The number of VLP seismic events (standard values 5-12) is high, 15 events/hour.

The amplitude of seismic tremor is medium.

The infrasonic activity is medium. The acoustic pressure of explosions is low, 0.4 bar (standard values <1 bar). The amplitude of puffing is low, ~40 mbar.

Tiltmeters analysis does not show any significant deformation of the volcano edifice

Thermal activity of explosive events is not available. The number of thermal transients in the NE sector of the crater(standard = 100) is not available. The amplitude of thermal transients is not available. Exit velocity of pyroclasts, estimated through thermal camera analysis, is not available.

MODIS thermal anomalies are low: 6 MW (13:10 UTC yesterday).

Rockfall activity is medium. The number of rockfalls is 7 per day.

SO₂ flux in the NE sector of the crater terrace is low, 46 t/d

CO₂ flux based on the C/S of 13.79 mesured at 15:20 UTC on 2025/09/24 is medium, 649 t/d

Indice di Attività Vulcanica: medium

• Seismic (VLP) rate HIGH
• Seismic tremor MEDIUM
• Puffing LOW
• Acustic pression of explosions LOW
• Thermal activity NOT AVAILABLE
• SO₂ flux LOW
• CO₂ flux MEDIUM
• Rockfall activity MEDIUM

In the last 24h, Stromboli volcano showed MEDIUM degassing activity (puffing/spattering with values of about 40 mbar), associated with a MEDIUM explosive activity (max. acoustic pressure 1 bar) located mainly at the SW sectors. The volcanic tremor shows MEDIUM values. The number of VLP events is HIGH (15 events/hour). MODIS and VIIRS satellite images show BASSI thermal anomalies (6 MW). SO2 flux is LOW (46 t/d). The CO2 flux is MEDIUM (daily mean flux of 649 t/d based on a C/S ratio of 13.79 measured 24/09/2025 at 15:20 UTC). The rockfall activity is MEDIUM, with 7 event(s) detected in the past 24 hours. The Volcanic Activity Index is MEDIUM.