Thunderstorm Wind — Pottawattamie, Iowa

2008-06-27 · near Lake Manawa, Pottawattamie, Iowa

Event narrative

This is a continuation of a 5 to 7 mile wide damage path that a bow-echo thunderstorm caused across eastern Nebraska and southwest Iowa. In Pottawattamie county Iowa it was estimated by a NWS storm survey that winds reached 70 to 90 mph in an area from Council Bluffs to southwest of Treynor and north of Mineola. There was a concentration of tree damage across this area, which also caused house and vehicle damage. Two adults were killed and one young female adult was injured in Council Bluffs when a tree crushed the parked car they were sitting in. Two Semis were blown off the Interstate near Council Bluffs and grain storage units near Treynor sustained serious damage. In Council Bluffs damage was also noted at the City's Recreation Center, the Public Library, the traffic building and a restaurant and golf course. Damage to trees alone in the northwest part of the city amounted to $275,000. From Council Bluffs the damage swath persisted to areas south and southeast of Macedonia, though wind speeds were estimated to have weakened to 60 to 70 mph. MidAmerican Energy reported that 13,000 customers lost power from the storm in southwest Iowa, including around 11,000 in the Council Bluffs area. According to FEMA and local emergency management damage across the county came to at least $13 million.

Wider weather episode

A bow echo that developed northwest of Omaha produced a 5 to 7 mile wide swath of significant damage surrounded by a larger area of lesser damage from about 40 miles northwest of Omaha to 50 miles to the southeast. Wind speeds in the core of the damage path were measured at 77 mph at the NWS in Valley before the wind equipment failed and a private citizen reportedly measured 98 mph winds on their home weather equipment in far west Omaha. A storm survey done by the NWS estimated that the damage was caused by straight-line winds which reached speeds of 100 to 115 mph in some areas.

The damage swath started in north central Saunders and south central Dodge counties Nebraska and ended in southern Pottawattamie and northern Mills counties Iowa. Numerous trees were snapped or uprooted along the path of the significant damage along with snapped power and street light poles and scattered house and outbuilding damage. Corn and other crops in the path were shredded nearly to the ground.

View location on OpenStreetMap → (41.2400, -95.8600)

Source: NOAA Storm Events Database, event_id 100789. Narrative written by the NWS forecast office that issued the report.