Glacial outburst floods aren't a new phenomenon in Alaska, but climate change is scrambling the geography of risk.

Residents in some parts of Juneau prepared to evacuate ahead of what could be a record surge of flooding as rainwater and snowmelt in a huge basin dammed by Alaska’s Mendenhall Glacier started to flow downstream toward the capital city.

City officials say the flood threat has ended and credit barriers with preventing more damage from the Mendenhall Glacier outburst.