Hawaiian Volcano Update: Kīlauea Intrusion Ends, Summit Pressurized - October 8, 2026

Last week’s intrusion into Kīlauea summit lasted from around 2 PM on September 30 until 8 AM on October 2, ending sometime after a magnitude 3.5 earthquake beneath the northern edge of Halemaʻumaʻu accomodated the area to the new magma. Since then, there has been little sign of reactivation of that near-vertical blade of magma that, according to the USGS Hawaiian Volcano Observatory, reached within 1000 feet or 300 meters of the surface after earthquakes announced the start of magma injection into deep cracks formed during the 2018 colapse. 

The overall interpretation is that “the rising elevation of the established north-south-west vents over the course of this eruption has increased the pressure necessary to push magma out of the vents and trigger a major fountain episode.” Further, “the occurrence of these two small-volume intrusions below Kīlauea’s summit region within the past month suggests the pressure required to erupt dense degassed magma from the established vents is also high enough to allow magma to exploit weakenesses below the surface along the pre-existing, 2018 crack systems.” Thus, besides the potential outcomes of a return to fountaining, formation of new summit vents, and intrusion into the upper rift zones, the USGS adds continued summit intrusions and the end of the eruption as other possibilities.

However, at present the greatest volcanic hazard continues to be the emissions, currently carried by southerly winds to impact nearby communities. Between episodes, the vents continue to emit roughly 1,000 to 5,000 tonnes of SO2 per day, which while low-level compared to the output during fountaining episodes on the order of 200,000 tonnes, is still much greater than industrial standards. While trade winds are forecast to return over the weekend, another disruption is expected at the start of next week, again increasing the potential for vog in nearby communities. Both during and between episodes and new outbreaks, vog and tephra remain the most common hazards for island residents, and the usual precautions and preparations apply, especially for those with respiratory sensitivities – more information at https://vog.ivhhn.org/. As usual, we summarize the monitoring signals, imagery, and reports available courtesy of the USGS Hawaiian Volcano Observatory as well as our broader community, annotating the presentation on-screen and discussing live viewer questions as we go.