Indonesia's Semeru volcano experienced a significant eruption on November 19, resulting in ash plumes reaching approximately 18 kilometers into the atmosphere. This event prompted the evacuation of at least 300 residents as authorities elevated the alert level to IV, the highest level. Pyroclastic flows were observed moving down the southeastern slopes, particularly impacting the Besuk Kobokan valley. The eruption's effects extended beyond immediate volcanic activity, with ash dispersal affecting multiple directions and continuous emissions reported.