Precursory eruptive activity begins ahead of episode 56 of the ongoing Halemaʻumaʻu eruption at Kīlauea

Precursory low-level activity preceding episode 56 of the ongoing Halemaʻumaʻu eruption began around 11:43 a.m. on Monday, Nov. 2, with a large flow lava from the north vent.

The initial rise of lava to the surface and overflow was passive with no spattering or low dome fountaining, indicating the magma was highly degassed. Minor spatter then began in the vent at about 12:30 p.m., according to the Hawaiian Volcano Observatory.

Drainback accompanied by vigorous spattering began at 12:45 p.m. and ended the initial overflow. Several minutes of vigorous spattering accompanied the rise of lava again within the north vent and preceded the onset of the second overflow at 1 p.m. Once lava reached the surface and began overflowing the vent, spattering became subdued with minor spatter bursts less than 3 feet high on the lava pond surface, according to the HVO.

Accordingly, the Alert Level for Kīlauea was increased from ADVISORY to WATCH and the Aviation Color Code from YELLOW to ORANGE. Alert level and aviation color code definitions: https://www.usgs.gov/programs/VHP/alert-level-system. This low-level precursory activity can continue for hours to days before the lava fountaining episode beings. 

The forecast for episode 56 of lava fountaining to start is between this afternoon to Nov. 7, revised from Nov. 4-7 based on the onset of voluminous precursory overflows. 

Most lava fountaining episodes since Dec. 23, 2024, have continued for a day or less.

Lava flows: generally advance slowly downslope, and during this eruption flows have been confined to Halemaʻumaʻu crater and the southwest side of Kaluapele, Kīlauea’s summit caldera.

“Other significant hazards exist around Kīlauea caldera from Halemaʻumaʻu crater wall instability, ground cracking, and rockfalls that can be enhanced by earthquakes. Close to the vents, the tephra material on the crater rim is prone to cracking, slumping, and small landslides that sometimes expose hot and molten material within,” according to the HVO.

Scientists say this underscores the extremely hazardous nature of Kīlauea’s caldera rim surrounding Halemaʻumaʻu crater, an area that has been closed to the public since late 2007.