Lava avalanche monitored by surveillance cameras during the observation period from 12:00 to 6:00 a.m Western Indonesian Time (WIB) was flowing upstream of Gendol River, the Head of BPPTKG Hanik Humaida stated.
During the observation time, there were also two volcanic earthquakes monitored with amplitude ranging between 4 to 27 millimeters and lasting between 41.8 to 85 seconds.
In addition to this, visual observation result showed weak-pressured white crater smoke rose 20 meters above the crater's peak.
The wind blew weakly to the direction of southwest and west, while the air temperature was recorded at 13 to 16.9 degrees Celsius; air humidity 45 to 95 percent; and air pressure 568 to 708.7 mmHg.
The BPPTKG maintained the status of Mount Merapi at level 2 or alert, and has temporarily advised against conducting climbing activities apart for disaster mitigation-related investigation and research.
The center has urged residents to not conduct any activities within a three-kilometers radius from the volcano's peak, and called on residents living in the vicinity of Gendol River to intensify vigilance over the extent to which the hot clouds from Merapi will dissipate.
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