Alert archive / Iowa / Tornado Warnings in 1998

Tornado Warning 56, NWS Des Moines, IA

June 29, 1998Polk County, Iowa

NWS Des Moines, IA issued this tornado warning at Jun 29, 1998, 3:40 PM CDT for Polk County, Iowa. It was in force for 35 min. 5 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: Jun 29, 1998, 3:40 PM CDT (20:40 UTC)
Expired: Jun 29, 1998, 4:15 PM CDT
In force: 35 min
Issued by: NWS Des Moines, IA
Area: Whole counties

County Polk County, IA

What was reported inside it

Time	Report	Where
Jun 29, 3:43 PM CDT	Hail 1.75	Clive, IA
Jun 29, 3:45 PM CDT	Hail 1	West Des Moines, IA
Jun 29, 3:47 PM CDT	Hail 0.75	Clive, IA
Jun 29, 3:50 PM CDT	Hail 2.5	Des Moines Arpt, IA
Jun 29, 4:00 PM CDT	Hail 1.75	Des Moines Arpt, 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
Jun 29, 1:00 PM CDT	Tornado Watch	SPC	4 hr

The nearest sounding before it

Omaha, NE (KOAX), launched 12:00Z, 8.7 hours before the alert went out and 236 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: 2006 J/kg
Mixed-layer CIN: -188 J/kg
Mixed-layer LCL: 850 m above ground
0-6 km bulk shear: 59 kt
0-1 km storm-relative helicity: 71 m²/s²
0-3 km storm-relative helicity: 154 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.1

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KDSM 292040 RRA
TORDSM
IAC153-292115-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
340 PM CDT MON JUN 29 1998

THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A

* TORNADO WARNING FOR...
  SOUTHERN POLK COUNTY IN CENTRAL IOWA

* UNTIL 415 PM CDT

* AT 339 PM CDT... DOPPLER RADAR INDICATED A DEVELOPING TORNADO 11
  MILES WEST OF DES MOINES OR 5 MILES WEST OF CLIVE MOVING EAST
  SOUTHEAST AT 35 MPH.

* THIS TORNADO CAN BE EXPECTED NEAR...
   CLIVE              BY 347 PM CDT
   WINDSOR HEIGHTS    BY 348 PM CDT
   WEST DES MOINES    BY 349 PM CDT
   DES MOINES         BY 356 PM CDT
   PLEASANT HILL      BY 405 PM CDT

GO TO THE BASEMENT OR A SMALL INTERIOR ROOM ON THE LOWEST FLOOR!

COGIL

The office that day

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

Issued	Product	Office	Counties	Lasted
Jun 29, 12:18 PM CDT	Severe Thunderstorm Warning	DMX	Carroll	47 min
Jun 29, 12:24 PM CDT	Severe Thunderstorm Warning	DMX	Calhoun	36 min
Jun 29, 12:32 PM CDT	Tornado Warning	DMX	Hamilton	33 min
Jun 29, 12:37 PM CDT	Severe Thunderstorm Warning	DMX	Webster	48 min
Jun 29, 12:41 PM CDT	Tornado Warning	DMX	Crawford	49 min
Jun 29, 12:59 PM CDT	Severe Thunderstorm Warning	DMX	Hardin	51 min
Jun 29, 1:09 PM CDT	Severe Thunderstorm Warning	DMX	Story	36 min
Jun 29, 1:17 PM CDT	Severe Thunderstorm Warning	DMX	Boone	33 min
Jun 29, 1:20 PM CDT	Severe Thunderstorm Warning	DMX	Marshall	50 min
Jun 29, 1:23 PM CDT	Tornado Warning	DMX	Boone, Dallas	32 min
Jun 29, 1:32 PM CDT	Tornado Warning	DMX	Polk	33 min
Jun 29, 1:39 PM CDT	Severe Thunderstorm Warning	DMX	Dallas	31 min
Jun 29, 1:44 PM CDT	Severe Thunderstorm Warning	DMX	Jasper, Tama	46 min
Jun 29, 1:48 PM CDT	Tornado Warning	DMX	Dallas, Madison	47 min
Jun 29, 1:53 PM CDT	Severe Thunderstorm Warning	DMX	Warren	32 min
Jun 29, 2:04 PM CDT	Severe Thunderstorm Warning	DMX	Polk	21 min
Jun 29, 2:08 PM CDT	Severe Thunderstorm Warning	DMX	Poweshiek	47 min
Jun 29, 2:08 PM CDT	Severe Thunderstorm Warning	DMX	Marion	47 min
Jun 29, 2:11 PM CDT	Severe Thunderstorm Warning	DMX	Madison	34 min
Jun 29, 2:18 PM CDT	Tornado Warning	DMX	Tama	32 min
Jun 29, 2:23 PM CDT	Tornado Warning	DMX	Marion	32 min
Jun 29, 2:28 PM CDT	Severe Thunderstorm Warning	DMX	Lucas, Mahaska, Monroe	62 min
Jun 29, 2:28 PM CDT	Severe Thunderstorm Warning	DMX	Clarke, Warren	62 min
Jun 29, 2:44 PM CDT	Severe Thunderstorm Warning	DMX	Wapello	66 min
Jun 29, 2:55 PM CDT	Severe Thunderstorm Warning	DMX	Appanoose, Davis	65 min
Jun 29, 3:10 PM CDT	Tornado Warning	DMX	Davis	35 min
Jun 29, 3:25 PM CDT	Tornado Warning	DMX	Dallas	50 min
Jun 29, 3:27 PM CDT	Severe Thunderstorm Warning	DMX	Guthrie	48 min
Jun 29, 3:47 PM CDT	Tornado Warning	DMX	Warren	33 min
Jun 29, 4:05 PM CDT	Severe Thunderstorm Warning	DMX	Jasper, Marion	50 min
Jun 29, 5:41 PM CDT	Severe Thunderstorm Warning	DMX	Clarke	49 min
Jun 29, 5:44 PM CDT	Severe Thunderstorm Warning	DMX	Taylor	51 min
Jun 29, 6:00 PM CDT	Severe Thunderstorm Warning	DMX	Ringgold	35 min
Jun 29, 6:19 PM CDT	Severe Thunderstorm Warning	DMX	Decatur	66 min
Jun 29, 6:25 PM CDT	Severe Thunderstorm Warning	DMX	Appanoose, Wayne	65 min

Nearby

Tornado Warnings in Iowa, 1998 Every tornado warning in 1998 Tornadoes in 1998

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.