The Dixie Fire grew by about 4500 acres Tuesday and another 6,000 overnight, now at 217,580 acres with 23% containment. Smoke is expected to get very thick in the canyons and valleys. The primary threat to containment is spot fires, with flying embers igniting the very dry fuels on contact. Only trace amounts of rain fell on the fire Tuesday and the increased humidity made it difficult to light backfires for contingency lines. At least 35 structures have been destroyed, as well as 19 other minor structures. Over 10,700 remain threatened. Vast areas are under evacuation orders and warnings in Plumas, Butte, Tehama and Lassen Counties. The Dixie Fire started July 13th, apparently from a PG&E equipment failure.