Alert archive / Iowa / Tornado Warnings in 1997

Tornado Warning 10, NWS Des Moines, IA

August 16, 1997Warren County, Iowa

NWS Des Moines, IA issued this tornado warning at Aug 16, 1997, 7:51 PM CDT for Warren County, Iowa. It was in force for 34 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: Aug 16, 1997, 7:51 PM CDT (00:51 UTC)
Expired: Aug 16, 1997, 8:25 PM CDT
In force: 34 min
Issued by: NWS Des Moines, IA
Area: Whole counties

County Warren County, IA

The radar

The Des Moines radar (KDMX), 46 km from the middle of the area, began a volume at 00:55 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
Aug 16, 7:53 PM CDT	Hail 1.75	Indianola, IA
Aug 16, 8:10 PM CDT	Hail 1.75	Indianola, IA
Aug 16, 8:25 PM CDT	Tornado F0	Indianola, 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Aug 16, 7:15 PM CDT	Severe Thunderstorm Watch	SPC	6 hr

The nearest sounding before it

Omaha, NE (KOAX), launched 00:00Z, 0.9 hours before the alert went out and 235 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.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 1159 J/kg
Mixed-layer CIN: -284 J/kg
Mixed-layer LCL: 1161 m above ground
0-6 km bulk shear: 29 kt
0-1 km storm-relative helicity: 96 m²/s²
0-3 km storm-relative helicity: 245 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 18.2

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
TTAA00 KDSM 170051 RRA
TORDSM
IAC181-170125-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
751 PM CDT SAT AUG 16 1997

* TORNADO WARNING FOR
  WARREN COUNTY - SOUTH CENTRAL IOWA

* UNTIL 825 PM CDT
 
* SOME AREAS AFFECTED
    INDIANOLA
    SANDVILLE
    ACKWORTH

* AT 750 PM CDT RADAR INDICATED A TORNADO 5 SOUTHWEST INDIANOLA OR 20
MILES SOUTH OF DES MOINES MOVING   NORTHEAST AT 15 MPH..

* THE STORM WILL BE NEAR INDIANOLA BY 8 PM CDT.

IF YOU ARE NEAR THIS DANGEROUS STORM...TAKE COVER IMMEDIATELY IN THE
LOWEST FLOOR AND INNER MOST ROOM OF A BUILDING.

FORSTER/KUBINA

The office that day

Everything else NWS Des Moines, IA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 16, 8:26 PM CDT	Tornado Warning	DMX	Warren	14 min
Aug 16, 8:34 PM CDT	Severe Thunderstorm Warning	DMX	Monroe	36 min
Aug 16, 8:51 PM CDT	Severe Thunderstorm Warning	DMX	Marion	34 min
Aug 16, 8:58 PM CDT	Severe Thunderstorm Warning	DMX	Polk	32 min

Nearby

Tornado Warnings in Iowa, 1997 Every tornado warning in 1997 Tornadoes 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.