The U.S. Geological Survey on Monday issued a Watch alert and an Orange aviation color code for volcanic unrest at Kilauea Volcano.

Precursory low-level eruptive activity began around 11:43 a.m. Hawaii Standard Time on Monday, according to the Hawaiian Volcano Observatory. The agency said this activity occurred before episode 56 of the ongoing Halemaʻumaʻu eruption.

The volcano has a summit elevation of 4,091.21 feet. The agency advised the public to monitor local authorities and media for instructions.