Alert archive / South Dakota / Flash Flood Warnings in 2001

Flash Flood Warning 11, NWS Sioux Falls, SD

August 29, 2001Charles Mix County, South Dakota

NWS Sioux Falls, SD issued this flash flood warning at Aug 29, 2001, 7:56 PM CDT for Charles Mix County, South Dakota. It was in force for 2 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline the Iowa Environmental Mesonet reconstructed for it; the warning itself named whole counties.

The facts

Issued: Aug 29, 2001, 7:56 PM CDT (00:56 UTC)
Expired: Aug 29, 2001, 10:00 PM CDT
In force: 2 hr
Issued by: NWS Sioux Falls, SD
Area: Whole counties; the outline is the Mesonet’s reconstruction

County Charles Mix County, SD

The radar

The Sioux Falls radar (KFSD), 140 km from the middle of the area, began a volume at 01:00 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, 0.9 hours before the alert went out and 210 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: 22 J/kg
Mixed-layer CIN: -433 J/kg
Mixed-layer LCL: 2046 m above ground
0-6 km bulk shear: 42 kt
0-1 km storm-relative helicity: -28 m²/s²
0-3 km storm-relative helicity: 190 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.5

Open this sounding in Storm Lab

The text

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

000 
WGUS53 KFSD 300057
FFWFSD
SDC023-300300-

BULLETIN - EAS ACTIVATION REQUESTED
FLASH FLOOD WARNING
NATIONAL WEATHER SERVICE SIOUX FALLS SD
756 PM CDT WED AUG 29 2001

THE NATIONAL WEATHER SERVICE IN SIOUX FALLS HAS ISSUED A

* FLASH FLOOD WARNING FOR...
  SOUTHEASTERN CHARLES MIX COUNTY IN SOUTH CENTRAL SOUTH DAKOTA

* UNTIL 1000 PM CDT

* AT 756 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED   
  THUNDERSTORMS WERE REPEATEDLY PRODUCING VERY HEAVY RAINFALL OVER   
  THE WARNED AREA.

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. VEHICLES CAUGHT IN RISING WATER SHOULD BE ABANDONED QUICKLY.
MOVE TO HIGHER GROUND.

LAT...LON 4296 9842 4285 9817 4314 9812 4317 9820

What forecasters said that day

The local office's own words before this flash flood warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Sioux Falls, SD wrote its last area forecast discussion before this flash flood warning went out at Aug 29, 2:55 PM CDT, 5 hours 1 minute earlier.

Area forecast discussion, Aug 29, 2:55 PM CDT, 5 hours 1 minute before

AREA FORECAST DISCUSSION FOR SOUTHEAST SD/SOUTHWEST MN/NORTHWEST IA
NATIONAL WEATHER SERVICE SIOUX FALLS SD
255 PM CDT WED AUG 29 2001

CDFNT WAS FM ERN ND THRU CNTRL SD IN WRN NE. LO ON FNT OVR CNTRL SD
WITH SOME SHWRS/TSTMS OVR SE ND MOVG TO THE NE. SECOND LO OVR WRN NE
BUT WITH STG MID LVL CAP TSTMS CAN NOT GET GOING. MDLS HAV NRN PART
OF FNT SAGGING S THRU ERN SD AND WRN MN THIS EVE AND THEN ENTIRE FNT
DRPG SE THRU NW IA AND NERN NE BY THU MRNG AS SFC LLOWS MOVG NE ALNG
FNT. SAT SHWG CLDS OVR ERN MT/WRN NE ASSOICATED WITH VORT MAX THAT
SHLD MOV ESE ALNG SD/ND BRDR TNGT. GOOD LO LVL MSTR IS ALSO BRING
PULLED N THRU WRN INTO ERN SD. AS CDFNT DROPS SE AND VORT MAX MOVES
IN FM W TSTMS SHLD DVLP THIS EVE OVR SE SD INTO SW MN...LOOK LIKE
BEST CHC OF TSTMS WILL BE ALNG AND TO N OF CDFNT THIS EVE IN NRN
PARTS OF CWA. IS ANYTHING SVR THIS LOOK TO BE THE BEST AREA FOR
DVLPMNT LATER THIS EVE WITH LLJ. FURTHER S IN NW IA THIS WILL
DVLP LTR TNGT AS CDFNT MOVES THRU. COOLR AND DRIER AIR MOVG IN BHND
FNT LATE TNGT INTO THU. MDLS DO DIFFER ON HOW MUCH PCP BHND FNT BUT
ONLY LEFT SOME MORNING SHWRS IN FAR SE ZNS. OTRW COOL DRY THU THRU
FRI NGT WITH SFC HI DRPG S IN NRN PLAINS AND RDG TO W. IN
EXTNDED...KEEPG IT DRY ON SAT BUT WITH RETURN FLOW AND SOME WAA AS
TROF MOVES THRU..WIL HAV A CHC OF TSTMS WRN ZNS SAT NGT SPRDG OVR
CWA ON SUN WITH SHWRS LINGERING LABOR DAY MRNG IN E. DRY IN FIRST
PART OF NEXT WEEK WITH SEASONAL TEMPS.

SD...NONE
WB

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 29, 7:08 PM CDT	Severe Thunderstorm Warning	FSD	McCook, Minnehaha	37 min
Aug 29, 7:29 PM CDT	Severe Thunderstorm Warning	FSD	Moody	31 min
Aug 29, 7:59 PM CDT	Severe Thunderstorm Warning	FSD	Moody	31 min
Aug 29, 8:45 PM CDT	Severe Thunderstorm Warning	FSD	Minnehaha	15 min
Aug 29, 9:04 PM CDT	Severe Thunderstorm Warning	FSD	McCook	26 min
Aug 29, 9:36 PM CDT	Flash Flood Warning	FSD	McCook, Minnehaha	114 min
Aug 29, 10:42 PM CDT	Severe Thunderstorm Warning	FSD	Charles Mix	18 min

Nearby

Flash Flood Warnings in South Dakota, 2001 Every flash flood warning in 2001

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.