The before-and-after images in the map above show the changed landscape left behind by one of the largest and most destructive wildfires on record in California.
The Thomas fire started Dec. 4 in Ventura County. Fanned by strong wind gusts, the fire burned homes and other buildings as it marched north into Santa Barbara County. As of Dec. 18, it was the third-largest fire on record in California.
Use the slider tool feature in the maps above to reveal the fire's impact on neighborhoods.
The fire comes at the end of a devastating year for wildfires in California. In October, the Tubbs fire and other blazes burned homes and businesses in the North Bay area.
High fire risk is expected to last into January, adding to fears that months of deadly and destructive wildfire danger will extend into early next year. CAL FIRE reported 6,877 in California from Jan. 1 to Dec. 10. Wildfires in 2017 have scorched more than 505,000 acres, more than double last year’s burned acreage count. During that same period in 2016, the state firefighting agency reported 4,754 fires that burned 244,303 acres.
The state is coming off one of its wettest winters in years in 2016-2017, which left hillsides covered in grass and other vegetation. That grass dried out in summer and turned into tinder, providing fuel for rapidly spreading fires often pushed by strong winds that can carry hot embers for miles and turn small spot fires into infernos.
An increase in the number of dead and dying trees also has exacerbated the wildfire threat, Cal Fire officials said. An estimated 102 million trees have died in California due to the state's five-year dry spell and bark beetle infestation.