Cooler weather aids firefighters
: Favorable conditions help control one-third of California blaze.
Firefighter advancements
: Increased humidity and cooler temperatures enable progress against fire.
Fire origin
: Blaze started by man pushing burning car into gully.
Fire's extent
: Fire scorches 627 square miles since igniting on July 24.
Terrain challenges
: Rugged landscape complicates efforts to contain the massive fire.
Lassen Volcanic National Park threat
: Fire nears park, causing closure due to danger.
Inaccessible areas
: Difficult terrain hinders use of heavy machinery, prolongs firefighting.
Structure destruction
: Fire destroys 572 structures, damages 52, evacuations continue.
Aircraft deployment
: Clear skies allow helicopter and aircraft assistance in firefighting.
Weather concerns
: Triple-digit temperatures pose ongoing risk for fire spread.
Other Western fires
: 85 large blazes burn across Western United States.
International impact
: Canadian firefighter killed by falling tree while battling blaze.