At least 22 people have been killed and dozens are missing after record-breaking rain sent floodwaters surging through central Tennessee as other parts of the US deal with multiple natural disasters including a tropical storm and wildfires.

The flooding in Tennessee’s rural areas began on Saturday and took out roads, cellphone towers and telephone lines, leaving families uncertain about whether their loved ones survived the unprecedented deluge.

Lines of storms moved over the area for hours, wringing out a record amount of moisture - a scenario scientists have warned may be more common because of global warming.