Alert archive / Iowa / Tornado Warnings in 1999

Tornado Warning 39, NWS Des Moines, IA

June 6, 1999Hamilton County, Iowa

NWS Des Moines, IA issued this tornado warning at Jun 6, 1999, 7:08 PM CDT for Hamilton County, Iowa. It was in force for 32 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
Jun 6, 1999, 7:08 PM CDT (00:08 UTC)
Expired
Jun 6, 1999, 7:40 PM CDT
In force
32 min
Issued by
NWS Des Moines, IA
Area
Whole counties

County Hamilton County, IA

The radar

The Des Moines radar (KDMX), 73 km from the middle of the area, began a volume at 00:09 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

TimeReportWhereRemark
Jun 6, 7:15 PM CDTTornado F0Randall, IA
Jun 6, 7:17 PM CDTThunderstorm Wind 61Kamrar, 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.

IssuedProductOfficeLasted
Jun 6, 2:00 PM CDTTornado WatchSPC6 hr
Jun 6, 6:00 PM CDTTornado WatchSPC6 hr

The nearest sounding before it

Omaha, NE (KOAX), launched 00:00Z, 0.1 hours before the alert went out and 250 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, Omaha, NE at 00:00Z on 1999-06-07Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 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, Omaha, NE at 00:00Z on 1999-06-07The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 110 square meters per square second.1939587897117Sfc1 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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
3424 m above ground
0-6 km bulk shear
37 kt
0-1 km storm-relative helicity
110 m²/s²
0-3 km storm-relative helicity
130 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

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

000 
TTAA00 KDSM 070008 RRA
TORDSM
IAC079-070040-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
708 PM CDT SUN JUN 6 1999

THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A

* TORNADO WARNING FOR...
  HAMILTON COUNTY IN CENTRAL IOWA

* UNTIL 740 PM CDT

* AT 707 PM CDT... LOCAL LAW ENFORCEMENT REPORTED A TORNADO 26 MILES
  EAST SOUTHEAST OF FORT DODGE OR 5 MILES SOUTH SOUTHWEST OF
  BLAIRSBURG... MOVING NORTHEAST AT 45 MPH.
6
* THIS TORNADO CAN BE EXPECTED NEAR...
   BLAIRSBURG         BY 712 PM CDT
   WILLIAMS           BY 718 PM CDT

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

JJ/BS

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 6, 7:31 PM CDTSevere Thunderstorm WarningDMXCerro Gordo34 min
Jun 6, 7:49 PM CDTSevere Thunderstorm WarningDMXWorth36 min

Nearby

Tornado Warnings in Iowa, 1999Every tornado warning in 1999Tornadoes in 1999

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.