Alert archive / Iowa / Severe Thunderstorm Warnings in 1997
Severe Thunderstorm Warning 131, NWS Sioux Falls, SD
NWS Sioux Falls, SD issued this severe thunderstorm warning at Sep 8, 1997, 2:29 PM CDT for Lyon County, Iowa; Lincoln County, South Dakota. It was in force for 31 min. 1 report came from inside the area while it was in force.
The area
The counties it named, with what was reported inside it.
The facts
- Issued
- Sep 8, 1997, 2:29 PM CDT (19:29 UTC)
- Expired
- Sep 8, 1997, 3:00 PM CDT
- In force
- 31 min
- Issued by
- NWS Sioux Falls, SD
- Area
- Whole counties
Counties Lyon County, IA, Lincoln County, SD
The radar
The Sioux Falls radar (KFSD), 36 km from the middle of the area, began a volume at 19:30 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
| Time | Report | Where | Remark |
|---|---|---|---|
| Sep 8, 2:55 PM CDT | Hail 0.75 | Rock Rapids, IA |
NCEI Storm Data entries that began inside the alert's area while it was in force. Before 2003 the local storm report archive is thin, so this is the record of what happened rather than what was phoned in.
The nearest sounding before it
Omaha, NE (KOAX), launched 12:00Z, 7.5 hours before the alert went out and 224 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.
- Mixed-layer CAPE
- 2554 J/kg
- Mixed-layer CIN
- -42 J/kg
- Mixed-layer LCL
- 811 m above ground
- 0-6 km bulk shear
- 9 kt
- 0-1 km storm-relative helicity
- -31 m²/s²
- 0-3 km storm-relative helicity
- -18 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
000 TTAA00 KFSD 081929 RRA SVRFSD IAC119-SDC083-082000- BULLETIN - IMMEDIATE BROADCAST REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE SIOUX FALLS SD 229 PM CDT MON SEP 8 1997 * SEVERE THUNDERSTORM WARNING FOR LINCOLN COUNTY IN SOUTHEASTERN SOUTH DAKOTA LYON COUNTY IN NORTHWESTERN IOWA * UNTIL 300 PM CDT * SOME AREAS AFFECTED SHINDLER AROUND 230 PM CDT HARRISBURG AROUND 230 PM CDT GRANITE AROUND 230 PM CDT WORTHING AROUND 235 PM CDT LARCHWOOD AROUND 235 PM CDT KLONDIKE AROUND 240 PM CDT CANTON AROUND 245 PM CDT BELOIT AROUND 245 PM CDT INWOOD AROUND 250 PM CDT ALVORD AROUND 255 PM CDT * AT 227 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM IN THE VICINITY OF SIOUX FALLS MOVING SOUTHEAST AT 35 MPH. IF YOU ARE OUTDOORS...MOVE TO A PLACE OF SHELTER IMMEDIATELY IF A STORM APPROACHES. MOTORISTS SHOULD REMAIN ALERT FOR REDUCED VISIBILITIES DURING DOWNPOURS OF RAIN. STREETS MAY FLOOD QUICKLY. WILLIAMS
What forecasters said that day
The local office's own words before this severe thunderstorm 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 severe thunderstorm warning went out at Sep 8, 11:56 AM CDT, 2 hours 33 minutes earlier.
Area forecast discussion, Sep 8, 11:56 AM CDT, 2 hours 33 minutes before
SOUTHEAST SD/NORTHWEST IA/SOUTHWEST MN FORECAST DISCUSSION NATIONAL WEATHER SERVICE SIOUX FALLS SD 1150 AM CDT MON SEP 8 1997 FOG EPSIODE OVER...SO NOW THUNDERSTORMS BECOME THE MAIN CONCERN. WRN CWA GETTING CLOSE TO SFC BASED CONVECTIVE TMPS...AND EXTREMELY UNSTABLE. TSRA FORMING ALONG SFC CDFNT...AND ALSO BNDRY FM LAST NGT THRU NE/ECNTRL SD. ABR VWP EXHIBITING GUD SHEAR...AND FLOW FAVORABLE FOR SPLITTING CELLS. HAVE UPDATED TO INCREASE POPS CWAWIfDE. TEMPS ALSO NEEDED A SMALL BOOST SRN CWA...NOW HOPE LOW CLDS DISSIPATE IN TIME. .FSD...NONE CHAPMAN
In the hours before
Special weather statement, Sep 8, 11:04 AM CDT, 3 hours 25 minutes before
SIGNIFICANT WEATHER OUTLOOK NATIONAL WEATHER SERVICE SIOUX FALLS SD 1105 AM CDT MON SEP 8 1997 *** SIGNIFICANT WEATHER PERTAINS TO WEATHER ELEMENTS ASSOCIATED WITH THUNDERSTORMS. *** .SYNOPSIS...A STRONG UPPER LEVEL SYSTEM WILL DROP SOUTHEAST ACROSS SOUTH DAKOTA LATE THIS AFTERNOON AND TONIGHT. THE ASSOCIATED COLD FRONT WILL MOVE INTO NORTHWEST IOWA BY EARLY EVENING. THE ATMOSPHERE OVER THE AREA CONTINUES MOIST AND MODERATELY UNSTABLE... SO WITH HEATING OF THE DAY...SCATTERED THUNDERSTORMS ARE EXPECTED. PREFERRED LOCATION FOR DEVELOPMENT THIS AFTERNOON WILL BE ALONG THE COLD FRONT...AND ALSO ALONG A BOUNDARY FROM LAST NIGHTS CONVECTION LYING ACROSS EAST CENTRAL SOUTH DAKOTA AND SOUTHWEST MINNESOTA. RELATIVELY COLD AIR ALOFT MAY RESULT IN SOME SMALL HAIL IN STRONGER STORMS. SDZ038>040-050-052>071-MNZ071-072-080-081-089-090-097-098-IAZ001>003- 012>014-020>022-031-032-NEZ013-014-090500- AURORA-BEADLE-BON HOMME-BROOKINGS-BRULE-CHARLES MIX-CLAY-DAVISON- DOUGLAS-GREGORY-HANSON-HUTCHINSON-JERAULD-KINGSBURY-LAKE-LINCOLN- MC COOK-MINER-MINNEHAHA-MOODY-SANBORN-TURNER-UNION-YANKTON-COTTONWOOD- JACKSON-LINCOLN-LYON-MURRAY-NOBLES-PIPESTONE-ROCK-BUENA VISTA- CHEROKEE-CLAY-DICKINSON-IDA-LYON-O'BRIEN-OSCEOLA-PLYMOUTH-SIOUX- WOODBURY-DAKOTA-DIXON- INCLUDING THE CITIES OF...BROOKINGS...CHAMBERLAIN...HURON...MITCHELL... SIOUX FALLS...YANKTON...LUVERNE...PIPESTONE...SLAYTON...WORTHINGTON... LE MARS...ROCK RAPIDS...SIOUX CENTER...SIOUX CITY...SPENCER... SPIRIT LAKE...STORM LAKE 1105 AM CDT MON SEP 8 1997 FORECAST THROUGH MIDNIGHT: WIDELY SCATTERED THUNDERSTORMS WILL DEVELOP THIS AFTERNOON AND PUSH ACROSS THE AREA THROUGH THE EVENING. SOME STORMS MAY CONTAIN SMALL HAIL AND WINDS GUSTS TO 40 MILES AN HOUR...BUT SIGNIFICANT WEATHER IS NOT EXPECTED IN THIS AREA THROUGH MIDNIGHT. * SIGNIFICANT WEATHER: NONE * SPOTTER ACTIVATION: SPOTTER ACTIVATION IS NOT ANTICIPATED. CHAPMAN
Special weather statement, Sep 8, 11:05 AM CDT, 3 hours 24 minutes before
SIGNIFICANT WEATHER OUTLOOK NATIONAL WEATHER SERVICE SIOUX FALLS SD 1105 AM CDT MON SEP 8 1997 *** SIGNIFICANT WEATHER PERTAINS TO WEATHER ELEMENTS ASSOCIATED WITH THUNDERSTORMS. *** .SYNOPSIS...A STRONG UPPER LEVEL SYSTEM WILL DROP SOUTHEAST ACROSS SOUTH DAKOTA LATE THIS AFTERNOON AND TONIGHT. THE ASSOCIATED COLD FRONT WILL MOVE INTO NORTHWEST IOWA BY EARLY EVENING. THE ATMOSPHERE OVER THE AREA CONTINUES MOIST AND MODERATELY UNSTABLE... SO WITH HEATING OF THE DAY...SCATTERED THUNDERSTORMS ARE EXPECTED. PREFERRED LOCATION FOR DEVELOPMENT THIS AFTERNOON WILL BE ALONG THE COLD FRONT...AND ALSO ALONG A BOUNDARY FROM LAST NIGHTS CONVECTION LYING ACROSS EAST CENTRAL SOUTH DAKOTA AND SOUTHWEST MINNESOTA. RELATIVELY COLD AIR ALOFT MAY RESULT IN SOME SMALL HAIL IN STRONGER STORMS. SDZ038>040-050-052>071-MNZ071-072-080-081-089-090-097-098-IAZ001>003- 012>014-020>022-031-032-NEZ013-014-090500- AURORA-BEADLE-BON HOMME-BROOKINGS-BRULE-CHARLES MIX-CLAY-DAVISON- DOUGLAS-GREGORY-HANSON-HUTCHINSON-JERAULD-KINGSBURY-LAKE-LINCOLN- MC COOK-MINER-MINNEHAHA-MOODY-SANBORN-TURNER-UNION-YANKTON-COTTONWOOD- JACKSON-LINCOLN-LYON-MURRAY-NOBLES-PIPESTONE-ROCK-BUENA VISTA- CHEROKEE-CLAY-DICKINSON-IDA-LYON-OBRIEN-OSCEOLA-PLYMOUTH-SIOUX- WOODBURY-DAKOTA-DIXON- INCLUDING THE CITIES OF...BROOKINGS...CHAMBERLAIN...HURON...MITCHELL... SIOUX FALLS...YANKTON...LUVERNE...PIPESTONE...SLAYTON...WORTHINGTON... LE MARS...ROCK RAPIDS...SIOUX CENTER...SIOUX CITY...SPENCER... SPIRIT LAKE...STORM LAKE 1105 AM CDT MON SEP 8 1997 FORECAST THROUGH MIDNIGHT: WIDELY SCATTERED THUNDERSTORMS WILL DEVELOP THIS AFTERNOON AND PUSH ACROSS THE AREA THROUGH THE EVENING. SOME STORMS MAY CONTAIN SMALL HAIL AND WINDS GUSTS TO 40 MILES AN HOUR...BUT SIGNIFICANT WEATHER IS NOT EXPECTED IN THIS AREA THROUGH MIDNIGHT. * SIGNIFICANT WEATHER: NONE * SPOTTER ACTIVATION: SPOTTER ACTIVATION IS NOT ANTICIPATED. CHAPMAN
Special weather statement, Sep 8, 1:23 PM CDT, 1 hour 6 minutes before
SIGNIFICANT WEATHER OUTLOOK NATIONAL WEATHER SERVICE SIOUX FALLS SD 123 PM CDT MON SEP 8 1997 *** SIGNIFICANT WEATHER PERTAINS TO WEATHER ELEMENTS ASSOCIATED WITH THUNDERSTORMS. *** .SYNOPSIS...A COLD FRONT WILL MOVE ACROSS SOUTHEAST SOUTH DAKOTA...SOUTHWEST MINNESOTA...AND NORTHWEST IOWA THIS AFTERNOON AND EARLY EVENING. SDZ039-040-050-054>056-059>071-MNZ071-072-080-081-089-090-097-098- IAZ001>003-012>014-020>022-031-032-NEZ013-014-090500- BON HOMME-BROOKINGS-CHARLES MIX-CLAY-DAVISON-DOUGLAS-GREGORY-HANSON- HUTCHINSON-KINGSBURY-LAKE-LINCOLN-MC COOK-MINER-MINNEHAHA-MOODY- TURNER-UNION-YANKTON-COTTONWOOD-JACKSON-LINCOLN-LYON-MURRAY-NOBLES- PIPESTONE-ROCK-BUENA VISTA-CHEROKEE-CLAY-DICKINSON-IDA-LYON-OBRIEN- OSCEOLA-PLYMOUTH-SIOUX-WOODBURY-DAKOTA-DIXON- INCLUDING THE CITIES OF...BROOKINGS...MITCHELL...SIOUX FALLS... YANKTON...LUVERNE...PIPESTONE...SLAYTON...WORTHINGTON...LE MARS... ROCK RAPIDS...SIOUX CENTER...SIOUX CITY...SPENCER...SPIRIT LAKE... STORM LAKE 123 PM CDT MON SEP 8 1997 FORECAST THROUGH MIDNIGHT: AT 115 PM CDT STRONG AND SEVERE THUNDERSTORMS WERE OCCURING FROM 20 MILES SOUTHWEST OF MITCHELL NORTHEAST TO 20 MILES EAST OF WATERTOWN. THESE STORMS WILL MOVE SOUTHEAST AT ABOUT 25 MPH AND ARE EXPECTED INTO SIOUX CITY IOWA TO WORTHINGTON MINNESOTA LINE BY 6PM. * SIGNIFICANT WEATHER: WIND GUSTS TO 60 MPH. HAIL TO 1 INCH SIZE. RAINFALL RATES OF UP TO 2 INCHES PER HOUR. * SPOTTER ACTIVATION: SPOTTER ACTIVATION MAY BE NEEDED AFTER 1PM. SDZ038-052-053-057-058-090500- AURORA-BEADLE-BRULE-JERAULD-SANBORN- INCLUDING THE CITIES OF...CHAMBERLAIN...HURON 123 PM CDT MON SEP 8 1997 FORECAST THROUGH MIDNIGHT: SIGNIFICANT WEATHER IS NOT EXPECTED IN THIS AREA THROUGH MIDNIGHT. * SIGNIFICANT WEATHER: NONE * SPOTTER ACTIVATION: SPOTTER ACTIVATION IS NOT ANTICIPATED. KOSCIELSKI
The office that day
Everything else NWS Sioux Falls, SD issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Sep 8, 11:37 AM CDT | Severe Thunderstorm Warning | FSD | Beadle, Jerauld | 33 min |
| Sep 8, 12:08 PM CDT | Severe Thunderstorm Warning | FSD | Beadle, Sanborn | 32 min |
| Sep 8, 12:28 PM CDT | Severe Thunderstorm Warning | FSD | Brookings, Kingsbury | 27 min |
| Sep 8, 12:58 PM CDT | Severe Thunderstorm Warning | FSD | Brookings, Kingsbury | 32 min |
| Sep 8, 1:24 PM CDT | Severe Thunderstorm Warning | FSD | Lake, Moody | 31 min |
| Sep 8, 1:55 PM CDT | Severe Thunderstorm Warning | FSD | Moody | 30 min |
| Sep 8, 2:10 PM CDT | Severe Thunderstorm Warning | FSD | Minnehaha | 30 min |
| Sep 8, 2:22 PM CDT | Severe Thunderstorm Warning | FSD | Turner | 33 min |
| Sep 8, 2:25 PM CDT | Tornado Warning | FSD | Hutchinson, Turner | 35 min |
| Sep 8, 3:13 PM CDT | Severe Thunderstorm Warning | FSD | Clay, Yankton | 32 min |
| Sep 8, 3:42 PM CDT | Severe Thunderstorm Warning | FSD | Gregory | 33 min |
Nearby
Severe Thunderstorm Warnings in Iowa, 1997Severe Thunderstorm Warnings in South Dakota, 1997Every severe thunderstorm warning in 1997
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; verification from NCEI's Storm Data; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.