Alert archive / Iowa / Tornado Warnings in 2004

Tornado Warning 6, NWS Quad Cities, IA

May 21, 2004Benton County, Iowa

NWS Quad Cities, IA issued this tornado warning at May 21, 2004, 3:38 PM CDT for Benton County, Iowa. It was in force for 37 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
May 21, 2004, 3:38 PM CDT (20:38 UTC)
Expired
May 21, 2004, 4:15 PM CDT
In force
37 min
Issued by
NWS Quad Cities, IA
Area
Counties, with a storm outline in the text

County Benton County, IA

The radar

The Des Moines radar (KDMX), 140 km from the middle of the area, began a volume at 20:37 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 watch it was issued in

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

IssuedProductOfficeLasted
May 21, 10:25 AM CDTSevere Thunderstorm WatchSPC6 hr
May 21, 2:45 PM CDTTornado WatchSPC7 hr

The nearest sounding before it

Minneapolis, MN (KMPX), launched 12:00Z, 8.6 hours before the alert went out and 323 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 2004-05-21Temperature 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°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Minneapolis, MN at 12:00Z on 2004-05-21The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 216 square meters per square second.1939587897Sfc1 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
732 m above ground
0-6 km bulk shear
43 kt
0-1 km storm-relative helicity
216 m²/s²
0-3 km storm-relative helicity
321 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.

753 
WFUS53 KDVN 212038
TORDVN
IAC011-212115-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE QUAD CITIES IA IL
337 PM CDT FRI MAY 21 2004

THE NATIONAL WEATHER SERVICE IN THE QUAD CITIES HAS ISSUED A

* TORNADO WARNING FOR...
  BENTON COUNTY IN EAST CENTRAL IOWA

* UNTIL 415 PM CDT

* AT 333 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM LIKELY TO PRODUCE A TORNADO 8 MILES WEST OF
  GARRISON...OR ABOUT OVER DYSART...MOVING EAST AT 30 MPH.

* THE TORNADO IS EXPECTED TO BE NEAR...
  GARRISON BY 345 PM CDT
  MOUNT AUBURN BY 355 PM CDT
  4 MILES NORTH OF VINTON BY 400 PM CDT
  URBANA BY 410 PM CDT

A SECOND SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO WAS 
ABOUT 5 MILES EAST OF ELBERON.

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 SEVERE THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 400 PM CDT FRIDAY
AFTERNOON FOR NORTHEASTERN IOWA AND NORTHWESTERN ILLINOIS.

LAT...LON 4229 9231 4193 9229 4194 9187 4230 9187

$$

MCCLURE

The office that day

Everything else NWS Quad Cities, IA issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 20, 7:13 PM CDTSevere Thunderstorm WarningDVNJohnson, Washington62 min
May 20, 7:41 PM CDTSevere Thunderstorm WarningDVNLouisa64 min
May 20, 7:54 PM CDTSevere Thunderstorm WarningDVNCedar66 min
May 21, 6:28 AM CDTSevere Thunderstorm WarningDVNBuchanan, Delaware62 min
May 21, 3:26 PM CDTTornado WarningDVNBuchanan64 min
May 21, 3:27 PM CDTSevere Thunderstorm WarningDVNBenton48 min
May 21, 4:12 PM CDTTornado WarningDVNLinn63 min
May 21, 4:14 PM CDTTornado WarningDVNBenton31 min
May 21, 4:43 PM CDTFlash Flood WarningDVNBenton, Buchanan, Delaware, Linn6 hr
May 21, 4:44 PM CDTSevere Thunderstorm WarningDVNBenton61 min
May 21, 4:48 PM CDTTornado WarningDVNBenton57 min
May 21, 4:51 PM CDTSevere Thunderstorm WarningDVNDelaware54 min
May 21, 5:05 PM CDTTornado WarningDVNJones55 min
May 21, 5:21 PM CDTSevere Thunderstorm WarningDVNLinn54 min
May 21, 5:38 PM CDTTornado WarningDVNClinton, Jackson67 min
May 21, 5:51 PM CDTFlash Flood WarningDVNJones6 hr
May 21, 5:56 PM CDTSevere Thunderstorm WarningDVNCedar, Jones64 min

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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.