(BIVN) – The ongoing eruption at the summit of Kīlauea is paused, with the next episode of lava fountaining expected to occur next week. 

The USGS Hawaiian Volcano Observatory reported on Friday that the “preliminary forecast window for episode 47, based on tilt data, suggests that lava fountaining will occur again sometime between Tuesday, May 12 and Sunday, May 17.” 

UPDATE – (9:45 a.m.) – On Saturday morning, the Observatory adjusted the forecast window for the onset of episode 47 lava fountaining to between Monday, May 11, and Thursday, May 14.

“This window may be adjusted based on continuing observations,” the Observatory added. 

The most recent eruptive activity at Kīlauea, episode 46, occurred at the summit on May 5th.

From the USGS HVO update posted on Friday:

Summit Observations:

Consistent glow from the south vent with occasional flames and intermittent glow from the north vent were observed on webcams overnight. Points of incandescence remain in the crater floor lava flow field emplaced during episode 46, though they are diminishing.

Seismic tremor continues during the current pause, with bursts of tremor every 1–10 minutes that are typical after the end of fountaining and are likely associated with gas pistoning cycles in the eruptive vents. Over the past day, the tremor bursts have become longer with more gradual onsets. Earthquake activity at the summit during and after episode 46 has been low, with 1 small earthquake recorded in the past day.

The Uēkahuna tiltmeter (UWD) recorded about 14.0 microradians of deflationary tilt during episode 46. Since the end episode 46, summit inflation has resumed, with the same tiltmeter recording about 6.9 microradians of inflationary tilt as of this morning.

With the eruption now paused, the SO2 emission rate is likely now varying within a typical range of 1,000 to 5,000 tonnes per day.

Rift Zone Observations:

Rates of seismicity and ground deformation remain low in the East Rift Zone and Southwest Rift Zone. SO2 emissions from the East Rift Zone remain below the detection limit.

Analysis:

The rapid return of inflationary tilt and strong glow from both Halemaʻumaʻu eruptive vents indicates that another lava fountaining episode is likely. The preliminary forecast window for episode 47 is based on data from summit tiltmeters and suggests that lava fountaining will occur sometime between Tuesday, May 12 and Sunday, May 17. This window may be adjusted based on changes to the rate of summit inflation as measured by summit tiltmeters.

Kīlauea has been erupting episodically since December 23, 2024, from two vents (north and south) in Halema‘uma‘u. Lava fountaining episodes, which generally last for less than 12 hours, are separated by pauses that can be longer than three weeks.

HVO continues to closely monitor Kīlauea and is in contact with Hawai‘i Volcanoes National Park and the Hawai‘i County Civil Defense Agency about eruptive hazards.