Kilauea volcano is about to do it again. The Hawaiian Volcano Observatory expects a 47th episode of lava fountaining to erupt inside the summit crater as early as the evening of May 12, 2026, and no later than May 14, extending a rapid-fire eruptive sequence that has produced 46 separate bursts since December 23, 2024. The most powerful of those bursts, Episode 45, launched molten rock 900 feet into the sky above Halemaumau crater, the tallest fountain measured in this cycle, according to the USGS episode-by-episode timeline, which logs approximate maximum fountain heights for each burst.
That is 46 eruptions in roughly five months, a pace that has turned Kilauea’s summit into one of the most closely watched volcanic stages on the planet.
What the instruments are showing
The forecast for Episode 47 comes from tiltmeter data at the summit, which tracks the subtle swelling and deflating of the ground as magma moves beneath the surface. Each eruption follows a recognizable cycle: the crater floor inflates as fresh magma rises into a shallow reservoir, then deflates rapidly once a vent opens and lava fountains begin. After 46 repetitions, scientists at HVO have calibrated their models well enough to issue forecast windows days in advance.
The daily update issued May 12, 2026, places the most likely onset of Episode 47 on the evening of May 12 or during May 13, with an outer bound of May 14. The observatory describes the summit eruption as “paused” during the current quiet interval, meaning lava output has temporarily stopped but the broader eruptive cycle has not ended. Because this forecast window has not been independently verified against the full text of that specific bulletin, readers should confirm the dates directly on the HVO page linked above.
The USGS maintains a detailed episode-by-episode timeline logging start and stop times, approximate maximum fountain heights, and estimated erupted volumes for each burst. That dataset confirms the 46-episode count and documents the stop-and-go rhythm that has defined this eruption from the start.
How tall the fountains have reached
Not every episode is equal. Episode 45 set the benchmark at 900 feet (about 270 meters), a column of lava taller than a 70-story building. Episode 46, which ended at 5:22 p.m. local time on May 5, peaked at roughly 650 feet (200 meters), still enormous but 250 feet shorter than its predecessor. Both height figures are drawn from the USGS episode timeline, which records approximate maximum fountain heights for each episode; readers seeking the precise dated HVO update that first reported each measurement should consult the observatory’s archived daily notices for the relevant episode dates. That spread between consecutive episodes illustrates a key reality: fountain height depends on variables that tiltmeters can only partially capture, including how much dissolved gas remains in the ascending magma and how wide the vent opens when the surface breaks.
HVO does not forecast specific fountain heights for upcoming episodes. The 900-foot figure refers to the confirmed peak of Episode 45, not a prediction for Episode 47. Whether the next burst matches, exceeds, or falls short of that mark will depend on subsurface conditions that only become clear once lava reaches the surface.
What this means for visitors and pilots
The eruption site sits inside a closed zone of Hawaii Volcanoes National Park. The National Park Service restricts access to the immediate summit area but keeps distant overlooks available when conditions allow. Rangers adjust viewing areas, traffic controls, and safety perimeters with each new episode based on fountain height, wind direction, and the risk of rockfall along the caldera rim. On clear nights during active fountaining, the orange glow above Halemaumau is visible for miles.
The park refers to the situation as an “ongoing summit eruption” in its visitor guidance, a framing that differs slightly from HVO’s “paused” language. Both are accurate from different angles, but the distinction matters for trip planning. “Paused” signals that a new burst is imminent. “Ongoing” conveys that hazards persist even between episodes, including volcanic haze known as vog, which can irritate airways and reduce visibility across the summit district and communities downwind.
For aviation, HVO updates the volcano’s alert level and aviation color code in real time on its updates page. Pilots and airlines use those codes to reroute flights when ash reaches altitudes that could damage jet engines. Recent episodes have been short, intense, and largely confined to the crater, limiting ash dispersal beyond the immediate summit. But that pattern could shift if magma interacts with groundwater or if vent geometry changes, scenarios HVO monitors continuously.
What scientists still do not know
Publicly available erupted volume figures for Episodes 44 through 46 have not yet appeared in the USGS episode timeline, which is the primary public record of per-episode volume estimates. That gap makes it difficult to determine whether total lava output is accelerating or holding steady across the sequence. Without consistent volume data, assessments of whether the eruption is intensifying rely on qualitative comparisons of fountain height, episode duration, and the area of fresh lava covering the crater floor.
No injuries or evacuations have been reported during the 46 episodes to date. The eruption has remained confined to Halemaumau crater, well within the closed summit zone, and lava has not threatened any structures or roads. That could change if the eruption migrates to a new vent location on Kilauea’s flanks, a possibility HVO has not forecast but one that the volcano’s history makes worth noting. Kilauea’s 2018 lower East Rift Zone eruption destroyed over 700 homes in the Leilani Estates subdivision, a reminder that this volcano’s hazards extend far beyond the summit.
The forecast window itself carries built-in uncertainty. HVO frames its predictions as probability ranges, not fixed schedules. The tilt-based models have grown more reliable over 46 episodes of calibration, but the magma plumbing beneath Kilauea’s summit is a network of conduits and storage zones that does not always behave identically from one cycle to the next.
How to track Episode 47 as it develops
For now, Halemaumau crater is quiet. Steam drifts from the cooling lava surface. Tiltmeters record the ground slowly swelling again. The pattern of the past five months says the pause will not last long.
Anyone planning to visit the park or living downwind of the summit should check the HVO daily update before traveling. That page carries the current alert level, aviation color code, and the latest forecast window. The National Park Service separately posts closure maps and viewing guidance, including which overlooks are open and whether nighttime viewing of the lava glow is possible.
When Episode 47 begins, it will add another line to the most detailed eruption log in Kilauea’s modern record. For scientists, each burst is another chance to sharpen their forecasting models. For everyone else, it is another chance to watch one of the most active volcanoes on Earth do what it has been doing, with remarkable regularity, since the week before Christmas.
More from Morning Overview
*This article was researched with the help of AI, with human editors creating the final content.
