Alert archive / Iowa / Tornado Warnings in 1997
Tornado Warning 18, NWS Sioux Falls, SD
NWS Sioux Falls, SD issued this tornado warning at Jul 27, 1997, 12:46 PM CDT for Buena Vista County, Iowa. It was in force for 29 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
- Jul 27, 1997, 12:46 PM CDT (17:46 UTC)
- Expired
- Jul 27, 1997, 1:15 PM CDT
- In force
- 29 min
- Issued by
- NWS Sioux Falls, SD
- Area
- Whole counties
County Buena Vista County, IA
The radar
The Sioux Falls radar (KFSD), 159 km from the middle of the area, began a volume at 17:47 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 |
|---|---|---|---|
| Jul 27, 1:06 PM CDT | Thunderstorm Wind 52 | Storm Lake, IA | Thunderstorm winds caused an unknown amount of tree damage. |
| Jul 27, 1:09 PM CDT | Thunderstorm Wind 52 | Truesdale, 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, 5.8 hours before the alert went out and 187 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
- 1764 J/kg
- Mixed-layer CIN
- -23 J/kg
- Mixed-layer LCL
- 1052 m above ground
- 0-6 km bulk shear
- 8 kt
- 0-1 km storm-relative helicity
- 28 m²/s²
- 0-3 km storm-relative helicity
- 74 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
976 WFUS1 KFSD 271749 RRA TORFSD IAC021-271815- BULLETIN - EAS ACTIVATION REQUESTED TORNADO WARNING NATIONAL WEATHER SERVICE SIOUX FALLS SD 1246 PM CDT SUN JUL 27 1997 * TORNADO WARNING FOR BUENA VISTA COUNTY IN NORTHWESTERN IOWA * UNTIL 115 PM CDT * SOME AREAS AFFECTED STORM LAKE AROUND 100 PM CDT TRUESDALE AROUND 105 PM CDT * AT 1242 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A DEVELOPING TORNADO 50 MILES SOUTH OF SIBLEY OR 11 MILES WEST OF TRUESDALE MOVING EAST AT 30 MPH. THIS STORM HAS A HISTORY OF PRODUCING TORNADOES...SO TAKE SHELTER NOW IF YOU ARE IN THE PATH OF A TORNADO...THE SAFEST PLACE IN A HOME OR BUSINESS IS AN INTERIOR ROOM ON THE LOWEST FLOOR POSSIBLE. AVOID WINDOWS. HEITKAMP
The office that day
Everything else NWS Sioux Falls, SD issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 27, 10:56 AM CDT | Severe Thunderstorm Warning | FSD | Plymouth, Woodbury | 44 min |
| Jul 27, 11:02 AM CDT | Tornado Warning | FSD | Plymouth | 33 min |
| Jul 27, 11:21 AM CDT | Severe Thunderstorm Warning | FSD | Plymouth | 49 min |
| Jul 27, 11:40 AM CDT | Tornado Warning | FSD | Plymouth | 35 min |
| Jul 27, 11:53 AM CDT | Severe Thunderstorm Warning | FSD | Cherokee | 47 min |
| Jul 27, 12:16 PM CDT | Severe Thunderstorm Warning | FSD | Plymouth | 34 min |
Nearby
Tornado Warnings in Iowa, 1997Every tornado warning in 1997Tornadoes 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.