According to the KVERT, an ash explosion was observed at Zhupanovsky on 16 September at 23:41 UTC via the Himawari-8 satellite. It was accompanied by an ash plume of about 6,000 - 7,000 m asl height. drifting south-west for about twenty kilometers.
A second explosion followed 33 minutes later, with a high plume of 8,000 meters, drifting this time for about ten kilometers.
The activity continued on 17 September with the emission of a plume of steam and gas of a height of 4,000 meters asl.
The aviation code returned to yellow, after a few hours to orange.
Sources: KVERT & VAAC Tokyo
Strombolian activity marked the Sinabung on 17 September, characterized by plumes of different colors, surmounting a nearby dome, always threatening the collapse.
The seismographs recorded three eruptions, and the observatory observed a column of ashes high of 1100 - 2000 meters, and some falls of ash on the Sinabung station.
Fears concern the Laborus River where a dam was formed upstream following pyroclastic flows. The PVMBG reports the formation of a lake that grows in size and could be responsible for a lahar or flash flood, following a collapse of this dam.
Sources: PVMBG & Beidar Sinabung