(1) VOLCANO OBSERVATORY NOTICE FOR AVIATION (VONA)
(2) Issued:	(20170624/0220Z)
(3) Volcano:	Bogoslof (VNUM #311300)
(4) Current Color Code:	RED
(5) Previous Color Code:	ORANGE
(6) Source:	Alaska Volcano Observatory
(7) Notice Number:
(8) Volcano Location:	N 53 deg 55 min W 168 deg 2 min
(9) Area:	Aleutians
(10) Summit Elevation:	492 ft (150 m)
(11) Volcanic Activity Summary:	A significant explosive eruption at Bogoslof volcano occurred at 00:49 UTC, June 24 (16:49 AKDT, June 23) and lasted about 10 minutes. The eruption produced a volcanic cloud that reached about 36,000 ft above sea level, and was accompanied by strong seismcity, lightning and infrasound. Thus, AVO is raising the Aviation Color Code to RED and Alert level to WARNING for Bogoslof volcano. Satellite data through 1:30 UTC shows a volcanic cloud with an estimated altitude of 36,000 ft asl moving towards the northeast. Seismic and infrasound data suggest that the ash emissions are no longer continuing. The volcano is in a restless condition and additional explosive events may occur.
(12) Volcanic cloud height:	36,000 ft asl estimated by satellite and pilot report of cloud to 30,000 ft asl.
(13) Other volcanic cloud information:	Cloud moving towards northeast
(14) Remarks:	The SIGMET warning message for aviation, issued by the National Weather Service Alaska Aviation Weather Unit currently is in effect up to 36,000 ft above sea level. Status of the ash cloud forecast can be found at their website at http://www.weather.gov/aawu/sigmets No ash fallout is expected in populated areas, as the ash cloud is expected to be transported out over the ocean.
(15) Contacts:	Dave Schneider, Acting Scientist-in-Charge, USGS djschneider@usgs.gov (907) 786-7497 Jeff Freymueller, Coordinating Scientist, UAF jfreymueller@alaska.edu (907) 322-4085
(16) Next Notice:

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AVO/USGS Volcanic Activity Notice

Volcano: Bogoslof (VNUM #311300)

Current Volcano Alert Level: WARNING
Previous Volcano Alert Level: WATCH

Current Aviation Color Code: RED
Previous Aviation Color Code: ORANGE

Issued: Friday, June 23, 2017, 6:20 PM AKDT
Source: Alaska Volcano Observatory
Notice Number:
Location: N 53 deg 55 min W 168 deg 2 min
Elevation: 492 ft (150 m)
Area: Aleutians

Volcanic Activity Summary: A significant explosive eruption at Bogoslof volcano occurred at 00:49 UTC, June 24 (16:49 AKDT, June 23) and lasted about 10 minutes. The eruption produced a volcanic cloud that reached about 36,000 ft above sea level, and was accompanied by strong seismcity, lightning and infrasound. Thus, AVO is raising the Aviation Color Code to RED and Alert level to WARNING for Bogoslof volcano.

Satellite data through 1:30 UTC shows a volcanic cloud with an estimated altitude of 36,000 ft asl moving towards the northeast. Seismic and infrasound data suggest that the ash emissions are no longer continuing. The volcano is in a restless condition and additional explosive events may occur.

Recent Observations:
[Volcanic cloud height] 36,000 ft asl estimated by satellite and pilot report of cloud to 30,000 ft asl.
[Other volcanic cloud information] Cloud moving towards northeast

Hazard Analysis:
[Ashfall] Possible trace ash fall over Bering Sea northeast of the volcano

Remarks: The SIGMET warning message for aviation, issued by the National Weather Service Alaska Aviation Weather Unit currently is in effect up to 36,000 ft above sea level. Status of the ash cloud forecast can be found at their website at http://www.weather.gov/aawu/sigmets

No ash fallout is expected in populated areas, as the ash cloud is expected to be transported out over the ocean.

Contacts: Dave Schneider, Acting Scientist-in-Charge, USGS
djschneider@usgs.gov (907) 786-7497

Jeff Freymueller, Coordinating Scientist, UAF
jfreymueller@alaska.edu (907) 322-4085


The Alaska Volcano Observatory is a cooperative program of the U.S. Geological Survey, the University of Alaska Fairbanks Geophysical Institute, and the Alaska Division of Geological and Geophysical Surveys.

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