Kilauea Eruption

Episode 48 Forecast: May 22-26, 2026

USGS Hawaiian Volcano Observatory forecasts Episode 48 between Friday, May 22 and Tuesday, May 26. Summit inflation has been climbing steadily since Episode 47 ended on May 15, with the Uēkahuna tiltmeter recording approximately 6.8 microradians of inflationary tilt in five days — a rate of about 2 microradians per day. Based on the pattern from Episodes 44-47, the threshold for the next episode sits around 8-10 microradians.

Both eruptive vents continue to glow, and incandescence remains visible on the crater floor as Episode 47 lava cools. Lava spattering and overflows from one or both vents are expected to precede fountaining — this precursory activity has been the tell for the last several episodes, sometimes starting 1-3 days before the main event.

If you're visiting Hawaii Volcanoes National Park this week, there's a real chance you'll witness an eruption. The park typically closes during active fountaining due to tephra hazards but reopens within hours once the episode ends. Check the USGS Kilauea updates page for real-time status.

How USGS Forecasts Kilauea Episodes

HVO's forecast model is surprisingly straightforward. Tiltmeters at the summit measure ground deformation as magma fills the shallow reservoir beneath Halemaʻumaʻu. When tilt reaches the threshold — typically 8-10 microradians of inflation — the reservoir is full enough to trigger a new fountaining episode. The inflation rate (about 2 µrad/day in the current cycle) lets scientists estimate the eruption window with ~3-4 day precision.

It's not perfect — Episode 46 arrived slightly ahead of schedule on May 5, while some earlier episodes were delayed by a day or two. But the model has correctly predicted every episode since late 2025, making this one of the most forecastable eruptions on the planet. Think of it like a pressure cooker with a known capacity: once it's full, something's going to give.

Episode 47 — May 14, 2026

The 47th episode began at 3:27 PM HST on May 14 and ended at 12:27 AM on May 15 — nine hours of continuous lava fountaining from the north vent in Halemaʻumaʻu crater at Kilauea's summit. Maximum fountain height reached about 650 feet (200m).

Episode 47 was notable for its near-identical tilt profile to Episode 46 — both reached 650-foot fountains and lasted 9 hours. This consistency is unusual. Earlier in the cycle, episodes varied wildly, with some hitting 1,400 feet (Episode 39) and others barely reaching 300 feet. The recent stabilization could mean the magma supply rate has settled into a steady state — or it could be the calm before another escalation.

The eruptive plume carried fine ash and Pele's hair (thin strands of volcanic glass) into areas outside the park. Unlike Episode 44's softball-sized reticulite, the tephra from Ep47 was smaller and lighter — more of a nuisance than a hazard. The park remained open throughout.

Episodes 45-46 Recap

Episode 45 (April 23): Erupted right on schedule, 14 days after Episode 44. The north vent produced fountains that occasionally topped 1,000 feet (305m) over 8.5 hours — visible from Hilo, 30 miles away. The wispy trails at the fountain's peak made for spectacular nighttime footage that went viral on social media.

Episode 46 (May 5): A 9-hour episode with 650-foot (200m) fountains from the north vent. The real story was the volcanic plume — it reached 20,000 feet (6,000m) above sea level, the tallest of the entire cycle. Both vents showed precursory lava flows in the days before, but only the north vent produced a full fountain. This was the first time the plume-to-fountain ratio was so high, suggesting more volatile-rich magma.

Episode 44 — April 9, 2026

The 44th episode of lava fountaining began at 11:10 AM HST on April 9, 2026, from the north vent in Halemaʻumaʻu crater at Kilauea's summit. It ended at 7:41 PM — roughly 8.5 hours of continuous activity.

Peak fountain heights hit ~800 feet around 1 PM, with the north vent doing most of the work. Lava covered roughly half the Halemaʻumaʻu crater floor. Chunks of lightweight reticulite (a type of volcanic glass) up to 12 inches across rained down near Kilauea Military Camp and the Volcano Golf Course subdivision. Hawaii Volcanoes National Park closed temporarily, and a stretch of Highway 11 was shut down until around 6 PM.

The Ongoing Eruption Cycle (Dec 2024 – Present)

What started on December 23, 2024 has become one of the most remarkable volcanic events in recent history. Through 47 episodes and counting, Kilauea has been erupting in discrete fountaining episodes from two vents in Halemaʻumaʻu crater — the north vent and south vent. Each episode follows a predictable pattern:

1. Summit inflation builds over 1-4 weeks as magma fills the shallow reservoir
2. Precursory lava oozes from one or both vents, sometimes days before
3. Fountaining begins abruptly, typically from the north vent
4. 6-12 hours of sustained activity with fountains ranging from 30m to 425m
5. Eruption pauses. Deflation begins. Cycle resets.

The cycle went through an intensification phase. Early episodes in January 2025 produced modest 100-160 foot fountains. By mid-2025, heights exceeded 1,000 feet. Episode 39 on December 24, 2025 set the record at approximately 1,400 feet (425m). Since then, recent episodes (46-47) have settled around 650 feet — the magma supply may have stabilized, or a new escalation could be building.

Kilauea Eruption History

Kilauea is one of the most active shield volcanoes on Earth. It's been erupting nearly continuously since 1983, and Hawaiian oral histories record eruptions going back centuries. Here are the major eruption periods:

Kilauea's eruptions are effusive — basaltic lava flows rather than the explosive blasts that characterize stratovolcanoes. Compare this to the explosive 1980 Mount St. Helens eruption or the ongoing Mayon Volcano eruption in the Philippines, where pyroclastic flows pose an immediate threat. Hawaii's shield volcanism makes Kilauea one of the safest active volcanoes in the United States to observe.

Can You Visit Kilauea During an Eruption?

Yes — and millions of people do every year. Hawaii Volcanoes National Park remains open between episodes, and the episodic nature of the current eruption means the park is accessible most of the time.

During active episodes, the park closes temporarily (Episode 44 caused a same-day closure). Between episodes, you can drive to overlooks above Halemaʻumaʻu crater and see the fresh lava flows, steam vents, and — at night — the orange glow from cooling lava.

Kilauea Volcano Tours

Seeing an active volcano is a bucket-list experience. The best way to make the most of a Kilauea visit is with a guided tour — local guides know the best viewpoints, current conditions, and can get you to spots you'd never find on your own. Helicopter tours offer aerial views of the crater and lava flows that are genuinely jaw-dropping.

Frequently Asked Questions