Alert archive / Iowa / Tornado Warnings in 2011

Tornado Warning 54, NWS Des Moines, IA

July 23, 20114 counties in Iowa

NWS Des Moines, IA issued this tornado warning at Jul 23, 2011, 6:34 PM CDT for 4 counties in Iowa. It was in force for 26 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 23, 2011, 6:34 PM CDT (23:34 UTC)
Expired: Jul 23, 2011, 7:00 PM CDT
In force: 26 min
Issued by: NWS Des Moines, IA
Area: Storm-based polygon

Counties Appanoose County, IA, Lucas County, IA, Monroe County, IA, Wayne County, IA

The radar

The Des Moines radar (KDMX), 104 km from the middle of the area, began a volume at 23:35 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
Jul 23, 5:16 PM CDT	Severe Thunderstorm Watch	SPC	4 hr

The nearest sounding before it

Omaha, NE (KOAX), launched 12:00Z, 11.6 hours before the alert went out and 279 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: 1494 J/kg
Mixed-layer CIN: -247 J/kg
Mixed-layer LCL: 1815 m above ground
0-6 km bulk shear: 23 kt
0-1 km storm-relative helicity: 135 m²/s²
0-3 km storm-relative helicity: 65 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

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

971 
WFUS53 KDMX 232334
TORDMX
IAC007-117-135-185-240000-
/O.NEW.KDMX.TO.W.0054.110723T2334Z-110724T0000Z/

BULLETIN - EAS ACTIVATION REQUESTED
TORNADO WARNING
NATIONAL WEATHER SERVICE DES MOINES IA
634 PM CDT SAT JUL 23 2011

THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A

* TORNADO WARNING FOR...
  NORTHWESTERN APPANOOSE COUNTY IN SOUTH CENTRAL IOWA...
  SOUTHEASTERN LUCAS COUNTY IN SOUTH CENTRAL IOWA...
  SOUTHWESTERN MONROE COUNTY IN SOUTH CENTRAL IOWA...
  NORTHEASTERN WAYNE COUNTY IN SOUTH CENTRAL IOWA...

* UNTIL 700 PM CDT

* AT 631 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
  SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO. THIS DANGEROUS
  STORM WAS LOCATED 12 MILES SOUTHEAST OF CHARITON...OR 18 MILES
  NORTHWEST OF CENTERVILLE...AND MOVING EAST AT 15 MPH.

* LOCATIONS IMPACTED INCLUDE...
  MAINLY RURAL AREAS OF EXTREME NORTHEASTERN WAYNE...EXTREME
  SOUTHEASTERN LUCAS...NORTHWESTERN APPANOOSE AND SOUTHWESTERN MONROE
  COUNTIES.

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.

IN ADDITION TO THE TORNADO...THIS STORM IS ALSO EXPECTED TO PRODUCE 
AND 60 MPH DESTRUCTIVE WINDS.

&&

LAT...LON 4096 9298 4084 9301 4088 9325 4098 9321
TIME...MOT...LOC 2334Z 289DEG 13KT 4091 9311

$$

BEERENDS

3 follow-up statements

737 
WWUS53 KDMX 232343
SVSDMX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
643 PM CDT SAT JUL 23 2011

IAC007-117-135-185-240000-
/O.CON.KDMX.TO.W.0054.000000T0000Z-110724T0000Z/
WAYNE IA-MONROE IA-LUCAS IA-APPANOOSE IA-
643 PM CDT SAT JUL 23 2011

...A TORNADO WARNING REMAINS IN EFFECT FOR NORTHWESTERN APPANOOSE...
SOUTHEASTERN LUCAS...SOUTHWESTERN MONROE AND NORTHEASTERN WAYNE
COUNTIES UNTIL 700 PM CDT...

AT 640 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO.  THIS DANGEROUS
STORM WAS LOCATED 14 MILES SOUTHEAST OF CHARITON...OR 16 MILES
NORTHWEST OF CENTERVILLE...MOVING SOUTHEAST AT 15 MPH.

LOCATIONS IMPACTED INCLUDE...
  MAINLY RURAL AREAS OF EXTREME SOUTHWESTERN MONROE AND NORTHWESTERN
  APPANOOSE COUNTIES.

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 4093 9317 4095 9310 4094 9298 4084 9301
      4087 9320
TIME...MOT...LOC 2343Z 303DEG 15KT 4089 9308

$$

BEERENDS

429 
WWUS53 KDMX 232349
SVSDMX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
649 PM CDT SAT JUL 23 2011

IAC117-135-232359-
/O.CAN.KDMX.TO.W.0054.000000T0000Z-110724T0000Z/
MONROE IA-LUCAS IA-
649 PM CDT SAT JUL 23 2011

...THE TORNADO WARNING FOR SOUTHEASTERN LUCAS AND SOUTHWESTERN MONROE
COUNTIES IS CANCELLED...

THE STORM WHICH PROMPTED THE WARNING HAS MOVED OUT OF THE WARNED 
AREA.

LAT...LON 4087 9320 4090 9319 4090 9304 4090 9300
      4090 9299 4084 9301
TIME...MOT...LOC 2349Z 326DEG 15KT 4086 9309

$$

IAC007-185-240000-
/O.CON.KDMX.TO.W.0054.000000T0000Z-110724T0000Z/
WAYNE IA-APPANOOSE IA-
649 PM CDT SAT JUL 23 2011

...A TORNADO WARNING REMAINS IN EFFECT FOR NORTHWESTERN APPANOOSE AND
NORTHEASTERN WAYNE COUNTIES UNTIL 700 PM CDT...

AT 644 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO.  THIS DANGEROUS
STORM WAS LOCATED 13 MILES NORTH OF SEYMOUR...OR 16 MILES NORTHWEST
OF CENTERVILLE...MOVING SOUTHEAST AT 15 MPH.

LOCATIONS IMPACTED INCLUDE...
  MAINLY RURAL AREAS OF NORTHWESTERN APPANOOSE COUNTY.

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 4087 9320 4090 9319 4090 9304 4090 9300
      4090 9299 4084 9301
TIME...MOT...LOC 2349Z 326DEG 15KT 4086 9309

$$

BEERENDS

499 
WWUS53 KDMX 232359
SVSDMX

SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
659 PM CDT SAT JUL 23 2011

IAC007-185-240007-
/O.EXP.KDMX.TO.W.0054.000000T0000Z-110724T0000Z/
WAYNE IA-APPANOOSE IA-
659 PM CDT SAT JUL 23 2011

...THE TORNADO WARNING FOR NORTHWESTERN APPANOOSE AND NORTHEASTERN
WAYNE COUNTIES WILL EXPIRE AT 700 PM CDT...

THE STORM WHICH PROMPTED THE WARNING HAS MOVED OUT OF THE WARNED
AREA.  HOWEVER GUSTY WINDS ARE STILL POSSIBLE WITH THIS THUNDERSTORM.

IN ADDITION...STRONG THUNDERSTORMS MAY REDEVELOP...AND A SEVERE 
THUNDERSTORM WATCH REMAINS IN EFFECT UNTIL 1 AM CDT.

REMEMBER...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT FOR WAYNE 
AND APPANOOSE COUNTIES UNTIL 730 PM CDT.

LAT...LON 4087 9320 4090 9319 4090 9304 4090 9300
      4090 9299 4084 9301
TIME...MOT...LOC 2357Z 326DEG 15KT 4083 9307

$$

BEERENDS

The office that day

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

Issued	Product	Office	Counties	Lasted
Jul 22, 7:29 PM CDT	Severe Thunderstorm Warning	DMX	Black Hawk, Grundy	46 min
Jul 22, 7:54 PM CDT	Severe Thunderstorm Warning	DMX	Grundy, Marshall, Tama	66 min
Jul 22, 8:02 PM CDT	Severe Thunderstorm Warning	DMX	Jasper, Mahaska, Marion	43 min
Jul 22, 8:33 PM CDT	Severe Thunderstorm Warning	DMX	Jasper, Poweshiek	42 min
Jul 22, 8:47 PM CDT	Severe Thunderstorm Warning	DMX	Jasper, Mahaska, Marion	43 min
Jul 22, 9:08 PM CDT	Severe Thunderstorm Warning	DMX	Poweshiek, Tama	50 min
Jul 22, 10:17 PM CDT	Severe Thunderstorm Warning	DMX	Jasper, Mahaska, Poweshiek	43 min
Jul 23, 5:43 PM CDT	Severe Thunderstorm Warning	DMX	Lucas, Monroe	47 min
Jul 23, 6:15 PM CDT	Severe Thunderstorm Warning	DMX	Appanoose, Lucas, Monroe, Wayne	45 min
Jul 23, 6:42 PM CDT	Severe Thunderstorm Warning	DMX	Appanoose, Lucas, Monroe, Wayne	48 min
Jul 23, 6:47 PM CDT	Tornado Warning	DMX	Appanoose, Wayne	17 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.