 While passing near the British Isles on September 6 as an extratropical storm , Danielle produced severe sea conditions on the western part of the isles . Major beach erosion was observed , and many people required rescuing . Coastal portions of Cornwall were evacuated as high waves inundated many homes , and an all @-@ terrain police vehicle was shoved into the sea by a rogue wave in the Isles of Scilly . An 11 ‑ year @-@ old boy and his father were trapped in a sea cave on the north coast of Cornwall due to rough surf . Two other men from Port Isaac also became isolated in the same location after their boat capsized . All four were eventually rescued by a helicopter that hovered near the entrance of the sea cave . At the West Sands Caravan Park near Selsey , West Sussex , twelve families were evacuated to higher ground . A yacht filled with eight people ran aground near Calshot ; they required rescuing by the Solent Coastguards . Flash flooding was reported throughout Wiltshire , especially in the city of Melksham . Numerous motorists were left stranded in inundated streets , while water entered several homes , store basements , a fire station , and the Cooper Avon Tyre Factory . 
