North Vent Eruption Breaks Two-Month Pause at Kīlauea Summit
Hawaii’s Kīlauea volcano broke an unusually long two-month pause on Saturday, October 17, 2026, launching its 55th eruptive episode since December 23, 2024. The activity began at 3:19 a.m. local time, sending high lava fountains soaring from the north vent within Halemaʻumaʻu crater.
The previous episode ended on August 25, setting up a dormant stretch that tested the predictability of the monitoring equipment.
Contrasting Fountain Heights and Plume Altitudes
Observations from the Hawaiian Volcano Observatory detailed a dramatic spike in intensity right at the onset of episode 55. The north vent reached a maximum fountain height of 720 feet (220 meters) by 5 a.m., significantly higher than the 500-foot maximums recorded during episodes 51 through 54. By 8 a.m., the fountains had dropped back to around 500 feet (150 meters).
Kilauea Message 2026-10-17 04:21:15 HST. The north vent fountain has grown to about 250 feet (80 m) high and is at least as wide. The fountain is feeding a broad sheet of lava into Halema'uma'u crater. Wind is from the northeast and tephra is within the closed area of HVNP.
The eruption generated a massive plume reaching approximately 25,000 feet above sea level. Winds from the north-northeast pushed volcanic gas and material toward the south-southwest. Radar imaging tracked significant tephra up to 8,000 feet, while National Weather Service data indicated winds above 20,000 feet originating from the west. By mid-morning, the top of the plume cloud had dropped below 13,000 feet.
September Fissure Swarms Complicate Summit Forecasts
The unusually long break was preceded by distinct subsurface shifts. The U.S. Geological Survey documented a series of shallow earthquakes and a magma intrusion in mid-September. Six new fissure vents opened between September 14 and 16, situated 0.1 to 0.6 miles north of the main vent complex and about 150 feet below the base level of the northern vent.
Data from tiltmeters and Global Navigation Satellite System instruments revealed increasing pressure through ground uplift and extension across the summit. Although those September vents generated small lava flows on the crater floor without high fountaining, the deformation and more than 100 earthquakes made it impossible for scientists to predict when a full eruptive episode would return.
Contained Activity and Ongoing Hazards
All lava activity for episode 55 remains strictly contained within the summit crater inside Hawaiʻi Volcanoes National Park. Park officials closed the Halemaʻumaʻu Trail and parts of Byron Ledge Trail earlier in the month due to heightened seismic unrest.
The USGS maintains a Volcano Alert Level of WATCH and an Aviation Color Code of ORANGE for Kīlauea. Sulfur dioxide emissions continue to range between 1,000 and 5,000 tonnes per day, posing ongoing air quality risks downwind. Gas emissions, combined with drifting strands of volcanic glass known as Pele’s hair, threaten sensitive populations and anyone with respiratory vulnerabilities in the area.
The seismic data, summit deformation rates, and gas output metrics that preceded this 55th episode remain central to ongoing research published through the USGS Volcano Watch archives.
