(1) VOLCANO OBSERVATORY NOTICE FOR AVIATION (VONA)
(2) Issued:	(20170128/0043Z)
(3) Volcano:	Bogoslof (VNUM #311300)
(4) Current Color Code:	ORANGE
(5) Previous Color Code:	RED
(6) Source:	Alaska Volcano Observatory
(7) Notice Number:	2017/A53
(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:	No further ash emissions have occurred at Bogoslof volcano since the explosion today at 08:24 AKST (17:24 UTC). No detectable activity observed in seismic, infrasound or lightning data. We are therefore lowering the Aviation Color Code to ORANGE and the Alert Level to WATCH. Significant ash-producing explosions could occur at any time, with no detectable precursors. Low-level activity below our detection limit is possible and may present a hazard in the immediate vicinity of the island. The volcanic cloud from the eruption this morning has dissipated and the SIGMET aviation warning message that is issued by the National Weather Service expired today at 11:15 AKST (2215 UTC)
(12) Volcanic cloud height:	none observed
(13) Other volcanic cloud information:	n/a
(14) Remarks:
(15) Contacts:	Michelle Coombs, Scientist-in-Charge, USGS mcoombs@usgs.gov (907) 786-7497 Jessica Larsen, Acting Coordinating Scientist, UAF jflarsen@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: WATCH
Previous Volcano Alert Level: WARNING

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

Issued: Friday, January 27, 2017, 3:43 PM AKST
Source: Alaska Volcano Observatory
Notice Number: 2017/A53
Location: N 53 deg 55 min W 168 deg 2 min
Elevation: 492 ft (150 m)
Area: Aleutians

Volcanic Activity Summary: No further ash emissions have occurred at Bogoslof volcano since the explosion today at 08:24 AKST (17:24 UTC). No detectable activity observed in seismic, infrasound or lightning data. We are therefore lowering the Aviation Color Code to ORANGE and the Alert Level to WATCH. Significant ash-producing explosions could occur at any time, with no detectable precursors. Low-level activity below our detection limit is possible and may present a hazard in the immediate vicinity of the island.

The volcanic cloud from the eruption this morning has dissipated and the SIGMET aviation warning message that is issued by the National Weather Service expired today at 11:15 AKST (2215 UTC)

Recent Observations:
[Volcanic cloud height] none observed
[Other volcanic cloud information] n/a

Contacts: Michelle Coombs, Scientist-in-Charge, USGS
mcoombs@usgs.gov (907) 786-7497

Jessica Larsen, Acting Coordinating Scientist, UAF
jflarsen@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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