PVMBG reported that at 0853 on 19 February a large explosive event at Sinabung generated a dark gray plume with a high volume of ash that rose at least to 16.8 km (55,000 ft) a.s.l.
According to the Darwin VAAC, ash plumes that were identified in satellite images, recorded by webcams, and reported by PVMBG continued to rise throughout the day to 13.7 km (45,000 ft) a.s.l.
and drift 320 km NNW.
Parts of the ash plumes drifted in multiple directions at lower altitudes.
As many as 10 pyroclastic flows were observed, traveling as far as 4.9 km SSE and 3.5 km E.
Ash and tephra as large as pebbles fell in areas downwind including Simpang Empat (7 km SE), the Namanteran district, Pqyung (5 km SSW), Tiganderket (7 km W), Munthe, Kutambaru (20 km NW), Perbaji (4 km SW), and Kutarayat.
Conditions in five districts were so dark that visibility was only about 5 m.
Some residents outside of the evacuation zone self-evacuated.
The event was possibly the largest since the beginning of the current eruption, which began in September 2013.
The Alert Level remained at 4 (on a scale of 1-4), with a general exclusion zone of 3 km and extensions of 7 km on the SSE sector, 6 km in the ESE sector, and 4 km in the NNE sector.
Sources: Badan Nacional Penanggulangan Bencana (BNPB) ,Darwin Volcanic Ash Advisory Centre (VAAC),Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM),Rocky Planet