Storm Events Database

Storm Events Database

Event Details

Event Thunderstorm Wind
Magnitude 52 kts.
State IOWA
County/Area GRUNDY
WFO DMX
Begin Date 06/21/2009 18:16:00 CST-6
Begin Range 2
Begin Azimuth N
Begin Location WELLSBURG
Begin Lat/Lon 42.46/-92.92
End Date 06/21/2009 18:18:00 CST-6
End Range 1
End Azimuth N
End Location WELLSBURG
End Lat/Lon 42.44/-92.92
Deaths Direct/Indirect 0/0 (fatality details below, when available...)
Injuries Direct/Indirect 0/0
Property Damage 5.00K
Crop Damage 0.00K
Episode Narrative Low pressure was located over southeast South Dakota during the afternoon of the 21st. A warm front extended southeast out of the low across central, into southeast Iowa. Considerable moisture was in place from moisture transport the previous night with precipitable water values in the 1.5 to 2 inch range. Surface temperatures warmed into the mid 80s to low 90s, with dew point values in the mid 70s to low 80s. CAPE was 2000 to 3000 J/kg, with 150 to 200 J/kg in the 0-3 km layer. The freezing level was quite high at 17,300 feet with CAPE in the -10 to -30 C layer of the atmosphere of 300 to 500 J/kg. The LCL was quite low at 750 meters with downdraft CAPE of 700 to 1000 J/kg. Thunderstorms erupted over north central Iowa by mid afternoon. The storms were discrete cells, however organization was poor through the afternoon. A landspout was produced by one of the storms as it passed north of Stanhope in Hamilton County. There was some debris in a field as it touched down briefly. Several of the storms produced wall clouds and funnel clouds. A tornado touched down briefly southeast of Williams in Hamilton County. A cluster of storms continued to move east and northeast with numerous reports of land spouts and small tornadoes. The bulk of the reports came from two to three cells traveling together. Though the vast majority of the reports were landspout type tornadoes, there were 2 tornadoes that were on the ground for a few miles. The first was in Grundy County in the Wellsburg and Holland areas. The tornado was on the ground for over 2 miles intermittently. It did have a debris cloud, then became rain wrapped. Another was on the ground for about 2 miles in Grundy County in the Dike area. A hog confinement building was severely damaged west of Dike shortly after the tornado's initial touchdown. The storms began to produce high winds as they exited the CWA. Sixty MPH winds caused tree damage in parts of Grundy County before the storm moved east.
Event Narrative Tree damage with 4 to 6 inch diameter branches snapped.


All events for this episode:

Location County/Zone St. Date Time T.Z. Type Mag Dth Inj PrD CrD
Totals: 0 0 46.00K 16.00K
KAMRAR HAMILTON CO. IA 06/21/2009 15:48 CST-6 Funnel Cloud 0 0 0.00K 0.00K
KAMRAR HAMILTON CO. IA 06/21/2009 15:48 CST-6 Tornado EF0 0 0 0.00K 4.00K
JEWELL HAMILTON CO. IA 06/21/2009 16:32 CST-6 Funnel Cloud 0 0 0.00K 0.00K
WILLIAMS HAMILTON CO. IA 06/21/2009 16:36 CST-6 Tornado EF0 0 0 0.00K 0.00K
WILLIAMS HAMILTON CO. IA 06/21/2009 16:41 CST-6 Funnel Cloud 0 0 0.00K 0.00K
WILLIAMS HAMILTON CO. IA 06/21/2009 16:44 CST-6 Funnel Cloud 0 0 0.00K 0.00K
IOWA FALLS MUNI ARPT HARDIN CO. IA 06/21/2009 16:50 CST-6 Heavy Rain 0 0 0.00K 0.00K
EAGLE CITY HARDIN CO. IA 06/21/2009 17:15 CST-6 Tornado EF0 0 0 0.00K 1.00K
ABBOTT HARDIN CO. IA 06/21/2009 17:39 CST-6 Tornado EF0 0 0 0.00K 1.00K
WELLSBURG GRUNDY CO. IA 06/21/2009 17:51 CST-6 Tornado EF0 0 0 0.00K 1.00K
STEAMBOAT ROCK HARDIN CO. IA 06/21/2009 17:59 CST-6 Tornado EF0 0 0 0.00K 2.00K
WELLSBURG GRUNDY CO. IA 06/21/2009 18:07 CST-6 Funnel Cloud 0 0 0.00K 0.00K
WELLSBURG GRUNDY CO. IA 06/21/2009 18:16 CST-6 Thunderstorm Wind 52 kts. EG 0 0 5.00K 0.00K
DIKE GRUNDY CO. IA 06/21/2009 18:20 CST-6 Tornado EF1 0 0 25.00K 2.00K
WELLSBURG GRUNDY CO. IA 06/21/2009 18:25 CST-6 Tornado EF1 0 0 10.00K 5.00K
HOLLAND GRUNDY CO. IA 06/21/2009 18:30 CST-6 Thunderstorm Wind 52 kts. EG 0 0 3.00K 0.00K
WELLSBURG GRUNDY CO. IA 06/21/2009 18:35 CST-6 Thunderstorm Wind 52 kts. EG 0 0 3.00K 0.00K
CASTLE HILL BLACK HAWK CO. IA 06/21/2009 18:57 CST-6 Funnel Cloud 0 0 0.00K 0.00K
WATERLOO BLACK HAWK CO. IA 06/21/2009 19:17 CST-6 Funnel Cloud 0 0 0.00K 0.00K
Totals: 0 0 46.00K 16.00K