Alert archive / Iowa / Tornado Warnings in 2002

Tornado Warning 17, NWS Des Moines, IA

June 20, 2002Webster County, Iowa

NWS Des Moines, IA issued this tornado warning at Jun 20, 2002, 8:30 PM CDT for Webster County, Iowa. It was in force for 45 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 20, 2002, 8:30 PM CDT (01:30 UTC)
Expired
Jun 20, 2002, 9:15 PM CDT
In force
45 min
Issued by
NWS Des Moines, IA
Area
Counties, with a storm outline in the text

County Webster County, IA

The watch it was issued in

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

IssuedProductOfficeLasted
Jun 20, 4:00 PM CDTTornado WatchSPC6 hr

The nearest sounding before it

Omaha, NE (KOAX), launched 00:00Z, 1.5 hours before the alert went out and 218 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 2002-06-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1337 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Omaha, NE at 00:00Z on 2002-06-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 25 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
1337 J/kg
Mixed-layer CIN
-10 J/kg
Mixed-layer LCL
1609 m above ground
0-6 km bulk shear
37 kt
0-1 km storm-relative helicity
25 m²/s²
0-3 km storm-relative helicity
96 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.6

Open this sounding in Storm Lab

The text

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

000 
WFUS53 KDMX 210130
TORDSM
IAC187-210215-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
830 PM CDT THU JUN 20 2002

THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A

* TORNADO WARNING FOR...
  NORTHERN WEBSTER COUNTY IN CENTRAL IOWA
  THIS INCLUDES THE CITY OF FORT DODGE

* UNTIL 915 PM CDT

* AT 828 PM...RADAR INDICATED A THUNDERSTORM THAT HAS PRODUCED A
  TORNADO 7 MILES WEST OF CALLENDER...OR ABOUT 17 MILES SOUTHWEST OF
  FORT DODGE...MOVING NORTHEAST AT 20 MPH.

* THE STORM WILL BE...

  4 MILES NORTHWEST OF CALLENDER AROUND 845 PM...
  NEAR MOORLAND AROUND 850 PM...
  6 MILES SOUTHEAST OF BARNUM AROUND 855 PM...
  6 MILES NORTHWEST OF OTHO AROUND 905 PM...
  NEAR FORT DODGE AROUND 910 PM AND
  6 MILES SOUTH OF BADGER AROUND 915 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.

A TORNADO WATCH REMAINS IN EFFECT UNTIL 1000 PM THURSDAY EVENING FOR
SOUTHWESTERN IOWA.

LAT...LON 4258 9444 4228 9442 4245 9398 4264 9411

JOHNSON

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, 8:32 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, 1:22 PM CDTTornado WarningDMXButler53 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.