This 7x-speed footage captures a massive pyroclastic flow racing down Indonesia’s Mount Semeru as the volcano unleashed a powerful eruption. | AccuWeather

583K views · 6K reactions | When a volcano erupts, pyroclastic flows are often the biggest danger to anyone nearby. These fast-flowing currents of rock, ash and hot gas are extremely difficult to study, so researchers created their own. Read the related Nature Geoscience paper here: https://go.nature.com/2Im1bYs | Nature Portfolio | Facebook

🇮🇩 Pyroclastic Flow on Mount Semeru 🌋🔥🌫On January 15, 2026, a pyroclastic flow descended from Mount Semeru (Java, Indonesia). Hot gases, ash, and rock fragments rushed down the slopes, covering nearby areas. Authorities declared a heightened danger level, advising residents to evacuate from the hazardous zone. Preliminary reports indicate that information on casualties is still being verified. #Indonesia #Semeru #volcano #pyroclasticflow #weather | Val Sab

WATCH: Effusive eruption at Mayon Volcano continues for the 23rd consecutive day, generating incandescent lava flows, pyroclastic density currents (PDC) or “uson,” and rockfall. Lava flows have reached radial distances from the crater of 3.7 km in the Basud (east), 1.6 km in the Bonga (southeast), and 1.3 km in the Mi-isi Gullies as of Thursday, Jan. 29, 2026. Alert Level 3 prevails over Mayon and entry into the 6-km Permanent Danger Zone must be prohibited. Courtesy: PHIVOLCS/X | GMA News