VONA
What is VONA?

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.

USGS
 

7th of January 2019, 3 years ago

2019-01-07 10:19:00 UTC Orange

Anak Krakatau - 20190107/1019Z 

Windi Cahya Untung, Anak Krakatau Volcano Observatory - 3 years ago

Eruption with ash clouds at 10:16 UTC (17:16 local time). The eruption lasted for 70 seconds Best estimate of ash-cloud top is around 13834 FT (4192 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 .

View
2019-01-07 03:06:00 UTC Orange

Anak Krakatau - 20190107/0306Z 

Windi Cahya Untung, Anak Krakatau Volcano Observatory - 3 years ago

Eruption with ash clouds at 02:56 UTC (09:56 local time). The eruption lasted for 50 seconds Best estimate of ash-cloud top is around 9610 FT (2912 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 .

View
2019-01-07 01:53:00 UTC Orange

Anak Krakatau - 20190107/0153Z 

Windi Cahya Untung, Anak Krakatau Volcano Observatory - 3 years ago

Eruption with ash clouds at 01:47 UTC (08:47 local time). The eruption lasted for 29 seconds Best estimate of ash-cloud top is around 11722 FT (3552 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 .

View
 

6th of January 2019, 3 years ago

2019-01-06 22:53:00 UTC Orange

Anak Krakatau - 20190106/2253Z 

Windi Cahya Untung, Anak Krakatau Volcano Observatory - 3 years ago

Eruption with ash clouds at 22:38 UTC (05:38 local time). The eruption lasted for 82 seconds Best estimate of ash-cloud top is around 11722 FT (3552 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 .

View
2019-01-06 10:45:00 UTC Orange

Anak Krakatau - 20190106/1045Z 

Windi Cahya Untung, Anak Krakatau Volcano Observatory - 3 years ago

Eruption with ash clouds at 10:34 UTC (17:34 local time). The eruption lasted for 46 seconds Best estimate of ash-cloud top is around 11722 FT (3552 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.

View
2019-01-06 09:56:00 UTC Orange

Anak Krakatau - 20190106/0956Z 

Windi Cahya Untung, Anak Krakatau Volcano Observatory - 3 years ago

Eruption with ash clouds at 09:52 UTC (16:52 local time). The eruption lasted for 46 seconds Best estimate of ash-cloud top is around 11722 FT (3552 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 .

View
2019-01-06 09:22:00 UTC Orange

Anak Krakatau - 20190106/0922Z 

Windi Cahya Untung, Anak Krakatau Volcano Observatory - 3 years ago

Eruption with ash clouds at 09:17 UTC (16:17 local time). The eruption lasted for 54 seconds Best estimate of ash-cloud top is around 11722 FT (3552 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.

View
2019-01-06 04:59:00 UTC Orange

Anak Krakatau - 20190106/0459Z 

Windi Cahya Untung, Anak Krakatau Volcano Observatory - 3 years ago

Eruption with ash clouds at 04:44 UTC (11:44 local time). The eruption lasted for 20 seconds Best estimate of ash-cloud top is around 11722 FT (3552 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 .

View
2019-01-06 03:43:00 UTC Orange

Anak Krakatau - 20190106/0343Z 

Windi Cahya Untung, Anak Krakatau Volcano Observatory - 3 years ago

Eruption with ash clouds at 03:37 UTC (10:37 local time). The eruption lasted for 91 seconds Best estimate of ash-cloud top is around 11722 FT (3552 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.

View
2019-01-06 02:30:00 UTC Orange

Anak Krakatau - 20190106/0230Z 

Windi Cahya Untung, Anak Krakatau Volcano Observatory - 3 years ago

Eruption with ash clouds at 02:22 UTC (09:22 local time). The eruption lasted for 776 seconds. Best estimate of ash-cloud top is around 9610 FT (2912 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.

View
 

5th of January 2019, 3 years ago

2019-01-05 04:20:00 UTC Orange

Anak Krakatau - 20190105/0420Z 

Windi Cahya Untung, Anak Krakatau Volcano Observatory - 3 years ago

Eruption with ash clouds at 04:11 UTC (11:11 local time). The eruption lasted for 65 seconds. Best estimate of ash-cloud top is around 17002 FT (5152 M) above sea level, may be higher than what can be observed clearly. Source of height data: ground observer. Ash cloud is moving to west-southwest.

View
2019-01-05 04:00:00 UTC Orange

Anak Krakatau - 20190105/0400Z 

Windi Cahya Untung, Anak Krakatau Volcano Observatory - 3 years ago

Eruption with ash clouds at 02:00 UTC (09:00 local time). The eruption is continouing 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. Ash cloud is moving to north-northeast. ash cloud height is not visible .

View
 

4th of January 2019, 3 years ago

2019-01-04 12:01:00 UTC Orange

Anak Krakatau - 20190104/1201Z 

Nur Rokhman Hidayat, A.Md., Anak Krakatau Volcano Observatory - 3 years ago

Eruption with ash clouds at 07:21 UTC (14:21 local time). The eruption lasted for 187 seconds. Best estimate of ash-cloud top is around 22282 FT (6752 M) above sea level, may be higher than what can be observed clearly. Source of height data: ground observer. Ash-cloud moving to North - NorthEast..

View
2019-01-04 06:01:00 UTC Orange

Anak Krakatau - 20190104/0601Z 

Deny Mardiono, A.Md., Anak Krakatau Volcano Observatory - 3 years ago

Eruption with volcanic ash cloud at 0530 UTC (1230 local). Eruption and ash emission is continuing. Best estimate of ash-cloud top is around 17002 FT (5152 M) above sea level, may be higher than what can be observed clearly. Source of height data: ground observer. Ash-cloud moving to north-northeast..

View
2019-01-04 01:34:00 UTC Orange

Anak Krakatau - 20190104/0134Z 

Nur Rokhman Hidayat, A.Md., Anak Krakatau Volcano Observatory - 3 years ago

Eruption with volcanic ash clouds at 01:31 UTC (08:31 local time). The eruption lasted for 50 seconds Best estimate of ash-cloud top is around 8554 FT (2592 M) above sea level, may be higher than what can be observed clearly. Source of height data: ground observer. Ash clouds is moving to north-northeast.

View
VONA Color Code

Volcano 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.