The twister strengthened in Osceola County and produced EF4 damage. At least 2 houses were destroyed, 2 people injured in one of them. 3 vehicles parked under an Iowa Highway 60 overpass were demolished. 11 people in the vehicles were injured.
An estimated F4 tornado made its way from Ankeny, IA (northern Des Moines suburb) and moved southeast ending near Runnels. Two people were killed in their home and there were at least 50 injuries. Approx. 100 homes, a church, a drive-in restaurant and a shopping center was destroyed.
Per the Storm Prediction Center, there were 25 tornadoes on May 16, 1999, nearly half in the state of Iowa. The strongest tornadoes of the day were rated F3. The first formed at 14:45 Local Time in Harrison County, IA. The second formed at 15:16 Local Time also in Harrison County, IA! We will be highlighting both twisters in this summary.
Per the SPC Database, 14 tornadoes occurred on March 13, 1990 in the state of Iowa. The strongest, an F4, traveled 19 miles from Prairieburg in Linn County to Worthington in Dubuque County. It was on the ground for 30 minutes. The max width was 200 yards. There were no injuries or fatalities.