Alert archive / Iowa / Tornado Warnings in 2011
Tornado Warning 43, NWS Des Moines, IA
NWS Des Moines, IA issued this tornado warning at Jun 20, 2011, 11:52 PM CDT for 4 counties in 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
- Jun 20, 2011, 11:52 PM CDT (04:52 UTC)
- Expired
- Jun 21, 2011, 12:15 AM CDT
- In force
- 23 min
- Issued by
- NWS Des Moines, IA
- Area
- Storm-based polygon
Counties Jasper County, IA, Marshall County, IA, Polk County, IA, Story County, IA
The radar
The Des Moines radar (KDMX), 54 km from the middle of the area, began a volume at 04:53 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 |
|---|---|---|---|
| Jun 20, 11:59 PM CDT | TORNADO | 3 Nw Valeria, IA | TORNADO WAS REPORTED ON THE GROUND AT HWY 65 AND NE 112TH ST. |
| Jun 21, 12:08 AM CDT | HAIL 0.75 | Colo, IA |
Local storm reports filed while the alert was in force, from inside its polygon or its counties.
The watch it was issued in
The SPC watch in force over the same counties when this warning went out.
| Issued | Product | Office | Lasted |
|---|---|---|---|
| Jun 20, 6:53 PM CDT | Tornado Watch | SPC | 6 hr |
| Jun 20, 10:58 PM CDT | Tornado Watch | SPC | 4 hr |
The nearest sounding before it
Davenport, (KDVN), launched 00:00Z, 4.9 hours before the alert went out and 227 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.
- Mixed-layer CAPE
- 2585 J/kg
- Mixed-layer CIN
- -110 J/kg
- Mixed-layer LCL
- 699 m above ground
- 0-6 km bulk shear
- 36 kt
- 0-1 km storm-relative helicity
- 184 m²/s²
- 0-3 km storm-relative helicity
- 218 m²/s²
- Significant tornado parameter
- 1.0
- Supercell composite
- 12.8
The text
As transmitted, in the capitals the NWS used until 2016.
773 WFUS53 KDMX 210452 TORDMX IAC099-127-153-169-210515- /O.NEW.KDMX.TO.W.0043.110621T0452Z-110621T0515Z/ BULLETIN - EAS ACTIVATION REQUESTED TORNADO WARNING NATIONAL WEATHER SERVICE DES MOINES IA 1152 PM CDT MON JUN 20 2011 THE NATIONAL WEATHER SERVICE IN DES MOINES HAS ISSUED A * TORNADO WARNING FOR... NORTHWESTERN JASPER COUNTY IN CENTRAL IOWA... MARSHALL COUNTY IN CENTRAL IOWA... NORTHEASTERN POLK COUNTY IN CENTRAL IOWA... SOUTHEASTERN STORY COUNTY IN CENTRAL IOWA... * UNTIL 1215 AM CDT * AT 1148 PM CDT...NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A SEVERE THUNDERSTORM CAPABLE OF PRODUCING A TORNADO. THIS DANGEROUS STORM WAS LOCATED 10 MILES EAST OF HUXLEY...OR 15 MILES SOUTHEAST OF AMES...AND MOVING NORTHEAST AT 50 MPH. * LOCATIONS IMPACTED INCLUDE... MARSHALLTOWN...STATE CENTER...COLLINS...COLO...RHODES... MELBOURNE...ST. ANTHONY...CLEMONS AND ALBION. 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 4221 9312 4203 9282 4173 9334 4188 9355 TIME...MOT...LOC 0452Z 224DEG 45KT 4190 9337 $$ WILKINS
2 follow-up statements
410
WWUS53 KDMX 210507
SVSDMX
SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
1207 AM CDT TUE JUN 21 2011
IAC153-210515-
/O.CAN.KDMX.TO.W.0043.000000T0000Z-110621T0515Z/
POLK IA-
1207 AM CDT TUE JUN 21 2011
...THE TORNADO WARNING FOR NORTHEASTERN POLK COUNTY IS CANCELLED...
THE STORM WHICH PROMPTED THE WARNING HAS MOVED OUT OF POLK COUNTY.
LAT...LON 4178 9326 4183 9335 4186 9335 4186 9340
4192 9349 4221 9312 4203 9282
TIME...MOT...LOC 0505Z 224DEG 45KT 4202 9322
$$
IAC099-127-169-210515-
/O.CON.KDMX.TO.W.0043.000000T0000Z-110621T0515Z/
STORY IA-MARSHALL IA-JASPER IA-
1207 AM CDT TUE JUN 21 2011
...A TORNADO WARNING REMAINS IN EFFECT FOR NORTHWESTERN JASPER...
MARSHALL AND SOUTHEASTERN STORY COUNTIES UNTIL 1215 AM CDT...
AT 1202 AM CDT...TRAINED WEATHER SPOTTERS REPORTED A TORNADO. THIS
TORNADO WAS SPOTTED 3 MILES WEST OF MINGO...AND IS NOW LOCATED 4
MILES NORTH NORTHWEST OF MINGO...MOVING NORTHEAST AT 50 MPH.
LOCATIONS IMPACTED INCLUDE...
MARSHALLTOWN...STATE CENTER...ST. ANTHONY...CLEMONS AND ALBION.
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.
TORNADOES ARE DIFFICULT TO SEE AT NIGHT...ACT QUICKLY. TAKE COVER
NOW.
&&
LAT...LON 4178 9326 4183 9335 4186 9335 4186 9340
4192 9349 4221 9312 4203 9282
TIME...MOT...LOC 0505Z 224DEG 45KT 4202 9322
$$
WILKINS467
WWUS53 KDMX 210516
SVSDMX
SEVERE WEATHER STATEMENT
NATIONAL WEATHER SERVICE DES MOINES IA
1216 AM CDT TUE JUN 21 2011
IAC099-127-169-210526-
/O.EXP.KDMX.TO.W.0043.000000T0000Z-110621T0515Z/
STORY IA-MARSHALL IA-JASPER IA-
1216 AM CDT TUE JUN 21 2011
...THE TORNADO WARNING FOR NORTHWESTERN JASPER...MARSHALL AND
SOUTHEASTERN STORY COUNTIES HAS EXPIRED...
THE STORM WHICH PROMPTED THE WARNING HAS WEAKENED BELOW SEVERE
LIMITS...AND NO LONGER POSES AN IMMEDIATE THREAT TO LIFE OR PROPERTY.
ADDITIONAL STRONG THUNDERSTORMS ARE STILL POSSIBLE WITH MORE
TORNADOES...AND A TORNADO WATCH REMAINS IN EFFECT UNTIL 2 AM CDT
TUESDAY MORNING.
LAT...LON 4178 9326 4183 9335 4186 9335 4186 9340
4192 9349 4221 9312 4203 9282
TIME...MOT...LOC 0507Z 224DEG 45KT 4204 9319
$$
WILKINSThe office that day
Everything else NWS Des Moines, IA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jun 20, 8:32 PM CDT | River Flood Warning | DMX | Mahaska, Marion | 7 hr |
| Jun 20, 8:32 PM CDT | River Flood Warning | DMX | Lucas, Wayne | 11 hr |
| Jun 20, 8:43 PM CDT | Severe Thunderstorm Warning | DMX | Crawford | 47 min |
| Jun 20, 9:30 PM CDT | Severe Thunderstorm Warning | DMX | Adair, Audubon, Cass, Guthrie | 45 min |
| Jun 20, 9:33 PM CDT | Severe Thunderstorm Warning | DMX | Calhoun, Carroll, Crawford, Greene, Sac | 42 min |
| Jun 20, 10:00 PM CDT | Severe Thunderstorm Warning | DMX | Adair, Adams, Cass, Taylor | 30 min |
| Jun 20, 10:16 PM CDT | Severe Thunderstorm Warning | DMX | Adair, Audubon, Boone, Carroll, Cass, Dallas and 3 more | 44 min |
| Jun 20, 10:19 PM CDT | Severe Thunderstorm Warning | DMX | Calhoun, Carroll, Greene, Pocahontas, Sac, Webster | 41 min |
| Jun 20, 10:31 PM CDT | Severe Thunderstorm Warning | DMX | Adair, Adams, Cass, Madison, Taylor, Union | 29 min |
| Jun 20, 10:57 PM CDT | Severe Thunderstorm Warning | DMX | Emmet, Humboldt, Kossuth, Palo Alto, Pocahontas | 48 min |
| Jun 20, 11:26 PM CDT | Severe Thunderstorm Warning | DMX | Boone, Hamilton, Hardin, Marshall, Story | 49 min |
| Jun 20, 11:34 PM CDT | Severe Thunderstorm Warning | DMX | Dallas, Madison, Polk, Warren | 26 min |
| Jun 20, 11:37 PM CDT | Severe Thunderstorm Warning | DMX | Emmet, Hancock, Kossuth, Winnebago | 23 min |
| Jun 20, 11:49 PM CDT | Severe Thunderstorm Warning | DMX | Jasper, Marshall, Polk, Story | 41 min |
| Jun 21, 12:13 AM CDT | Severe Thunderstorm Warning | DMX | Hancock, Winnebago, Worth | 47 min |
| Jun 21, 12:14 AM CDT | Tornado Warning | DMX | Grundy, Hardin | 31 min |
| Jun 21, 12:22 AM CDT | Tornado Warning | DMX | Grundy, Marshall | 23 min |
| Jun 21, 12:35 AM CDT | Tornado Warning | DMX | Jasper, Marshall, Tama | 25 min |
| Jun 21, 12:39 AM CDT | Tornado Warning | DMX | Grundy, Marshall, Tama | 36 min |
| Jun 21, 12:41 AM CDT | Tornado Warning | DMX | Butler | 34 min |
| Jun 21, 1:02 AM CDT | Severe Thunderstorm Warning | DMX | Butler, Franklin | 28 min |
| Jun 21, 1:04 AM CDT | Tornado Warning | DMX | Tama | 27 min |
| Jun 21, 11:15 AM CDT | River Flood Warning | DMX | Palo Alto | 7 days |
| Jun 21, 11:15 AM CDT | River Flood Warning | DMX | Boone, Hamilton, Webster | 11 days |
Nearby
Tornado Warnings in Iowa, 2011Every tornado warning in 2011Tornadoes 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.