Based on visual observations, CVGHM reported that on 19 June an ash plume from Batu Tara rose to an altitude of 1.7 km (5,600 ft) a.s.l. Clouds inhibited visual observations on the other days during 18-25 June. The Alert Level remained at 2 (on a scale of 1-4).

Geological Summary. The small isolated island of Batu Tara in the Flores Sea about 50 km N of Lembata (fomerly Lomblen) Island contains a scarp on the eastern side similar to the Sciara del Fuoco of Italy's Stromboli volcano. Vegetation covers the flanks to within 50 m of the summit. Batu Tara lies north of the main volcanic arc and is noted for its potassic leucite-bearing basanitic and tephritic rocks. The first historical eruption, during 1847-52, produced explosions and a lava flow.

Source: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM)