Kīlauea activity intensifies, signaling imminent start of episode 36 of ongoing eruption

Overflows of degassed lava from Kīlauea’s south vent continued through Tuesday night, increasing in both size and duration and signaling that a new eruptive phase may soon begin, according to the U.S. Geological Survey’s Hawaiian Volcano Observatory.

No immediate hazards to nearby communities are expected at this time, the observatory said in a news release.

The current eruption in Halema‘uma‘u Crater within Kilauea’s summit caldera began on Dec. 23, 2024. Since then, 35 episodes of lava fountaining have been separated by short periods without activity. Each episode has unique characteristics.

On Wednesday night, the volcano’s north vent glowed intermittently with all lava overflows since about 3 a.m. on Tuesday having originated from the south vent.

The summit has shown slow inflation over the past 24 hours, suggesting that pressure within the magma system is building. Hawaiian Volcano Observatory scientists said these observations indicate the start of episode 36 is likely approaching, with models forecasting a probable window between Wednesday and Saturday.

During the early morning hours on Tuesday, large overflows from the south vent lasted up to 1 hour and 20 minutes, producing dome-shaped lava fountains between 15 and 30 feet high.

These events significantly expanded the small pāhoehoe flow field surrounding the vent cone. The last three overflows were the largest and longest of 14 recorded since Monday morning.

Instruments at the summit continue to detect steady magma accumulation beneath the summit.

Tremor patterns — a measure of underground volcanic movement — remained consistent for most of the past day, with low tremor periods during lava pond filling followed by brief spikes during drainback. After 3 a.m. Tuesday, tremor patterns shifted to longer, stronger episodes associated with extended overflows.

Gas plumes persisted from both vents on Wednesday morning, with sulfur dioxide emissions remaining at background levels of 1,200 to 1,500 tonnes per day. Favorable winds on Tuesday allowed monitoring arrays southwest of the vent to detect small bursts of gas typically linked to “gas pistoning” events during lava drainback.

The Hawaiian Volcano Observatory continues to closely monitor activity at Kīlauea. For more information:

• Eruption resources, including the most recent map and a timeline of eruption episodes since December 23, 2024: https://www.usgs.gov/volcanoes/kilauea/science/eruption-information

• Three Kīlauea summit livestream videos that show eruptive lava fountains are available here: https://www.youtube.com/@usgs/streams.
  
• Summit eruption webcams: https://www.usgs.gov/volcanoes/kilauea/summit-webcams

• Learn more about gas pistons in a Volcano Watch article here: https://www.usgs.gov/observatories/hvo/news/volcano-watch-so-what-earth-or-least-kilauea-a-gas-piston