In Northern California, authorities have expanded evacuations from the Tamarack Fire in Alpine County in the Sierra Nevada to include the mountain town of Mesa Vista. Started by lightning and fanned by high winds, the fire exploded over the weekend and has burned more than 60 square miles. According to the California Office of Emergency Services, more than 700 people remain evacuated from the fire and more than one thousand firefighters have been assigned to the blaze. The Tamarack Fire was one of many fires burning in a dozen states, most of them in the US West. Extremely dry conditions and heatwaves tied to climate change have made wildfires harder to fight.