| Impact Type | Description | Example | |-------------|-------------|---------| | | Pavement stripped to base course within minutes | 2021 Germany-Ahr Valley (convective burst) | | Boulder transport | Thunder’s seismic vibrations may reduce friction, mobilizing larger clasts | Postulated mechanism; not yet measured directly | | Infrastructure failure | Culverts overwhelmed by both water volume and debris | 2018 Maryland Ellicott City (7” rain in 3 hours) |