Hawaii – Rivers of lava streamed from several vents inside the Halemaʻumaʻu crater overnight Monday, highlighting escalating activity at Kilauea as another eruption is expected.

The United States Geological Survey said intermittent lava flows and dome fountaining continued throughout the weekend, signaling persistent volcanic unrest.

The USGS explained that dome fountains are small bubbles of lava. These features are commonly seen before much larger lava fountains, which can shoot molten lava hundreds of feet into the air.

According to the agency, Kilauea has been erupting episodically since Dec. 23, 2024. Each eruptive episode has lasted less than 12 hours, with pauses between eruptions sometimes extending beyond two weeks.

Based on volcanic activity observed over the weekend, the USGS expects the 40th eruptive episode to begin sometime between now and Saturday. In a Sunday update, the agency said the prolonged precursor activity seen over the weekend makes an eruption later in the week more likely.

These eruptions are occurring within a section of Hawaii Volcanoes National Park on the Big Island that has been closed since late 2007.

The USGS also warned that volcanic gas released during eruptions, made up of water vapor, carbon dioxide, and sulfur dioxide, can be hazardous to areas immediately downwind.

Kilauea’s most recent eruptive episode took place on Dec. 24, 2025.

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