VONA stands for Volcano Observatory Notice for Aviation. It issues reports for changes, both increases and decreases, in volcanic activities, providing a description on the nature of the unrest or eruption, potential or current hazards as well as likely outcomes. See the following link (USGS) for further details. The Center for Volcanology and Geological Hazard Mitigation (CVGHM) under the Geological Agency of the Indonesian Ministry of Energy and Mineral Resources produced VONA's reports based on analysis of data from the agency's monitoring networks as well as from direct observations. VONA's alert levels are color-coded to indicate the different types of notifications addressing specific informative needs. The reports are disseminated via email to national and international stakeholders in the aviation sector. Other interested parties can avail of them through email subscription. All notifications are publicly available online.
USGS13th of April 2017, 5 years ago
Eruption with ash clouds at 11:14 UTC (18:14 local time). The eruption lasted for 240 seconds. Best estimate of ash-cloud top is around 41818 FT (12672 M) above sea level, may be higher than what can be observed clearly. Source of height data: ground observer. Ash cloud is moving to south-Southwest..
ViewEruption with ash clouds at 00:17 UTC ( 07:17 local time). The eruption lasted for 173 seconds. Best estimate of ash-cloud top is around 36538 FT (11072 M) above sea level, may be higher than what can be observed clearly. Source of height data: ground observer. Ash-cloud moving to east.
View12th of April 2017, 5 years ago
Eruption with volcanic ash cloud at 2250 UTC (0750 local). Best estimate of ash-cloud top is around 19272 FT (5840 M) above sea level, may be higher than what can be observed clearly. Source of height data: ground observer. Ash cloud moving to southwest..
ViewEruption with volcanic ash cloud at 2141 UTC (0641 local). Best estimate of ash-cloud top is around 23539 FT (7133 M) above sea level, may be higher than what can be observed clearly. Source of height data: ground observer. Ash cloud moving to west - southwest..
ViewEruption with ash clouds at 16:57 UTC (23:57 local time). The eruption lasted for 224 seconds Best estimate of ash-cloud top is around 38650 FT (11712 M) above sea level, may be higher than what can be observed clearly. Source of height data: ground observer. Ash-cloud moving to east..
ViewEruption with ash clouds at 14:08 UTC ( 21:08 local time). The eruption lasted for 255 seconds. Best estimate of ash-cloud top is around 62515 FT (18944 M) above sea level, may be higher than what can be observed clearly. Source of height data: ground observer. Ash-cloud moving to east..
ViewSudden increase of Deep Volcanic earthquake since 0927 UTC (1827 local). Visual observation does not show any sign of eruption. Best estimate of ash-cloud top is around 0 FT (0 M) above sea level, may be higher than what can be observed clearly. Source of height data: ground observer. No eruption observed..
ViewEruption with volcanic ash cloud at 0731 UTC (1631 local). Best estimate of ash-cloud top is around 22483 FT (6813 M) above sea level, may be higher than what can be observed clearly. Source of height data: ground observer. Ash cloud moving to south..
View11th of April 2017, 5 years ago
Eruption with volcanic ash cloud at 2322 UTC (0822 local). Best estimate of ash-cloud top is around 18216 FT (5520 M) above sea level, may be higher than what can be observed clearly. Source of height data: ground observer. Ash cloud moving to south..
ViewEruption with volcanic ash cloud at 2234 UTC (0734 local). Best estimate of ash-cloud top is around 21427 FT (6493 M) above sea level, may be higher than what can be observed clearly. Source of height data: ground observer. Ash cloud moving to west..
ViewEruption with volcanic ash cloud at 0922 UTC (1822 local). Best estimate of ash-cloud top is around 19315 FT (5853 M) above sea level, may be higher than what can be observed clearly. Source of height data: ground observer. Ash cloud moving to south..
ViewEruption with ash clouds at 04:20 UTC (11:20 local time). The eruption lasted for 356 seconds Best estimate of ash-cloud top is around 59770 FT (18112 M) above sea level, may be higher than what can be observed clearly. Source of height data: ground observer. Ash cloud is moving to southeast.
ViewEruption produce volcanic ash cloud at 0106 UTC (1006 local). Best estimate of ash-cloud top is around 16104 FT (4880 M) above sea level, may be higher than what can be observed clearly. Source of height data: ground observer. Ash cloud moving to south..
View10th of April 2017, 5 years ago
Eruption with ash clouds at 23:38 UTC ( 06:38 local time). The eruption lasted for 90 seconds. Best estimate of ash-cloud top is around 41818 FT (12672 M) above sea level, may be higher than what can be observed clearly. Source of height data: ground observer. Ash cloud is moving to east -southeast.
ViewVolcano is in normal, non-eruptive state, or, after a change from a higher level: Volcanic activity considered to have ceased, and volcano reverted to its normal, non-eruptive state.
Volcano is experiencing signs of elevated unrest above known background levels, or, after a change from higher level: Volcanic activity has decreased significantly but continues to be closely monitored for possible renewed increase.
Volcano is exhibiting heightened unrest with increased likelihood of eruption with column height below 6000 meter above sea level.
Eruption is forecast to be imminent with significant emission of ash with column height above 6000 meter above sea level.