Alert archive / Iowa / Tornado Watches in 2007

Tornado Watch 100

March 31, 20074 states

The Storm Prediction Center issued this tornado watch at Mar 31, 2007, 11:38 AM CDT for 4 states. It was in force for 7 hr.

The area

The outline as issued.

The facts

Issued
Mar 31, 2007, 11:38 AM CDT (16:38 UTC)
Expired
Mar 31, 2007, 7:00 PM CDT
In force
7 hr
Issued by
the Storm Prediction Center
Largest hail expected
2 in
Strongest gust expected
60 kt
All 81 counties

Adair County, IA, Adams County, IA, Appanoose County, IA, Audubon County, IA, Boone County, IA, Buena Vista County, IA, Calhoun County, IA, Carroll County, IA, Cass County, IA, Cherokee County, IA, Clarke County, IA, Clay County, IA, Crawford County, IA, Dallas County, IA, Decatur County, IA, Dickinson County, IA, Emmet County, IA, Fremont County, IA, Greene County, IA, Guthrie County, IA, Hamilton County, IA, Hancock County, IA, Harrison County, IA, Humboldt County, IA, Ida County, IA, Jasper County, IA, Kossuth County, IA, Lucas County, IA, Lyon County, IA, Madison County, IA, Marion County, IA, Mills County, IA, Monona County, IA, Monroe County, IA, Montgomery County, IA, O'Brien County, IA, Osceola County, IA, Page County, IA, Palo Alto County, IA, Plymouth County, IA, Pocahontas County, IA, Polk County, IA, Pottawattamie County, IA, Ringgold County, IA, Sac County, IA, Shelby County, IA, Sioux County, IA, Story County, IA, Taylor County, IA, Union County, IA, Warren County, IA, Wayne County, IA, Webster County, IA, Winnebago County, IA, Woodbury County, IA, Wright County, IA, Atchison County, MO, Gentry County, MO, Grundy County, MO, Harrison County, MO, Holt County, MO, Mercer County, MO, Nodaway County, MO, Putnam County, MO, Sullivan County, MO, Worth County, MO, Burt County, NE, Cass County, NE, Cuming County, NE, Dakota County, NE, Dixon County, NE, Dodge County, NE, Douglas County, NE, Nemaha County, NE, Otoe County, NE, Sarpy County, NE, Saunders County, NE, Thurston County, NE, Washington County, NE, Clay County, SD, Union County, SD

The radar

The Omaha radar (KOAX), 119 km from the middle of the area, began a volume at 16:39 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
60%
One or more EF2 to EF5 tornadoes
20%
Ten or more severe wind reports
30%
One or more gusts of 65 knots or more
30%
Ten or more severe hail reports
60%
One or more hailstones of 2 inches or more
30%
Six or more combined severe hail and wind reports
80%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Mar 31, 11:54 AM CDTTornado WarningOAXJohnson, Otoe36 min
Mar 31, 12:24 PM CDTSevere Thunderstorm WarningEAXGrundy, Livingston, Mercer36 min
Mar 31, 12:55 PM CDTSevere Thunderstorm WarningOAXOtoe37 min
Mar 31, 12:59 PM CDTSevere Thunderstorm WarningOAXSaunders46 min
Mar 31, 1:06 PM CDTSevere Thunderstorm WarningOAXCass39 min
Mar 31, 1:25 PM CDTSevere Thunderstorm WarningOAXSarpy35 min
Mar 31, 1:43 PM CDTSevere Thunderstorm WarningOAXCass17 min
Mar 31, 1:53 PM CDTSevere Thunderstorm WarningOAXSarpy24 min
Mar 31, 1:57 PM CDTSevere Thunderstorm WarningOAXMills30 min
Mar 31, 1:59 PM CDTSevere Thunderstorm WarningDMXLucas, Wayne46 min
Mar 31, 2:00 PM CDTSevere Thunderstorm WarningOAXDouglas45 min
Mar 31, 2:02 PM CDTSevere Thunderstorm WarningOAXDodge28 min
Mar 31, 2:12 PM CDTSevere Thunderstorm WarningOAXWashington39 min
Mar 31, 2:16 PM CDTSevere Thunderstorm WarningOAXPottawattamie44 min
Mar 31, 2:32 PM CDTTornado WarningOAXWashington18 min
Mar 31, 2:34 PM CDTTornado WarningOAXBurt26 min
Mar 31, 2:42 PM CDTSevere Thunderstorm WarningOAXMonona33 min
Mar 31, 2:45 PM CDTSevere Thunderstorm WarningFSDPlymouth, Woodbury30 min
Mar 31, 2:46 PM CDTSevere Thunderstorm WarningDMXJasper, Polk44 min
Mar 31, 2:46 PM CDTTornado WarningDMXGuthrie29 min
Mar 31, 2:48 PM CDTSevere Thunderstorm WarningFSDDakota42 min
Mar 31, 2:55 PM CDTSevere Thunderstorm WarningOAXHarrison25 min
Mar 31, 2:57 PM CDTSevere Thunderstorm WarningOAXThurston48 min
Mar 31, 3:02 PM CDTSevere Thunderstorm WarningDMXJasper43 min
Mar 31, 3:10 PM CDTSevere Thunderstorm WarningDMXBoone, Story35 min
Mar 31, 3:10 PM CDTSevere Thunderstorm WarningOAXThurston35 min
Mar 31, 3:12 PM CDTSevere Thunderstorm WarningOAXMonona33 min
Mar 31, 3:13 PM CDTFlash Flood WarningFSDWoodbury4 hr
Mar 31, 3:18 PM CDTSevere Thunderstorm WarningFSDWoodbury42 min
Mar 31, 3:27 PM CDTFlash Flood WarningFSDPlymouth4 hr
Mar 31, 3:34 PM CDTSevere Thunderstorm WarningDMXAdair, Audubon, Cass, Guthrie41 min
Mar 31, 3:41 PM CDTTornado WarningDMXAudubon, Guthrie34 min
Mar 31, 3:47 PM CDTTornado WarningDMXCalhoun, Webster28 min
Mar 31, 3:51 PM CDTFlash Flood WarningFSDSioux3 hr
Mar 31, 4:06 PM CDTSevere Thunderstorm WarningDMXCarroll, Crawford, Sac39 min
Mar 31, 4:12 PM CDTTornado WarningDMXCarroll33 min
Mar 31, 4:18 PM CDTSevere Thunderstorm WarningDMXCalhoun, Pocahontas, Webster30 min
Mar 31, 4:43 PM CDTTornado WarningDMXCalhoun47 min
Mar 31, 4:47 PM CDTSevere Thunderstorm WarningFSDO'Brien22 min
Mar 31, 4:51 PM CDTSevere Thunderstorm WarningDMXGreene27 min
Mar 31, 4:51 PM CDTSevere Thunderstorm WarningFSDSioux23 min
Mar 31, 5:34 PM CDTTornado WarningDMXPocahontas41 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 12:00Z, 4.6 hours before the alert went out and 119 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-pSkew-T log-p diagram, Omaha, NE at 12:00Z on 2007-03-31Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 0 joules per kilogram.LCL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Omaha, NE at 12:00Z on 2007-03-31The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 252 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
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
0 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
523 m above ground
0-6 km bulk shear
45 kt
0-1 km storm-relative helicity
252 m²/s²
0-3 km storm-relative helicity
288 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Mar 30, 11:44 PM CDTMesoscale DiscussionSPCAdair, Adams, Cass, Clarke, Fremont, Mills and 6 more61 min
Mar 31, 10:30 AM CDTMesoscale DiscussionSPCAdair, Adams, Appanoose, Audubon, Boone, Buena Vista and 46 more90 min
Mar 31, 1:47 PM CDTTornado WatchSPCAllamakee, Benton, Black Hawk, Bremer, Buchanan, Butler and 37 more7 hr
Mar 31, 2:38 PM CDTMesoscale DiscussionSPCAdair, Adams, Audubon, Boone, Calhoun, Carroll and 29 more97 min
Mar 30, 7:12 PM CDTMesoscale DiscussionSPCBarry, Barton, Bates, Cass, Cedar, Dade and 5 more63 min
Mar 31, 12:57 PM CDTMesoscale DiscussionSPCAudrain, Boone, Callaway, Camden, Chariton, Cole and 33 more2 hr
Mar 31, 4:44 PM CDTMesoscale DiscussionSPCMinnehaha, Moody91 min

Nearby

Tornado Watches in Iowa, 2007Tornado Watches in Nebraska, 2007Tornado Watches in Missouri, 2007Every tornado watch 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.