The number of VLP seismic events (standard values 5-12) is high, 16.9 events/hour.

The amplitude of seismic tremor is medium.

The infrasonic activity is medium. The acoustic pressure of explosions is medium, 0.4 bar (standard values <1 bar). The amplitude of puffing is medium, ~34.4 mbar.

Tiltmeters analysis shows a deformation of approximately 0.3 microradians recorded by the OHO tiltmeter, associated with the major eruption that occurred today at 05:12:50 UTC (see Comunicato di Attività Stromboli 12 Giugno 2026)

Thermal activity of explosive events is medium. The number of thermal transients in the NE sector of the crater (standard = 100) is high, 226. The amplitude of thermal transients is low, 3.16 ºF. Exit velocity of pyroclasts, estimated through thermal camera analysis, is low, 15 m/s.

MODIS thermal anomalies are low: 4 MW (12:12 UTC yesterday).

Rockfall activity is high. The number of rockfalls is 11 per day.

SO₂ flux in the NE sector of the crater terrace is medium, 96 t/d

CO₂ flux based on the C/S of 11.41 mesured at 03:20 UTC on 2026/06/11 is medium, 1114 t/d

Indice di Attività Vulcanica: medium

• Seismic (VLP) rate HIGH
• Seismic tremor MEDIUM
• Puffing MEDIUM
• Acustic pression of explosions MEDIUM
• Thermal activity MEDIUM
• SO₂ flux MEDIUM
• CO₂ flux MEDIUM
• Rockfall activity HIGH

The volcanic activity of Stromboli volcano showed MEDIUM degassing activity (puffing/spattering values of about 34.4 mbar) located mainly in the SW sector, associated with MEDIUM explosive activity, located mainly in the NE sector. The volcanic tremor has MEDIUM values. The number of VLP events is HIGH (16.9 events/hour). MODIS and VIIRS satellite images show LOW thermal anomalies (4 MW). SO2 flux is MEDIUM (96 t/d). The CO2 flux is MEDIUM (daily mean flux of 1114 t/d based on a C/S ratio of 11.4 measured 11/06/2026 at 03:20 UTC). The number of rockfalls is HIGH, with 11 events detected in the past 24h. A major explosion occurred at 05:12:50 UTC today (see Comunicato Attività Stromboli 12 Giugno 2026), associated with a seismic signal in the VLP band with a maximum amplitude of 2.0×10 5 m and ground deformation of approximately 0.3 microradians (recorded at the OHO tiltmeter). The explosion generated a maximum infrasonic pressure of 276 Pa localized in the NE crater sector. The volcanic activity index is MEDIUM.