Observers at Babadan west and Kaliurang south of the mountain reported hearing an avalanche on 12 September 2010. On 13 September 2010 white plumes were observed rising above the crater. Lava dome inflation, detected since March, increased from background levels of to per day to a rate of per day on 16 September. On 19 September 2010 earthquakes continued to be numerous, and the next day CVGHM raised the Alert Level to 2 (on a scale of 1–4). Lava from Mount Merapi in Central Java began flowing down the Gendol River on 23–24 October signalling the likelihood of an imminent eruption.