Alert archive / Iowa / Tornado Warnings in 2004

Tornado Warning 7, NWS Quad Cities, IA

May 21, 2004Linn County, Iowa

NWS Quad Cities, IA issued this tornado warning at May 21, 2004, 4:12 PM CDT for Linn County, Iowa. It was in force for 63 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, 4:12 PM CDT (21:12 UTC)
Expired: May 21, 2004, 5:15 PM CDT
In force: 63 min
Issued by: NWS Quad Cities, IA
Area: Counties, with a storm outline in the text

County Linn County, IA

The radar

The Quad Cities radar (KDVN), 101 km from the middle of the area, began a volume at 21:14 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.

Issued	Product	Office	Lasted
May 21, 2:45 PM CDT	Tornado Watch	SPC	7 hr

The nearest sounding before it

Lincoln, IL (KILX), launched 12:00Z, 9.2 hours before the alert went out and 332 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-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

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: 2541 J/kg
Mixed-layer CIN: -64 J/kg
Mixed-layer LCL: 923 m above ground
0-6 km bulk shear: 29 kt
0-1 km storm-relative helicity: 59 m²/s²
0-3 km storm-relative helicity: 99 m²/s²
Significant tornado parameter: 0.5
Supercell composite: 3.0

Open this sounding in Storm Lab

The text

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

723 
WFUS53 KDVN 212112
TORDVN
IAC113-212215-

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

THE NATIONAL WEATHER SERVICE IN THE QUAD CITIES HAS ISSUED A

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

* UNTIL 515 PM CDT

* AT 410 PM CDT...TRAINED SPOTTERS REPORTED A TORNADO NEAR 
ATKINS...MOVING EAST AT 20 MPH. THIS STORM HAS A HISTORY OF 
PRODUCING TORNADOES AND VERY LARGE HAIL.

* THE TORNADO IS EXPECTED TO BE NEAR...
  PALO BY 430 PM CDT
  HIAWATHA...CEDAR RAPIDS AND 6 MILES SOUTH OF TODDVILLE BY 445 PM
  CDT
  ROBINS BY 450 PM CDT
  MARION BY 500 PM CDT
  6 MILES NORTH OF BERTRAM BY 505 PM CDT
  SPRINGVILLE...WHITTIER AND 8 MILES SOUTH OF WAUBEEK BY 515 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.

LAT...LON 4213 9167 4220 9145 4207 9142 4195 9155
          4193 9184 4210 9182

$$

ERVIN

The office that day

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

Issued	Product	Office	Counties	Lasted
May 20, 7:13 PM CDT	Severe Thunderstorm Warning	DVN	Johnson, Washington	62 min
May 20, 7:41 PM CDT	Severe Thunderstorm Warning	DVN	Louisa	64 min
May 20, 7:54 PM CDT	Severe Thunderstorm Warning	DVN	Cedar	66 min
May 21, 6:28 AM CDT	Severe Thunderstorm Warning	DVN	Buchanan, Delaware	62 min
May 21, 3:26 PM CDT	Tornado Warning	DVN	Buchanan	64 min
May 21, 3:27 PM CDT	Severe Thunderstorm Warning	DVN	Benton	48 min
May 21, 3:38 PM CDT	Tornado Warning	DVN	Benton	37 min
May 21, 4:14 PM CDT	Tornado Warning	DVN	Benton	31 min
May 21, 4:43 PM CDT	Flash Flood Warning	DVN	Benton, Buchanan, Delaware, Linn	6 hr
May 21, 4:44 PM CDT	Severe Thunderstorm Warning	DVN	Benton	61 min
May 21, 4:48 PM CDT	Tornado Warning	DVN	Benton	57 min
May 21, 4:51 PM CDT	Severe Thunderstorm Warning	DVN	Delaware	54 min
May 21, 5:05 PM CDT	Tornado Warning	DVN	Jones	55 min
May 21, 5:21 PM CDT	Severe Thunderstorm Warning	DVN	Linn	54 min
May 21, 5:38 PM CDT	Tornado Warning	DVN	Clinton, Jackson	67 min
May 21, 5:51 PM CDT	Flash Flood Warning	DVN	Jones	6 hr
May 21, 5:56 PM CDT	Severe Thunderstorm Warning	DVN	Cedar, Jones	64 min

Nearby

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