Alert archive / Iowa / Tornado Warnings in 2004

Tornado Warning 2, NWS Quad Cities, IA

April 20, 2004Clinton County, Jackson County, Iowa

NWS Quad Cities, IA issued this tornado warning at Apr 20, 2004, 7:05 PM CDT for Clinton County, Jackson County, Iowa. It was in force for 55 min. 1 report came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Apr 20, 2004, 7:05 PM CDT (00:05 UTC)
Expired
Apr 20, 2004, 8:00 PM CDT
In force
55 min
Issued by
NWS Quad Cities, IA
Area
Counties, with a storm outline in the text

Counties Clinton County, IA, Jackson County, IA

What was reported inside it

TimeReportWhereRemark
Apr 20, 7:15 PM CDTTORNADO2 S Delmar, IABUILDINGS DOWN AT 150TH STREET AND HIGHWAY 61.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Davenport, (KDVN), launched 00:00Z, 0.1 hours before the alert went out and 52 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 00:00Z on 2004-04-21Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 601 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 00:00Z on 2004-04-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 246 square meters per square second.19395878Sfc1 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
601 J/kg
Mixed-layer CIN
-5 J/kg
Mixed-layer LCL
756 m above ground
0-6 km bulk shear
36 kt
0-1 km storm-relative helicity
246 m²/s²
0-3 km storm-relative helicity
329 m²/s²
Significant tornado parameter
0.7
Supercell composite
5.8

Open this sounding in Storm Lab

The text

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

000 
WFUS53 KDVN 210005
TORDVN
IAC045-097-210100-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
705 PM CDT TUE APR 20 2004

THE NATIONAL WEATHER SERVICE IN THE QUAD CITIES HAS ISSUED A

* TORNADO WARNING FOR...
  NORTHERN CLINTON COUNTY IN EAST CENTRAL IOWA
  JACKSON COUNTY IN EAST CENTRAL IOWA

* UNTIL 800 PM CDT

* AT 703 PM CDT...THE PUBLIC REPORTED A TORNADO NEAR LOST NATION...OR
  ABOUT 7 MILES SOUTHWEST OF MAQUOKETA...MOVING NORTHEAST AT 20 MPH.

* THE TORNADO IS EXPECTED TO BE NEAR...
  MAQUOKETA...HURSTVILLE AND 5 MILES NORTHWEST OF DELMAR BY 720 PM
  CDT
  5 MILES SOUTHEAST OF FULTON BY 730 PM CDT
  ANDREW BY 740 PM CDT
  SPRINGBROOK BY 750 PM CDT
  BELLEVUE AND 8 MILES NORTHWEST OF GREEN ISLAND BY 800 PM CDT

THE SAFEST PLACE TO BE IN A TORNADO IS IN A BASEMENT OR INTERIOR ROOM
OR HALLWAY ON THE LOWEST FLOOR OF A BUILDING.

A TORNADO WATCH REMAINS IN EFFECT UNTIL 1100 PM CDT TUESDAY EVENING
FOR EAST CENTRAL IOWA AND NORTHWESTERN ILLINOIS.

A SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 1000 PM CDT
TUESDAY EVENING FOR SOUTHEASTERN IOWA AND NORTHEAST MISSOURI.

LAT...LON 4189 9072 4194 9083 4202 9090 4237 9047
          4234 9043 4211 9040

$$

Nearby

Tornado Warnings in Iowa, 2004Every tornado warning in 2004Tornadoes in 2004

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive.