Alert archive / Iowa / Tornado Warnings in 2003

Tornado Warning 26, NWS Des Moines, IA

July 31, 2003Cerro Gordo County, Iowa

NWS Des Moines, IA issued this tornado warning at Jul 31, 2003, 10:51 PM CDT for Cerro Gordo County, Iowa. It was in force for 24 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: Jul 31, 2003, 10:51 PM CDT (03:51 UTC)
Expired: Jul 31, 2003, 11:15 PM CDT
In force: 24 min
Issued by: NWS Des Moines, IA
Area: Counties, with a storm outline in the text

County Cerro Gordo County, IA

The radar

The Des Moines radar (KDMX), 154 km from the middle of the area, began a volume at 03:52 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 nearest sounding before it

Minneapolis, MN (KMPX), launched 00:00Z, 3.9 hours before the alert went out and 200 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: 992 J/kg
Mixed-layer CIN: -7 J/kg
Mixed-layer LCL: 1397 m above ground
0-6 km bulk shear: 37 kt
0-1 km storm-relative helicity: 4 m²/s²
0-3 km storm-relative helicity: 50 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 1.6

Open this sounding in Storm Lab

The text

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

813 
WFUS53 KDMX 010351
TORDMX
IAC033-010415-

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
1051 PM CDT THU JUL 31 2003

THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A

* TORNADO WARNING FOR...
  CERRO GORDO COUNTY IN NORTH CENTRAL IOWA
  THIS INCLUDES THE CITY OF MASON CITY

* UNTIL 1115 PM CDT

* AT 1047 PM...RADAR INDICATED A THUNDERSTORM CAPABLE OF PRODUCING A
  TORNADO OVER ROCKWELL...OR ABOUT 12 MILES SOUTH OF MASON CITY...
  MOVING SOUTHEAST AT 35 MPH.

* THE STORM WILL BE...
  IN RURAL AREAS OF
  SOUTHEASTERN CERRO GORDO COUNTY.

THIS WARNING REPLACES THE SEVERE THUNDERSTORM WARNING PREVIOUSLY
ISSUED FOR THE WARNED AREA.

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 4322 9306 4309 9350 4291 9351 4292 9303

$$

SMALL

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 31, 9:45 PM CDT	Severe Thunderstorm Warning	DMX	Palo Alto	45 min
Jul 31, 10:06 PM CDT	Severe Thunderstorm Warning	DMX	Cerro Gordo	54 min
Jul 31, 10:31 PM CDT	Severe Thunderstorm Warning	DMX	Pocahontas	44 min
Jul 31, 11:04 PM CDT	Tornado Warning	DMX	Butler, Franklin	26 min
Jul 31, 11:44 PM CDT	Severe Thunderstorm Warning	DMX	Butler, Franklin	46 min
Jul 31, 11:58 PM CDT	Severe Thunderstorm Warning	DMX	Wright	32 min
Aug 1, 1:13 PM CDT	Severe Thunderstorm Warning	DMX	Mahaska, Wapello	32 min

Nearby

Tornado Warnings in Iowa, 2003 Every tornado warning in 2003 Tornadoes in 2003

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.