Alert archive / Iowa / Tornado Warnings in 2004

Tornado Warning 128, NWS Des Moines, IA

October 29, 2004Decatur County, Iowa

NWS Des Moines, IA issued this tornado warning at Oct 29, 2004, 5:10 PM CDT for Decatur County, Iowa. It was in force for 35 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: Oct 29, 2004, 5:10 PM CDT (22:10 UTC)
Expired: Oct 29, 2004, 5:45 PM CDT
In force: 35 min
Issued by: NWS Des Moines, IA
Area: Counties, with a storm outline in the text

County Decatur County, IA

The radar

The Des Moines radar (KDMX), 103 km from the middle of the area, began a volume at 22:11 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
Oct 29, 2:50 PM CDT	Tornado Watch	SPC	6 hr

The nearest sounding before it

Omaha, NE (KOAX), launched 12:00Z, 10.2 hours before the alert went out and 215 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: 1500 J/kg
Mixed-layer CIN: -51 J/kg
Mixed-layer LCL: 695 m above ground
0-6 km bulk shear: 35 kt
0-1 km storm-relative helicity: 227 m²/s²
0-3 km storm-relative helicity: 222 m²/s²
Significant tornado parameter: 1.2
Supercell composite: 7.8

Open this sounding in Storm Lab

The text

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

000 
WFUS53 KDMX 292210
TORDMX
IAC053-292245-
/X.NEW.KDMX.TO.W.0018.041029T2210Z-041029T2245Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
510 PM CDT FRI OCT 29 2004

THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A

* TORNADO WARNING FOR...
  NORTHERN DECATUR COUNTY IN SOUTH CENTRAL IOWA.

* UNTIL 545 PM CDT.

* AT 507 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO. THIS DANGEROUS
  STORM WAS LOCATED 8 MILES WEST OF LEON...OR 57 MILES SOUTH OF DES
  MOINES...AND MOVING NORTHEAST AT 50 MPH.

* THIS STORM WILL BE...
  NEAR VAN WERT BY 515 PM CDT.
  NEAR WELDON BY 520 PM CDT.

THE LOCATIONS OF GRAND RIVER AND DECATUR CITY ARE ALSO IN THE PATH.

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 4079 9405 4068 9386 4090 9356 4090 9396

$$

JAW

The office that day

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

Issued	Product	Office	Counties	Lasted
Oct 29, 5:21 PM CDT	Tornado Warning	DMX	Clarke	39 min
Oct 29, 5:40 PM CDT	Severe Thunderstorm Warning	DMX	Lucas, Warren	35 min
Oct 29, 5:43 PM CDT	Severe Thunderstorm Warning	DMX	Story	17 min
Oct 29, 5:57 PM CDT	Severe Thunderstorm Warning	DMX	Marion	33 min
Oct 29, 5:59 PM CDT	Severe Thunderstorm Warning	DMX	Hardin	16 min
Oct 29, 6:27 PM CDT	Severe Thunderstorm Warning	DMX	Jasper, Poweshiek	33 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.