Alert archive / South Dakota / Severe Thunderstorm Warnings in 2002
Severe Thunderstorm Warning 358, NWS Sioux Falls, SD
NWS Sioux Falls, SD issued this severe thunderstorm warning at Aug 21, 2002, 6:54 PM CDT for Gregory County, South Dakota. It was in force for 51 min. 2 reports 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
- Aug 21, 2002, 6:54 PM CDT (23:54 UTC)
- Expired
- Aug 21, 2002, 7:45 PM CDT
- In force
- 51 min
- Issued by
- NWS Sioux Falls, SD
- Area
- Whole counties
County Gregory County, SD
The radar
The North Platte radar (KLNX), 178 km from the middle of the area, began a volume at 23:57 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 |
|---|---|---|---|
| Aug 21, 7:15 PM CDT | Thunderstorm Wind 52 E | Dallas, SD | Thunderstorm winds caused tree damage, including some trees snapped in half. |
| Aug 21, 7:15 PM CDT | Hail 1.75 | Dallas, SD | Large hail covered the ground and a highway. The hail caused widespread and severe crop damage. The amount of crop damage was not known. |
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
Aberdeen, SD (KABR), launched 12:00Z, 11.9 hours before the alert went out and 200 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
- 35 J/kg
- Mixed-layer CIN
- -251 J/kg
- Mixed-layer LCL
- 679 m above ground
- 0-6 km bulk shear
- 22 kt
- 0-1 km storm-relative helicity
- 65 m²/s²
- 0-3 km storm-relative helicity
- 96 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.1
The text
As transmitted, in the capitals the NWS used until 2016.
912 WUUS53 KFSD 212354 SVRFSD SDC053-220045- BULLETIN - EAS ACTIVATION REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE SIOUX FALLS SD 654 PM CDT WED AUG 21 2002 THE NATIONAL WEATHER SERVICE IN SIOUX FALLS HAS ISSUED A * SEVERE THUNDERSTORM WARNING FOR... GREGORY COUNTY IN SOUTH CENTRAL SOUTH DAKOTA * UNTIL 745 PM CDT * AT 654 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM 7 MILES WEST OF DIXON...OR ABOUT 13 MILES EAST OF WINNER...MOVING EAST AT 20 MPH. * THE SEVERE THUNDERSTORM WILL BE NEAR... DIXON AROUND 710 PM CDT THIS STORM HAS A HISTORY OF PRODUCING LARGE HAIL. GO INSIDE A STURDY BUILDING AND STAY AWAY FROM WINDOWS.
The office that day
Everything else NWS Sioux Falls, SD issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 20, 7:17 PM CDT | Severe Thunderstorm Warning | FSD | Davison, Sanborn | 43 min |
| Aug 20, 7:25 PM CDT | Severe Thunderstorm Warning | FSD | Aurora | 35 min |
| Aug 20, 7:48 PM CDT | Severe Thunderstorm Warning | FSD | Gregory | 42 min |
| Aug 20, 8:25 PM CDT | Severe Thunderstorm Warning | FSD | Hanson | 50 min |
| Aug 20, 8:31 PM CDT | Severe Thunderstorm Warning | FSD | Davison | 29 min |
| Aug 20, 8:47 PM CDT | Severe Thunderstorm Warning | FSD | Lake, Miner | 43 min |
| Aug 20, 9:02 PM CDT | Severe Thunderstorm Warning | FSD | McCook | 43 min |
| Aug 20, 9:10 PM CDT | Tornado Warning | FSD | Hanson | 35 min |
| Aug 20, 9:10 PM CDT | Tornado Warning | FSD | Hanson | 35 min |
| Aug 20, 9:17 PM CDT | Severe Thunderstorm Warning | FSD | Aurora | 43 min |
| Aug 20, 9:25 PM CDT | Severe Thunderstorm Warning | FSD | Douglas | 50 min |
| Aug 20, 9:42 PM CDT | Flash Flood Warning | FSD | Aurora, Davison | 108 min |
| Aug 20, 9:42 PM CDT | Severe Thunderstorm Warning | FSD | Minnehaha | 63 min |
| Aug 20, 9:44 PM CDT | Severe Thunderstorm Warning | FSD | McCook | 46 min |
| Aug 20, 10:11 PM CDT | Severe Thunderstorm Warning | FSD | Hutchinson | 49 min |
| Aug 21, 7:46 AM CDT | Flash Flood Warning | FSD | Minnehaha | 119 min |
Nearby
Severe Thunderstorm Warnings in South Dakota, 2002Every severe thunderstorm warning in 2002
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.