Alert archive / Iowa / Tornado Warnings in 2007

Tornado Warning 32, NWS Des Moines, IA

August 6, 2007Cass County, Iowa

NWS Des Moines, IA issued this tornado warning at Aug 6, 2007, 8:57 PM CDT for Cass County, Iowa. It was in force for 33 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: Aug 6, 2007, 8:57 PM CDT (01:57 UTC)
Expired: Aug 6, 2007, 9:30 PM CDT
In force: 33 min
Issued by: NWS Des Moines, IA
Area: Counties, with a storm outline in the text

County Cass County, IA

What was reported inside it

Time	Report	Where	Remark
Aug 6, 8:57 PM CDT	TSTM WND DMG	3 Nne Griswold, IA	SIGNIFICANT SIZED TREE DOWN OVER ROAD AT 560TH AND M56.

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

The nearest sounding before it

Omaha, NE (KOAX), launched 00:00Z, 2.0 hours before the alert went out and 120 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: 2407 J/kg
Mixed-layer CIN: -43 J/kg
Mixed-layer LCL: 1157 m above ground
0-6 km bulk shear: 34 kt
0-1 km storm-relative helicity: 114 m²/s²
0-3 km storm-relative helicity: 362 m²/s²
Significant tornado parameter: 2.8
Supercell composite: 22.6

Open this sounding in Storm Lab

The text

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

000 
WFUS53 KDMX 070158
TORDMX
IAC029-070230-
/O.NEW.KDMX.TO.W.0032.070807T0157Z-070807T0230Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
857 PM CDT MON AUG 6 2007

THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A

* TORNADO WARNING FOR...
  CASS COUNTY IN SOUTHWEST IOWA...

* UNTIL 930 PM CDT

* AT 854 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO 9 MILES EAST OF
  GRISWOLD...OR ABOUT 58 MILES NORTH OF TARKIO...MOVING SOUTHEAST AT
  30 MPH.

* THE TORNADO WILL BE NEAR...
  7 MILES SOUTHWEST OF MASSENA BY 910 PM CDT...

THIS TORNADO WARNING IS AN EXTENSION OF THE PREVIOUS WARNING. A WALL 
ROTATING FUNNEL CLOUD HAS BEEN REPORTED NEAR LYMON. TREES ARE 
REPORTED DOWN 3 MILES NORTH OF GRISWOLD AT 857 PM CDT. 

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 4147 9517 4141 9471 4117 9471 4117 9486
      4116 9487 4117 9490 4116 9491 4117 9516
TIME...MOT...LOC 0157Z 301DEG 26KT 4122 9495

$$

VACHALEK

2 follow-up statements

000 
WWUS53 KDMX 070221
SVSDMX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
919 PM CDT MON AUG 6 2007

IAC029-070230-
/O.CON.KDMX.TO.W.0032.000000T0000Z-070807T0230Z/
CASS IA-
919 PM CDT MON AUG 6 2007

...A TORNADO WARNING REMAINS IN EFFECT UNTIL 930 PM CDT FOR CASS
COUNTY...

AT 915 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR CONTINUED TO
INDICATE A TORNADO.  THIS TORNADO WAS LOCATED 7 MILES SOUTH OF
CUMBERLAND...OR ABOUT 57 MILES NORTHEAST OF TARKIO...MOVING SOUTHEAST
AT 30 MPH.

SEEK SHELTER IN A BASEMENT...OR IN AN INTERIOR ROOM. STAY AWAY FROM
WINDOWS. IF YOU ARE IN A CAR OR OUTSIDE...SEEK SHELTER IN A
REINFORCED BUILDING.

TREES WERE REPORTED DOWN 3 MILES NORTHEAST OF GRISWOLD AT 857 PM CDT.

LAT...LON 4147 9517 4141 9471 4117 9471 4117 9486
      4116 9487 4117 9490 4116 9491 4117 9516
TIME...MOT...LOC 0219Z 302DEG 28KT 4116 9485

$$

VACHALEK

000 
WWUS53 KDMX 070235
SVSDMX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
935 PM CDT MON AUG 6 2007

IAC029-070245-
/O.EXP.KDMX.TO.W.0032.000000T0000Z-070807T0230Z/
CASS IA-
935 PM CDT MON AUG 6 2007

...THE TORNADO WARNING FOR CASS COUNTY EXPIRES AT 930 PM CDT...

AT 932 PM CDT...WEATHER SERVICE DOPPLER RADAR INDICATED THAT THE
THUNDERSTORMS WHICH PROMPTED THE WARNING HAVE WEAKENED...AND NO
LONGER POSE AN IMMEDIATE THREAT TO LIFE OR PROPERTY. THEREFORE...THE
TORNADO WARNING WILL BE ALLOWED TO EXPIRE.

A SEVERE THUNDERSTORM WARNING HAS BEEN ISSUED FOR SOUTHEASTERN CASS 
COUNTY TO REPLACE THE TORNADO WARNING. 

LAT...LON 4147 9517 4141 9471 4117 9471 4117 9486
      4116 9487 4117 9490 4116 9491 4117 9516
TIME...MOT...LOC 0221Z 302DEG 28KT 4115 9483

$$

VACHALEK

The office that day

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

Issued	Product	Office	Counties	Lasted
Aug 6, 7:12 PM CDT	Severe Thunderstorm Warning	DMX	Crawford	33 min
Aug 6, 8:25 PM CDT	Severe Thunderstorm Warning	DMX	Cass	65 min
Aug 6, 8:35 PM CDT	Tornado Warning	DMX	Cass	25 min
Aug 6, 9:08 PM CDT	Flash Flood Warning	DMX	Cass	3 hr
Aug 6, 9:17 PM CDT	Severe Thunderstorm Warning	DMX	Adams	58 min
Aug 6, 9:28 PM CDT	Flash Flood Warning	DMX	Audubon	3 hr
Aug 6, 9:31 PM CDT	Severe Thunderstorm Warning	DMX	Cass	44 min
Aug 6, 9:59 PM CDT	Flash Flood Warning	DMX	Guthrie	3 hr
Aug 6, 10:00 PM CDT	Severe Thunderstorm Warning	DMX	Adair	41 min
Aug 6, 10:36 PM CDT	Severe Thunderstorm Warning	DMX	Hamilton	39 min
Aug 6, 10:47 PM CDT	Severe Thunderstorm Warning	DMX	Audubon, Cass	43 min
Aug 6, 10:53 PM CDT	Flash Flood Warning	DMX	Carroll	3 hr
Aug 6, 11:02 PM CDT	Flash Flood Warning	DMX	Grundy, Hardin	3 hr
Aug 6, 11:22 PM CDT	Severe Thunderstorm Warning	DMX	Hardin	38 min
Aug 6, 11:37 PM CDT	Flash Flood Warning	DMX	Crawford	4 hr
Aug 7, 12:07 AM CDT	Flash Flood Warning	DMX	Cass	3 hr
Aug 7, 12:10 AM CDT	Flash Flood Warning	DMX	Audubon	3 hr
Aug 7, 12:22 AM CDT	Flash Flood Warning	DMX	Black Hawk	3 hr
Aug 7, 12:55 AM CDT	Flash Flood Warning	DMX	Guthrie	3 hr
Aug 7, 5:14 PM CDT	Severe Thunderstorm Warning	DMX	Lucas	61 min
Aug 7, 5:18 PM CDT	Severe Thunderstorm Warning	DMX	Wayne	42 min
Aug 7, 5:52 PM CDT	Severe Thunderstorm Warning	DMX	Appanoose, Monroe	38 min
Aug 7, 5:58 PM CDT	Severe Thunderstorm Warning	DMX	Wayne	47 min
Aug 7, 6:01 PM CDT	Severe Thunderstorm Warning	DMX	Taylor	44 min
Aug 7, 6:20 PM CDT	Severe Thunderstorm Warning	DMX	Decatur	40 min
Aug 7, 6:50 PM CDT	Severe Thunderstorm Warning	DMX	Union	40 min
Aug 7, 6:58 PM CDT	Severe Thunderstorm Warning	DMX	Decatur	47 min

Nearby

Tornado Warnings in Iowa, 2007 Every tornado warning in 2007 Tornadoes in 2007

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.