Alert archive / Iowa / Tornado Warnings in 2002

Tornado Warning 20, NWS Des Moines, IA

June 21, 2002Butler County, Iowa

NWS Des Moines, IA issued this tornado warning at Jun 21, 2002, 1:22 PM CDT for Butler County, Iowa. It was in force for 53 min. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Jun 21, 2002, 1:22 PM CDT (18:22 UTC)
Expired
Jun 21, 2002, 2:15 PM CDT
In force
53 min
Issued by
NWS Des Moines, IA
Area
Counties, with a storm outline in the text

County Butler County, IA

The radar

The Des Moines radar (KDMX), 143 km from the middle of the area, began a volume at 18:22 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.

The nearest sounding before it

Minneapolis, MN (KMPX), launched 12:00Z, 6.4 hours before the alert went out and 231 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, Minneapolis, MN at 12:00Z on 2002-06-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 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, Minneapolis, MN at 12:00Z on 2002-06-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 56 square meters per square second.193958Sfc1 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
450 m above ground
0-6 km bulk shear
36 kt
0-1 km storm-relative helicity
56 m²/s²
0-3 km storm-relative helicity
214 m²/s²
Significant tornado parameter
0.0
Supercell composite
2.4

Open this sounding in Storm Lab

The text

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

000 
WFUS53 KDMX 211822
TORDSM
IAC023-211915-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
122 PM CDT FRI JUN 21 2002

THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A

* TORNADO WARNING FOR...
  BUTLER COUNTY IN NORTH CENTRAL IOWA

* UNTIL 215 PM CDT

* AT 117 PM...RADAR INDICATED A THUNDERSTORM CAPABLE OF PRODUCING A
  TORNADO 6 MILES NORTH OF AREDALE...OR ABOUT 19 MILES SOUTHEAST OF
  MASON CITY...MOVING SOUTHEAST AT 10 MPH.

* THE STORM WILL BE...

  4 MILES NORTHEAST OF AREDALE AROUND 140 PM AND
  5 MILES NORTH OF BRISTOW AROUND 215 PM.

THIS IS A HAZARDOUS SITUATION. SEEK SHELTER IN A BASEMENT...OR IN AN
INTERIOR ROOM. STAY AWAY FROM WINDOWS. IF YOU ARE OUTSIDE OR IN A
CAR...SEEK SHELTER IN A REINFORCED BUILDING.

LAT...LON 4297 9293 4283 9305 4264 9278 4282 9259

KINNEY

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 20, 7:21 PM CDTSevere Thunderstorm WarningDMXStory54 min
Jun 20, 8:05 PM CDTSevere Thunderstorm WarningDMXCalhoun, Webster55 min
Jun 20, 8:30 PM CDTTornado WarningDMXWebster45 min
Jun 20, 8:32 PM CDTTornado WarningDMXWebster43 min
Jun 20, 9:23 PM CDTSevere Thunderstorm WarningDMXWebster47 min
Jun 20, 9:40 PM CDTSevere Thunderstorm WarningDMXCrawford50 min
Jun 20, 9:54 PM CDTTornado WarningDMXCrawford51 min
Jun 20, 10:53 PM CDTSevere Thunderstorm WarningDMXWebster52 min
Jun 21, 1:07 PM CDTSevere Thunderstorm WarningDMXCerro Gordo38 min
Jun 21, 2:13 PM CDTTornado WarningDMXButler32 min

Nearby

Tornado Warnings in Iowa, 2002Every tornado warning in 2002Tornadoes in 2002

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; radar from the NEXRAD Level II archive.