Alert archive / Iowa / Severe Thunderstorm Warnings in 2002
Severe Thunderstorm Warning 96, NWS Sioux Falls, SD
NWS Sioux Falls, SD issued this severe thunderstorm warning at Jun 11, 2002, 12:45 AM CDT for Clay County, O'Brien County, Iowa. It was in force for 30 min. 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 11, 2002, 12:45 AM CDT (05:45 UTC)
- Expired
- Jun 11, 2002, 1:15 AM CDT
- In force
- 30 min
- Issued by
- NWS Sioux Falls, SD
- Area
- Counties, with a storm outline in the text
Counties Clay County, IA, O'Brien County, IA
The radar
The Sioux Falls radar (KFSD), 115 km from the middle of the area, began a volume at 05:49 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 |
|---|---|---|---|
| Jun 11, 12:51 AM CDT | Thunderstorm Wind 61 E | Hartley, IA | Thunderstorm winds caused widespread tree damage, including whole trees down. |
| Jun 11, 12:55 AM CDT | Thunderstorm Wind 61 E | Primghar, IA | Thunderstorm winds caused widespread tree damage, including at least one tree uprooted. |
| Jun 11, 1:10 AM CDT | Thunderstorm Wind 61 E | Everly, IA | Thunderstorm winds caused widespread tree damage, including several trees blown down. |
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 00:00Z, 5.8 hours before the alert went out and 211 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
- 4189 J/kg
- Mixed-layer CIN
- -6 J/kg
- Mixed-layer LCL
- 1042 m above ground
- 0-6 km bulk shear
- 24 kt
- 0-1 km storm-relative helicity
- 51 m²/s²
- 0-3 km storm-relative helicity
- 204 m²/s²
- Significant tornado parameter
- 2.7
- Supercell composite
- 13.6
The text
As transmitted, in the capitals the NWS used until 2016.
000 WUUS53 KFSD 110545 SVRFSD IAC041-141-110615- BULLETIN - EAS ACTIVATION REQUESTED SEVERE THUNDERSTORM WARNING NATIONAL WEATHER SERVICE SIOUX FALLS SD 1245 AM CDT TUE JUN 11 2002 THE NATIONAL WEATHER SERVICE IN SIOUX FALLS HAS ISSUED A * SEVERE THUNDERSTORM WARNING FOR... CLAY COUNTY IN NORTHWEST IOWA OBRIEN COUNTY IN NORTHWEST IOWA * UNTIL 115 AM CDT * AT 1245 AM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM OVER PRIMGHAR...MOVING EAST AT 35 MPH. * THE SEVERE THUNDERSTORM WILL BE NEAR... HARTLEY AROUND 1255 AM CDT EVERLY AROUND 105 AM CDT ROYAL AROUND 110 AM CDT SPENCER AROUND 115 AM CDT THIS STORM HAS A HISTORY OF PRODUCING DAMAGING WIND. GO INSIDE A STURDY BUILDING AND STAY AWAY FROM WINDOWS. LAT...LON 4320 9572 4302 9575 4293 9511 4316 9507
The office that day
Everything else NWS Sioux Falls, SD issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 11, 1:00 AM CDT | Severe Thunderstorm Warning | FSD | Dickinson | 30 min |
| Jun 11, 1:12 AM CDT | Flash Flood Warning | FSD | Dickinson, Osceola | 2 hr |
| Jun 11, 7:34 AM CDT | Flash Flood Warning | FSD | Woodbury | 116 min |
Nearby
Severe Thunderstorm Warnings in Iowa, 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.