An effusive eruption formed a new lava dome inside the summit crater on 27 December 2020.[6][7] Government officials began to reach out to residents in the area throughout December and January in order to review evacuation plans in case volcanic activity escalated.[3] The effusive eruption continued into January, during which time the lava dome had grown to between 100 and 200 m (330 and 660 ft) wide and 900 m (3,000 ft) long.[9] In February 2021, the lava dome was still actively growing, releasing gas and steam plumes from its top.[10]