Alert archive / Iowa / Tornado Warnings in 2011

Tornado Warning 32, NWS Des Moines, IA

May 11, 2011Adams County, Iowa

NWS Des Moines, IA issued this tornado warning at May 11, 2011, 2:22 PM CDT for Adams County, Iowa. It was in force for 23 min. 2 reports 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: May 11, 2011, 2:22 PM CDT (19:22 UTC)
Expired: May 11, 2011, 2:45 PM CDT
In force: 23 min
Issued by: NWS Des Moines, IA
Area: Storm-based polygon

County Adams County, IA

The radar

The Des Moines radar (KDMX), 125 km from the middle of the area, began a volume at 19:24 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.

What was reported inside it

Time	Report	Where	Remark
May 11, 2:54 PM CDT	FUNNEL CLOUD	2 Sw Corning, IA	LAW ENFORCEMENT REPORTED A FUNNEL CLOUD ON THE SW SIDE OF THE TOWN OF BROOKS. THE FUNNEL DROPPED A LITTLE THEN WENT BACK INTO THE CLOUD.
May 11, 2:55 PM CDT	HAIL 2	3 Ene Nodaway, IA

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 12:00Z, 7.4 hours before the alert went out and 136 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: 909 J/kg
Mixed-layer CIN: -95 J/kg
Mixed-layer LCL: 1123 m above ground
0-6 km bulk shear: 24 kt
0-1 km storm-relative helicity: 55 m²/s²
0-3 km storm-relative helicity: 177 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 3.2

Open this sounding in Storm Lab

The text

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

551 
WFUS53 KDMX 111922
TORDMX
IAC003-111945-
/O.NEW.KDMX.TO.W.0032.110511T1922Z-110511T1945Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
222 PM CDT WED MAY 11 2011

THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A

* TORNADO WARNING FOR...
  WESTERN ADAMS COUNTY IN SOUTHWEST IOWA...

* UNTIL 245 PM CDT

* AT 219 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO. THIS DANGEROUS
  STORM WAS LOCATED 7 MILES EAST OF VILLISCA...OR 15 MILES NORTHEAST
  OF CLARINDA...AND MOVING NORTHEAST AT 15 MPH.

* LOCATIONS IMPACTED INCLUDE...
  CORNING AND CARBON.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A DANGEROUS STORM. IMMEDIATELY SEEK SHELTER IN A BASEMENT...
OR IN AN INTERIOR ROOM OF A REINFORCED BUILDING. STAY AWAY FROM
WINDOWS.

IF YOU ARE OUTSIDE...IN A MOBILE HOME...OR IN A VEHICLE...SEEK
SHELTER IN A NEARBY REINFORCED BUILDING. AS A LAST RESORT...FIND THE
LOWEST SPOT AVAILABLE AND COVER YOUR HEAD.

&&

LAT...LON 4090 9489 4091 9490 4113 9482 4109 9463
      4090 9479 4090 9482
TIME...MOT...LOC 1922Z 203DEG 13KT 4091 9485

$$

COGIL

2 follow-up statements

434 
WWUS53 KDMX 111937
SVSDMX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
237 PM CDT WED MAY 11 2011

IAC003-111945-
/O.CON.KDMX.TO.W.0032.000000T0000Z-110511T1945Z/
ADAMS IA-
237 PM CDT WED MAY 11 2011

...A TORNADO WARNING REMAINS IN EFFECT FOR WESTERN ADAMS COUNTY UNTIL
245 PM CDT...

AT 233 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO.  THIS DANGEROUS
STORM WAS LOCATED 6 MILES SOUTHWEST OF CORNING...OR 18 MILES
NORTHEAST OF CLARINDA...MOVING NORTHEAST AT 10 MPH.

LOCATIONS IMPACTED INCLUDE...
  CORNING AND CARBON.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

THIS IS A DANGEROUS STORM. IMMEDIATELY SEEK SHELTER IN A BASEMENT...
OR IN AN INTERIOR ROOM OF A REINFORCED BUILDING. STAY AWAY FROM
WINDOWS.

IF YOU ARE OUTSIDE...IN A MOBILE HOME...OR IN A VEHICLE...SEEK
SHELTER IN A NEARBY REINFORCED BUILDING. AS A LAST RESORT...FIND THE
LOWEST SPOT AVAILABLE AND COVER YOUR HEAD.

&&

LAT...LON 4090 9489 4091 9490 4113 9482 4109 9463
      4090 9479 4090 9482
TIME...MOT...LOC 1937Z 213DEG 11KT 4094 9481

$$

COGIL

056 
WWUS53 KDMX 111946
SVSDMX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
246 PM CDT WED MAY 11 2011

IAC003-111956-
/O.EXP.KDMX.TO.W.0032.000000T0000Z-110511T1945Z/
ADAMS IA-
246 PM CDT WED MAY 11 2011

...THE TORNADO WARNING FOR WESTERN ADAMS COUNTY HAS EXPIRED...

THE TORNADO THREAT HAS DIMINISHED...THEREFORE THE TORNADO WARNING HAS
EXPIRED. HOWEVER...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT 
FOR PORTIONS OF THE AREA UNTIL 300 PM.  

LAT...LON 4090 9489 4091 9490 4113 9482 4109 9463
      4090 9479 4090 9482
TIME...MOT...LOC 1937Z 213DEG 11KT 4094 9481

$$

COGIL

The office that day

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

Issued	Product	Office	Counties	Lasted
May 11, 12:43 PM CDT	Severe Thunderstorm Warning	DMX	Adams, Cass	47 min
May 11, 2:05 PM CDT	Severe Thunderstorm Warning	DMX	Adams, Taylor	55 min
May 11, 2:43 PM CDT	Flash Flood Warning	DMX	Adams, Taylor	6 hr
May 11, 2:51 PM CDT	Severe Thunderstorm Warning	DMX	Adams, Taylor	39 min
May 11, 4:01 PM CDT	Severe Thunderstorm Warning	DMX	Adams, Taylor	44 min
May 11, 4:11 PM CDT	Tornado Warning	DMX	Adams, Taylor	49 min
May 11, 4:42 PM CDT	Flash Flood Warning	DMX	Adams, Taylor	6 hr
May 11, 4:50 PM CDT	Tornado Warning	DMX	Adams, Union	40 min
May 11, 4:57 PM CDT	Severe Thunderstorm Warning	DMX	Adams, Taylor	38 min
May 11, 5:32 PM CDT	Severe Thunderstorm Warning	DMX	Adams, Ringgold, Taylor, Union	43 min
May 11, 5:42 PM CDT	Tornado Warning	DMX	Union	33 min
May 11, 5:44 PM CDT	Severe Thunderstorm Warning	DMX	Clarke, Decatur, Lucas, Madison, Ringgold, Warren	46 min
May 11, 6:03 PM CDT	Flash Flood Warning	DMX	Union	6 hr
May 11, 6:06 PM CDT	Severe Thunderstorm Warning	DMX	Adair, Clarke, Madison, Union	54 min
May 11, 6:37 PM CDT	Severe Thunderstorm Warning	DMX	Dallas, Madison, Polk, Warren	53 min
May 11, 6:42 PM CDT	Severe Thunderstorm Warning	DMX	Clarke, Decatur, Lucas, Warren	48 min
May 11, 6:46 PM CDT	Severe Thunderstorm Warning	DMX	Wayne	44 min

Nearby

Tornado Warnings in Iowa, 2011 Every tornado warning in 2011 Tornadoes in 2011

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; radar from the NEXRAD Level II archive.