Alert archive / Iowa / Tornado Warnings in 1998

Tornado Warning 54, NWS Des Moines, IA

June 29, 1998Davis County, Iowa

NWS Des Moines, IA issued this tornado warning at Jun 29, 1998, 3:10 PM CDT for Davis County, Iowa. It was in force for 35 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Jun 29, 1998, 3:10 PM CDT (20:10 UTC)
Expired
Jun 29, 1998, 3:45 PM CDT
In force
35 min
Issued by
NWS Des Moines, IA
Area
Whole counties

County Davis County, IA

The watch it was issued in

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

IssuedProductOfficeLasted
Jun 29, 1:00 PM CDTTornado WatchSPC4 hr

The nearest sounding before it

Davenport, (KDVN), launched 12:00Z, 8.2 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.

Skew-T log-pSkew-T log-p diagram, Davenport, at 12:00Z on 1998-06-29Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 917 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Davenport, at 12:00Z on 1998-06-29The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 87 square meters per square second.1939587897117136Sfc1 km3 km6 km9 kmRMLM
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
917 J/kg
Mixed-layer CIN
-115 J/kg
Mixed-layer LCL
762 m above ground
0-6 km bulk shear
28 kt
0-1 km storm-relative helicity
87 m²/s²
0-3 km storm-relative helicity
11 m²/s²
Significant tornado parameter
0.1
Supercell composite
1.5

Open this sounding in Storm Lab

The text

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

471 
WFUS1 KDSM 292011 RRA
TORDSM
IAC051-292045-

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

THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A

* TORNADO WARNING FOR...
  DAVIS COUNTY IN SOUTHEASTERN IOWA

* UNTIL 345 PM CDT

* AT 310 PM CDT... THE PUBLIC REPORTED A TORNADO 13 MILES SOUTH
  SOUTHWEST OF OTTUMWA OR 2 MILES NORTH NORTHWEST OF DRAKESVILLE
  MOVING SOUTHEAST AT 50 MPH.

* THIS TORNADO CAN BE EXPECTED NEAR...
   DRAKESVILLE        BY 312 PM CDT
   BELKNAP            BY 313 PM CDT
   BLOOMFIELD         BY 317 PM CDT
   PULASKI            BY 326 PM CDT

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

COGIL

What forecasters said that day

The local office's own words before this tornado warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

In the hours before

Special weather statement, Jun 29, 10:38 AM CDT, 4 hours 32 minutes before
IAZ004>007-015>017-023>028-033>039-044>050-057>062-070>075-081>086-
092>097-292100-

CENTRAL IOWA THUNDERSTORM OUTLOOK
NATIONAL WEATHER SERVICE DES MOINES IA
1038 AM CDT MON JUN 29 1998

HAZARD--SCATTERED TO NUMEROUS THUNDERSTORMS...SOME PRODUCING SEVERE
WEATHER INCLUDING DAMAGING WINDS...LARGE HAIL AND TORNADOES.

AREA OF CONCERN AND TIMING DETAILS--WEST OF A WAVERLY--FORT DODGE--
CRESTON LINE THROUGH 200 PM...THEN SPREADING EAST THROUGHOUT THE REST
OF IOWA DURING THE MID TO LATE AFTERNOON.

METEOROLOGICAL COMMENTS--A FRONTAL BOUNDARY IS BECOMING MORE
ESTABLISHED FROM NEAR DECORAH TO NEAR SIOUX CITY TO A LOW PRESSURE
CENTER IN SOUTHWEST NEBRASKA.  ISOLATED SEVERE THUNDERSTORMS WERE
ALREADY DEVELOPING IN NORTHEAST NEBRASKA...WEST OF SIOUX CITY.
OTHER STORMS WERE EXPANDING OVER NORTH CENTRAL AND NORTHWEST IOWA
WHICH ARE EXPECTED TO INTENSIFY.  PLENTIFUL MOISTURE AND
INSTABILITY IS AVAILABLE FOR STRONG STORM UPDRAFTS.  STORM-
RELATIVE WIND SHEAR IS QUITE FAVORABLE FOR THE DEVELOPMENT AND
MAINTENANCE OF SUPERCELL THUNDERSTORMS WITH ROTATION...THUS THE
ISOLATED TORNADO THREAT.  AS TEMPERATURES HEAT UP OVER CENTRAL
IOWA...INSTABILITY WILL CONTINUE TO INCREASE WITH CAPE VALUES UP TO
5000 JOULES PER KILOGRAM.

PRECAUTIONS--SPOTTER GROUPS WILL LIKELY BE NEEDED THIS AFTERNOON.  A
SEVERE WEATHER WATCH IS BEING CONSIDERED FOR MUCH OF THE AREA OF
CONCERN ALSO IN THE NEXT 1 OR 2 HOURS.  KEEP ABREAST OF FURTHER
UPDATES AND PAY ATTENTION TO NWS SHORT TERM FORECASTS FOR ADDITIONAL
INFORMATION.

KULA
Special weather statement, Jun 29, 1:25 PM CDT, 1 hour 45 minutes before
IAZ004>007-015>017-023>026-033>034-291930-

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
125 PM CDT MON JUN 29 1998

THE FOLLOWING COUNTIES OF TORNADO WATCH NUMBER 699 HAVE BEEN
CLEARED FROM THE WATCH...

EMMET - KOSSUTH - WINNEBAGO - WORTH - PALO ALTO - HANCOCK - CERRO
GORDO - POCAHONTAS - HUMBOLDT - WRIGHT - FRANKLIN - SAC - AND CALHOUN.

THE REMAINDER OF THE WATCH REMAINS IN EFFECT UNTIL 500 PM.  IN ADDITION
TORNADO WATCH NUMBER 700 REMAINS IN EFFECT UNTIL 500 PM FOR THE REST
OF SOUTHERN AND EASTERN IOWA.

THUNDERSTORMS WILL CONTINUE OVER THE CLEARED COUNTIES...HOWEVER THE
THREAT OF SEVERE WEATHER HAS PASSED TO THE SOUTH.

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 29, 12:18 PM CDTSevere Thunderstorm WarningDMXCarroll47 min
Jun 29, 12:24 PM CDTSevere Thunderstorm WarningDMXCalhoun36 min
Jun 29, 12:32 PM CDTTornado WarningDMXHamilton33 min
Jun 29, 12:37 PM CDTSevere Thunderstorm WarningDMXWebster48 min
Jun 29, 12:41 PM CDTTornado WarningDMXCrawford49 min
Jun 29, 12:59 PM CDTSevere Thunderstorm WarningDMXHardin51 min
Jun 29, 1:09 PM CDTSevere Thunderstorm WarningDMXStory36 min
Jun 29, 1:17 PM CDTSevere Thunderstorm WarningDMXBoone33 min
Jun 29, 1:20 PM CDTSevere Thunderstorm WarningDMXMarshall50 min
Jun 29, 1:23 PM CDTTornado WarningDMXBoone, Dallas32 min
Jun 29, 1:32 PM CDTTornado WarningDMXPolk33 min
Jun 29, 1:39 PM CDTSevere Thunderstorm WarningDMXDallas31 min
Jun 29, 1:44 PM CDTSevere Thunderstorm WarningDMXJasper, Tama46 min
Jun 29, 1:48 PM CDTTornado WarningDMXDallas, Madison47 min
Jun 29, 1:53 PM CDTSevere Thunderstorm WarningDMXWarren32 min
Jun 29, 2:04 PM CDTSevere Thunderstorm WarningDMXPolk21 min
Jun 29, 2:08 PM CDTSevere Thunderstorm WarningDMXPoweshiek47 min
Jun 29, 2:08 PM CDTSevere Thunderstorm WarningDMXMarion47 min
Jun 29, 2:11 PM CDTSevere Thunderstorm WarningDMXMadison34 min
Jun 29, 2:18 PM CDTTornado WarningDMXTama32 min
Jun 29, 2:23 PM CDTTornado WarningDMXMarion32 min
Jun 29, 2:28 PM CDTSevere Thunderstorm WarningDMXLucas, Mahaska, Monroe62 min
Jun 29, 2:28 PM CDTSevere Thunderstorm WarningDMXClarke, Warren62 min
Jun 29, 2:44 PM CDTSevere Thunderstorm WarningDMXWapello66 min
Jun 29, 2:55 PM CDTSevere Thunderstorm WarningDMXAppanoose, Davis65 min
Jun 29, 3:25 PM CDTTornado WarningDMXDallas50 min
Jun 29, 3:27 PM CDTSevere Thunderstorm WarningDMXGuthrie48 min
Jun 29, 3:40 PM CDTTornado WarningDMXPolk35 min
Jun 29, 3:47 PM CDTTornado WarningDMXWarren33 min
Jun 29, 4:05 PM CDTSevere Thunderstorm WarningDMXJasper, Marion50 min
Jun 29, 5:41 PM CDTSevere Thunderstorm WarningDMXClarke49 min
Jun 29, 5:44 PM CDTSevere Thunderstorm WarningDMXTaylor51 min
Jun 29, 6:00 PM CDTSevere Thunderstorm WarningDMXRinggold35 min
Jun 29, 6:19 PM CDTSevere Thunderstorm WarningDMXDecatur66 min
Jun 29, 6:25 PM CDTSevere Thunderstorm WarningDMXAppanoose, Wayne65 min

Nearby

Tornado Warnings in Iowa, 1998Every tornado warning in 1998Tornadoes 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; the sounding from the Mesonet's radiosonde archive.