 During the evening of December 22, the Thomas Fire expanded to , with containment remaining at 65% for the second day, surpassing the Cedar Fire of 2003 to become California's largest wildfire in modern history.By this point, however, fire officials stated that any further growths in the fire's size would likely be due to control burns from firing operations, due to more favorable weather conditions for firefighting.Due to the cooler temperatures and increase in humidity, the control fires were not spreading as intended, so firefighters used flamethrowers to spread the control flames manually.