flood WarningABRGrant, Roberts4 hr

Nearby

Flash Flood Warnings in South Dakota, 2012Every 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.