Alert archive / Iowa / Tornado Watches in 2008

Tornado Watch 389

May 29, 200835 counties in Iowa; Atchison County, Doniphan County, Kansas; 16 counties in Missouri

The Storm Prediction Center issued this tornado watch at May 29, 2008, 8:13 PM CDT for 35 counties in Iowa; Atchison County, Doniphan County, Kansas; 16 counties in Missouri. It was in force for 8 hr.

The area

The outline as issued.

The facts

Issued: May 29, 2008, 8:13 PM CDT (01:13 UTC)
Expired: May 30, 2008, 4:42 AM CDT
In force: 8 hr
Issued by: the Storm Prediction Center
Largest hail expected: 2 in
Strongest gust expected: 70 kt

All 53 counties

Adair County, IA, Adams County, IA, Appanoose County, IA, Audubon County, IA, Boone County, IA, Calhoun County, IA, Carroll County, IA, Cass County, IA, Clarke County, IA, Crawford County, IA, Dallas County, IA, Decatur County, IA, Greene County, IA, Grundy County, IA, Guthrie County, IA, Hamilton County, IA, Hardin County, IA, Jasper County, IA, Lucas County, IA, Madison County, IA, Mahaska County, IA, Marion County, IA, Marshall County, IA, Monroe County, IA, Polk County, IA, Poweshiek County, IA, Ringgold County, IA, Sac County, IA, Story County, IA, Tama County, IA, Taylor County, IA, Union County, IA, Warren County, IA, Wayne County, IA, Webster County, IA, Atchison County, KS, Doniphan County, KS, Andrew County, MO, Atchison County, MO, Buchanan County, MO, Daviess County, MO, DeKalb County, MO, Gentry County, MO, Grundy County, MO, Harrison County, MO, Holt County, MO, Linn County, MO, Livingston County, MO, Mercer County, MO, Nodaway County, MO, Putnam County, MO, Sullivan County, MO, Worth County, MO

The radar

The Des Moines radar (KDMX), 52 km from the middle of the area, began a volume at 00:56 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 SPC expected

The probabilities SPC published with the watch, for the watch area over its life.

Two or more tornadoes: 40%
One or more EF2 to EF5 tornadoes: 20%
Ten or more severe wind reports: 60%
One or more gusts of 65 knots or more: 50%
Ten or more severe hail reports: 40%
One or more hailstones of 2 inches or more: 30%
Six or more combined severe hail and wind reports: 80%

Warnings issued inside it

34 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

Issued	Product	Office	Counties	Lasted
May 29, 8:16 PM CDT	Severe Thunderstorm Warning	DMX	Sac	44 min
May 29, 8:29 PM CDT	Tornado Warning	DMX	Crawford	31 min
May 29, 8:43 PM CDT	Severe Thunderstorm Warning	DMX	Calhoun, Pocahontas	32 min
May 29, 8:56 PM CDT	Tornado Warning	DMX	Calhoun, Carroll	34 min
May 29, 9:09 PM CDT	Tornado Warning	DMX	Carroll	27 min
May 29, 9:23 PM CDT	Tornado Warning	DMX	Greene	31 min
May 29, 9:24 PM CDT	Severe Thunderstorm Warning	DMX	Calhoun, Greene, Webster	51 min
May 29, 9:30 PM CDT	Tornado Warning	DMX	Webster	30 min
May 29, 10:02 PM CDT	Severe Thunderstorm Warning	DMX	Hamilton, Hardin	43 min
May 29, 10:24 PM CDT	Severe Thunderstorm Warning	DMX	Guthrie	39 min
May 29, 10:34 PM CDT	Flash Flood Warning	DMX	Crawford	6 hr
May 29, 10:55 PM CDT	Tornado Warning	DMX	Dallas	35 min
May 29, 11:07 PM CDT	Severe Thunderstorm Warning	DMX	Carroll, Crawford	53 min
May 29, 11:30 PM CDT	Severe Thunderstorm Warning	DMX	Audubon, Guthrie	45 min
May 29, 11:48 PM CDT	Flash Flood Warning	DMX	Calhoun, Carroll, Greene, Sac	6 hr
May 29, 11:50 PM CDT	Severe Thunderstorm Warning	DMX	Calhoun, Carroll, Greene	40 min
May 29, 11:56 PM CDT	Tornado Warning	DMX	Audubon, Guthrie	34 min
May 30, 12:15 AM CDT	Severe Thunderstorm Warning	EAX	Atchison, Holt	45 min
May 30, 12:19 AM CDT	Severe Thunderstorm Warning	DMX	Adair, Guthrie	29 min
May 30, 12:23 AM CDT	Severe Thunderstorm Warning	DMX	Jasper, Marshall, Story	37 min
May 30, 12:26 AM CDT	Tornado Warning	EAX	Atchison	34 min
May 30, 12:27 AM CDT	Flash Flood Warning	DMX	Boone, Calhoun, Greene, Hamilton, Hardin, Story and 1 more	6 hr
May 30, 12:27 AM CDT	Tornado Warning	DMX	Jasper, Marshall	33 min
May 30, 12:41 AM CDT	Tornado Warning	DMX	Tama	34 min
May 30, 12:46 AM CDT	Tornado Warning	DMX	Dallas	31 min
May 30, 1:04 AM CDT	Severe Thunderstorm Warning	DMX	Adams, Taylor	41 min
May 30, 1:14 AM CDT	Severe Thunderstorm Warning	DMX	Adair, Cass	46 min
May 30, 1:41 AM CDT	Severe Thunderstorm Warning	DMX	Adair, Adams, Clarke, Dallas, Guthrie, Madison and 2 more	49 min
May 30, 1:50 AM CDT	Severe Thunderstorm Warning	DMX	Clarke, Decatur, Ringgold, Union, Warren	40 min
May 30, 1:53 AM CDT	Flash Flood Warning	DMX	Black Hawk, Grundy, Hardin, Marshall, Tama	6 hr
May 30, 2:01 AM CDT	Flash Flood Warning	DMX	Audubon, Dallas, Guthrie	6 hr
May 30, 4:05 AM CDT	Tornado Warning	DMX	Clarke, Union	40 min
May 30, 4:25 AM CDT	Severe Thunderstorm Warning	DMX	Clarke, Lucas, Marion, Warren	50 min
May 30, 4:40 AM CDT	Tornado Warning	DMX	Clarke, Lucas, Warren	19 min

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Omaha, NE (KOAX), launched 00:00Z, 1.2 hours before the alert went out and 179 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: 3876 J/kg
Mixed-layer CIN: -5 J/kg
Mixed-layer LCL: 824 m above ground
0-6 km bulk shear: 45 kt
0-1 km storm-relative helicity: 236 m²/s²
0-3 km storm-relative helicity: 285 m²/s²
Significant tornado parameter: 6.4
Supercell composite: 26.8

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
May 29, 7:37 PM CDT	Mesoscale Discussion	SPC	Adair, Adams, Appanoose, Audubon, Boone, Calhoun and 25 more	53 min
May 29, 10:21 PM CDT	Mesoscale Discussion	SPC	Plymouth, Sioux, Woodbury	24 min
May 29, 11:34 PM CDT	Mesoscale Discussion	SPC	Adair, Adams, Appanoose, Audubon, Black Hawk, Boone and 38 more	56 min
May 30, 1:19 AM CDT	Tornado Watch	SPC	Appanoose, Benton, Cedar, Clarke, Clinton, Davis and 25 more	8 hr
May 30, 1:37 AM CDT	Mesoscale Discussion	SPC	Fremont, Harrison, Mills, Monona, Montgomery, Page and 2 more	53 min
May 30, 2:17 AM CDT	Mesoscale Discussion	SPC	Adair, Adams, Appanoose, Audubon, Benton, Boone and 49 more	88 min
May 30, 6:00 AM CDT	Mesoscale Discussion	SPC	Appanoose, Cedar, Clinton, Davis, Des Moines, Henry and 13 more	2 hr
May 30, 7:56 AM CDT	Tornado Watch	SPC	Des Moines, Henry, Lee, Louisa, Muscatine, Van Buren	6 hr
May 30, 4:29 PM CDT	Mesoscale Discussion	SPC	Davis, Des Moines, Henry, Jefferson, Lee, Louisa and 3 more	61 min
May 30, 4:58 PM CDT	Severe Thunderstorm Watch	SPC	Allamakee, Chickasaw, Clayton, Fayette, Floyd, Howard and 2 more	3 hr
May 29, 9:19 PM CDT	Mesoscale Discussion	SPC	Finney, Grant, Gray, Greeley, Hamilton, Haskell and 12 more	56 min
May 29, 9:38 PM CDT	Mesoscale Discussion	SPC	Cloud, Decatur, Ellis, Ellsworth, Gove, Graham and 14 more	37 min
May 29, 9:46 PM CDT	Severe Thunderstorm Watch	SPC	Ellis, Finney, Gove, Graham, Grant, Greeley and 12 more	5 hr
May 29, 10:02 PM CDT	Tornado Watch	SPC	Cloud, Jewell, Mitchell, Osborne, Phillips, Republic and 2 more	4 hr
May 30, 2:25 AM CDT	Mesoscale Discussion	SPC	Finney, Grant, Gray, Haskell, Hodgeman, Kearny and 4 more	65 min
May 30, 2:23 PM CDT	Mesoscale Discussion	SPC	Allen, Anderson, Bourbon, Butler, Chautauqua, Coffey and 16 more	97 min
May 30, 2:42 PM CDT	Tornado Watch	SPC	Allen, Anderson, Bourbon, Chautauqua, Cherokee, Coffey and 15 more	7 hr
May 30, 1:14 PM CDT	Mesoscale Discussion	SPC	Lincoln, Pike, Saint Charles, Saint Louis, City of Saint Louis	2 hr
May 30, 1:56 PM CDT	Tornado Watch	SPC	Audrain, Boone, Callaway, Cole, Franklin, Gasconade and 16 more	8 hr
May 30, 5:18 PM CDT	Mesoscale Discussion	SPC	Audrain, Boone, Callaway, Carroll, Chariton, Cole and 24 more	87 min

Nearby

Tornado Watches in Iowa, 2008 Tornado Watches in Missouri, 2008 Tornado Watches in Kansas, 2008 Every tornado watch in 2008

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.