Alert archive / Iowa / Tornado Watches in 2009

Tornado Watch 347

June 7, 20094 states

The Storm Prediction Center issued this tornado watch at Jun 7, 2009, 10:53 PM CDT for 4 states. It was in force for 5 hr.

The area

The outline as issued.

The facts

Issued
Jun 7, 2009, 10:53 PM CDT (03:53 UTC)
Expired
Jun 8, 2009, 3:56 AM CDT
In force
5 hr
Issued by
the Storm Prediction Center
Largest hail expected
3 in
Strongest gust expected
60 kt
All 55 counties

Adair County, IA, Adams County, IA, Cass County, IA, Clarke County, IA, Dallas County, IA, Decatur County, IA, Fremont County, IA, Jasper County, IA, Lucas County, IA, Madison County, IA, Marion County, IA, Mills County, IA, Montgomery County, IA, Page County, IA, Polk County, IA, Pottawattamie County, IA, Ringgold County, IA, Taylor County, IA, Union County, IA, Warren County, IA, Wayne County, IA, Brown County, KS, Doniphan County, KS, Marshall County, KS, Nemaha County, KS, Washington County, KS, Andrew County, MO, Atchison County, MO, Buchanan County, MO, Caldwell County, MO, Clinton County, MO, Daviess County, MO, DeKalb County, MO, Gentry County, MO, Grundy County, MO, Harrison County, MO, Holt County, MO, Livingston County, MO, Mercer County, MO, Nodaway County, MO, Worth County, MO, Cass County, NE, Douglas County, NE, Gage County, NE, Jefferson County, NE, Johnson County, NE, Lancaster County, NE, Nemaha County, NE, Otoe County, NE, Pawnee County, NE, Richardson County, NE, Saline County, NE, Sarpy County, NE, Saunders County, NE, Seward County, NE

The radar

The Omaha radar (KOAX), 97 km from the middle of the area, began a volume at 03:56 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
30%
Ten or more severe hail reports
60%
One or more hailstones of 2 inches or more
50%
Six or more combined severe hail and wind reports
80%

Warnings issued inside it

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

IssuedProductOfficeCountiesLasted
Jun 7, 10:55 PM CDTTornado WarningEAXDaviess35 min
Jun 7, 11:05 PM CDTSevere Thunderstorm WarningEAXDaviess30 min
Jun 7, 11:20 PM CDTSevere Thunderstorm WarningOAXGage, Jefferson, Lancaster, Saline40 min
Jun 7, 11:22 PM CDTFlash Flood WarningDMXAdams, Taylor6 hr
Jun 7, 11:26 PM CDTSevere Thunderstorm WarningEAXGrundy, Livingston34 min
Jun 7, 11:33 PM CDTSevere Thunderstorm WarningOAXCass, Sarpy, Saunders57 min
Jun 7, 11:48 PM CDTSevere Thunderstorm WarningOAXGage, Johnson, Lancaster, Otoe42 min
Jun 7, 11:56 PM CDTSevere Thunderstorm WarningDMXRinggold38 min
Jun 8, 12:02 AM CDTSevere Thunderstorm WarningDMXAdair, Cass43 min
Jun 8, 12:22 AM CDTSevere Thunderstorm WarningOAXFremont25 min
Jun 8, 12:38 AM CDTSevere Thunderstorm WarningDMXDecatur, Ringgold21 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, 3.9 hours before the alert went out and 98 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 00:00Z on 2009-06-08Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1712 joules per kilogram.LCLLFCEL10008507005003002001001 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 00:00Z on 2009-06-08The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 246 square meters per square second.1939587897Sfc1 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
1712 J/kg
Mixed-layer CIN
-173 J/kg
Mixed-layer LCL
750 m above ground
0-6 km bulk shear
46 kt
0-1 km storm-relative helicity
246 m²/s²
0-3 km storm-relative helicity
272 m²/s²
Significant tornado parameter
0.0
Supercell composite
3.6

Open this sounding in Storm Lab

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Jun 7, 8:49 PM CDTMesoscale DiscussionSPCAppanoose, Benton, Buchanan, Cedar, Davis, Henry and 18 more56 min
Jun 7, 10:22 PM CDTMesoscale DiscussionSPCAdair, Adams, Cass, Dallas, Fremont, Madison and 7 more53 min
Jun 7, 11:09 PM CDTSevere Thunderstorm WatchSPCDes Moines, Henry, Jefferson, Lee, Louisa, Van Buren6 hr
Jun 8, 2:30 AM CDTMesoscale DiscussionSPCAdair, Adams, Appanoose, Cass, Clarke, Dallas and 22 more60 min
Jun 8, 3:25 AM CDTMesoscale DiscussionSPCDes Moines, Henry, Jefferson, Lee, Louisa, Van Buren65 min
Jun 7, 7:08 PM CDTMesoscale DiscussionSPCAnderson, Barber, Butler, Chase, Coffey, Greenwood and 7 more67 min
Jun 7, 8:13 PM CDTMesoscale DiscussionSPCGraham, Jewell, Mitchell, Norton, Osborne, Phillips and 3 more62 min
Jun 7, 11:31 PM CDTSevere Thunderstorm WatchSPCAllen, Bourbon, Butler, Chase, Chautauqua, Cherokee and 14 more5 hr
Jun 8, 12:34 AM CDTSevere Thunderstorm WatchSPCJewell, Mitchell, Osborne, Phillips, Rooks, Smith1 min
Jun 8, 3:20 PM CDTMesoscale DiscussionSPCBollinger, Butler, Cape Girardeau, Carter, Christian, Crawford and 26 more85 min
Jun 8, 4:33 PM CDTSevere Thunderstorm WatchSPCBollinger, Butler, Cape Girardeau, Carter, Crawford, Dent and 20 more5 hr

Nearby

Tornado Watches in Iowa, 2009Tornado Watches in Missouri, 2009Tornado Watches in Nebraska, 2009Every tornado watch in 2009

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.