Additional water tankers and scores of firefighters arrived at the Los Angeles area on Monday ahead of fierce winds that were forecast to return and threaten the progress made so far on two massive infernos that have destroyed thousands of homes and killed at least 24 people.

Weary and anxious from a week of massive blazes burning around Los Angeles, Southern California residents faced dire new wildfire warnings and power shutoffs Tuesday while they prepared to flee at a moment’s notice as fire-fueling winds blasted across the scarred landscape.