A week after causing £1.4bn in damage in Houston, the remnants of Tropical Storm Allison flooded homes in southeastern Pennsylvania, blacked out thousands of electrical customers and chased firefighters up trees.

Tornadoes and rain from Tropical Storm Allison have lashed north Florida, causing at least four deaths.

Flooding caused by torrential rain from the remnants of Tropical Storm Allison has forced thousands of people out of their homes in Houston.