A spinning column of volcanic ash rose beside Kilauea’s summit vents on June 1, 2026, just minutes after one of the longest lava-fountaining episodes in the volcano’s current eruption came to an end. The whirlwind, known in Hawaiian as a puahiohio, formed at 4:47 p.m. HST and was recorded by a USGS monitoring camera stationed on the crater rim. Episode 48 of the eruption had run for roughly nine hours, sending molten rock as high as 650 feet and spreading lava across about 40 percent of the crater floor before the vortex appeared in its steaming aftermath.
Nine hours of fountaining and a 650-foot peak set the stage
Kilauea has been erupting in stop-and-start bursts from the same north and south vents since Dec. 23, 2024, and scientists count each pause-separated pulse as a distinct episode. Episode 48 began at 4:40 a.m. HST and ended at 1:37 p.m. HST, lasting approximately nine hours, according to the Hawaiian Volcano Observatory notice. Fountains topped out at roughly 650 feet (200 m), and fresh lava flows covered an estimated 40 percent of the crater, scattering strands of Pele’s hair across downwind areas.
Those conditions matter for what happened next. A crater floor still radiating extreme heat, combined with lingering steam and fine ash particles suspended in turbulent air, can create sharp temperature gradients near the surface. When those gradients are steep enough, rising columns of hot air begin to rotate, producing short-lived vortices that sweep loose tephra upward. The whirlwind that the V1cam caught at 4:47 p.m. HST formed roughly three hours after active fountaining stopped, while the ground was still hot enough to generate vigorous convection.
HVO geologist Katie Mulliken has explained that the observatory counts episodes by the pauses between them from the same vents in the same eruption. That counting method is what pushed the tally to 48, a record for any single Kilauea eruption. The distinction is not just bookkeeping: each episode delivers fresh lava to the crater floor, progressively raising the thermal baseline and expanding the area that can generate convective updrafts once fountaining pauses.
By the time episode 48 wound down, the crater floor had been resurfaced dozens of times. Layers of still-warm lava slabs, interspersed with fresh, glassy crust, created a patchwork of hot spots. Even as visible fountains ceased, those surfaces continued to radiate heat into the overlying air. The resulting buoyant plumes were invisible to the naked eye but became obvious in their effects once the vortex took shape.
What the V1cam footage and HVO logs reveal together
The USGS published the summit camera footage of the whirlwind alongside a broader photo and video chronology of episode 48. In the footage, the vortex appears as a narrow, rapidly spinning funnel of gray-brown ash that rises from the steaming crater floor near the vent area. The surrounding ground is visibly hot, with plumes of white steam drifting across the frame.
The funnel’s base repeatedly lifts and reforms as it moves over different parts of the crater floor, suggesting a delicate balance between the rising hot air and the surrounding wind field. At times, the vortex narrows into a tight column, then briefly widens and becomes more diffuse before tightening again. That pulsing behavior is typical of dust devils and other small-scale convective vortices, but in this case the “dust” is a mixture of fine ash, Pele’s hair, and other loose volcanic fragments.
Pairing the video timestamp with the observatory’s fountain-height logs raises a testable question: does whirlwind formation become more likely when an episode runs longer than eight hours and covers more than about 35 percent of the crater? Episode 48 exceeded both thresholds, with its nine-hour duration and 40 percent lava coverage. Earlier, shorter episodes in the same eruption sequence did not produce documented whirlwinds of comparable size, though the absence of a systematic catalog makes direct comparison difficult. The episode 48 chronology provides timestamped visual evidence that could, in principle, be cross-referenced with fountain-height measurements to test this pattern across all 48 episodes.
For now, that pattern remains an informed hypothesis rather than a confirmed rule. The camera network does not capture every corner of the crater, and smaller vortices may go unnoticed when visibility is poor or when cameras are focused on active vents rather than the broader floor. Still, the June 1 event stands out for its clarity and timing: it occurred after one of the longest and most vigorous bursts of activity in the current eruption, and it developed squarely within the field of view of an operating camera.
The practical hazard is real. Hawaiʻi Volcanoes National Park and stretches of Highway 11 were closed because of falling tephra and volcanic fragments during the broader fountaining sequence. A whirlwind that lofts fine ash particles after an episode officially ends extends the window of airborne hazard beyond what the fountaining timeline alone would suggest. Visitors and residents downwind face exposure to abrasive particulates even when the lava fountains themselves have stopped.
In addition to respiratory concerns, ash-laden vortices can reduce visibility for drivers and hikers, and they can carry lightweight volcanic glass well beyond the crater rim. Even without reaching populated areas, such events complicate decisions about when to reopen trails, overlooks, and roadways. Managers must weigh the apparent calm of a quiet crater against the lingering potential for convective wind phenomena that stir up residual ash.
Gaps in the record and what to watch next
No published USGS data describe the internal wind speed, temperature, or particle size within the June 1 whirlwind. The V1cam captures the vortex visually, but the observatory has not released instrumental measurements from inside or immediately adjacent to it. Without those numbers, the intensity of the vortex and the size of particles it carried remain open questions. The Smithsonian Institution’s weekly volcanic activity report for the mid-June period compiled plume and ash observations for Kilauea but relied on observatory summaries rather than raw seismic or gas-flux records for the specific post-episode window when the whirlwind formed.
Ground-level observations are similarly sparse. The summit area was under restricted access because of the ongoing eruption, so there are no public reports from park visitors or guides who might have seen the vortex from other angles. That absence of eyewitness accounts leaves the camera footage as the primary record, limiting how precisely scientists can reconstruct the vortex’s height, width, and motion across the crater floor.
Those gaps highlight a broader challenge in monitoring small, transient volcanic phenomena. Instrument networks at active volcanoes are optimized for detecting magma movement, gas emissions, and larger-scale hazards such as major ash plumes or lava flows. Short-lived vortices that last only minutes fall into a gray area: they can pose localized risks but are difficult to anticipate and even harder to measure directly.
Looking ahead, researchers may turn to indirect methods to better characterize events like the June 1 puahiohio. High-resolution time-lapse imagery from multiple cameras could allow rough estimates of rotation speed and column height, especially if synchronized with wind and temperature data from summit weather stations. Machine-learning tools could scan archives of summit footage to flag other, previously overlooked vortices, building a more complete catalog of when and where they form.
Any such effort would benefit from tighter integration between hazard notices, visual chronologies, and raw monitoring data. The June 1 whirlwind was documented because it happened to occur in clear view of a camera during an already notable episode. Systematically linking camera timestamps with fountain intensity, crater coverage, and meteorological conditions could turn that one-off observation into a stepping stone toward understanding how Kilauea’s evolving crater floor influences the atmosphere just above it.
For residents and visitors, the takeaway is straightforward: hazard windows around Kilauea’s summit do not end the moment lava fountains shut off. As long as fresh lava continues to heat the crater floor and fine ash remains available to be lofted, convective vortices like the June 1 puahiohio can briefly revive airborne risks. Continued monitoring, careful interpretation of visual records, and conservative access policies will be key to managing those risks as the eruption’s record-setting series of episodes continues.
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*This article was researched with the help of AI, with human editors creating the final content.
