Alert archive / Iowa / Tornado Warnings in 1997
Tornado Warning 17, NWS Sioux Falls, SD
NWS Sioux Falls, SD issued this tornado warning at Jul 27, 1997, 11:40 AM CDT for Plymouth County, Iowa. It was in force for 35 min. 3 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, 11:40 AM CDT (16:40 UTC)
- Expired
- Jul 27, 1997, 12:15 PM CDT
- In force
- 35 min
- Issued by
- NWS Sioux Falls, SD
- Area
- Whole counties
County Plymouth County, IA
The radar
The Sioux Falls radar (KFSD), 103 km from the middle of the area, began a volume at 16:42 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, 11:55 AM CDT | Thunderstorm Wind 61 | Le Mars, IA | |
| Jul 27, 12:04 PM CDT | Hail 1.75 | Kingsley, IA | |
| Jul 27, 12:20 PM CDT | Thunderstorm Wind 61 | Remsen, 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, 4.7 hours before the alert went out and 158 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.
000 TTAA00 KFSD 271642 RRA TORFSD IAC149-271715- BULLETIN - EAS ACTIVATION REQUESTED TORNADO WARNING NATIONAL WEATHER SERVICE SIOUX FALLS SD 1140 AM CDT SUN JUL 27 1997 * TORNADO WARNING FOR EASTERN PLYMOUTH COUNTY IN NORTHWESTERN IOWA * UNTIL 1215 PM CDT * THE TORNADO IS CURRENTLY EXPECTED TO REMAIN OVER RURAL AREAS. * AT 1138 AM CDT...LOCAL LAW ENFORCEMENT OFFICIALS REPORTED A TORNADO 23 MILES NORTHEAST OF SIOUX CITY OR 5 MILES SOUTH OF LE MARS MOVING EAST AT 25 MPH. DO NOT USE YOUR CAR TO OUTRUN A TORNADO. CARS ARE EASILY TOSSED AROUND BY TORNADIC WINDS. IF YOU ARE CAUGHT IN THE PATH OF A TORNADO...LEAVE THE CAR AND GO TO A STRONG BUILDING. IF NO STRUCTURE IS NEARBY...SEEK SHELTER IN A DITCH OR LOWV SPOT. UMLAND &
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, 11:53 AM CDT | Severe Thunderstorm Warning | FSD | Cherokee | 47 min |
| Jul 27, 12:16 PM CDT | Severe Thunderstorm Warning | FSD | Plymouth | 34 min |
| Jul 27, 12:46 PM CDT | Tornado Warning | FSD | Buena Vista | 29 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.