Thunderstorm Wind in Coos County, New Hampshire

Gusty winds from a severe thunderstorm toppled and snapped trees along the Connecticut River and caused a circus tent to collapse at the Lancaster Fairgrounds. About 100 people were under the tent at the time it collapsed. A 41-year-old man and his 6-year-old daughter were killed in the incident. Another 32 people were reported to have been treated at nearby hospitals. Winds were estimated to have gusted up to 75 mph in the hardest hit area along the Connecticut River where most of the tree damage occurred. No structural damage occurred to any of the permanent buildings at the fairgrounds.

A pre-frontal trough ahead of an approaching cold front was the focus for severe convection on the afternoon of August 3rd. Moderate CAPES and low-level moisture combined with increasing mid-level flow to produced numerous severe cells most of which produced wind damage.