(1) VOLCANO OBSERVATORY NOTICE FOR AVIATION (VONA)
(2) Issued:	(20170218/0134Z)
(3) Volcano:	Bogoslof (VNUM #311300)
(4) Current Color Code:	RED
(5) Previous Color Code:	RED
(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:	Another short-lived explosive eruption occurred today at about 15:46 AKST (00:46 UTC) as detected in seismic and infrasound data. A volcanic cloud is visible in satellite and is as high as 25,000 ft asl. No lightning was associated with this event. Seismicity as detected on nearby islands is back to low levels, but Bogoslof volcano remains at a heightened state of unrest and in an unpredictable condition. Additional explosions producing high-altitude volcanic clouds could occur at any time. Low-level explosive activity that is below our ability to detect in our data sources may be occurring. These low-level explosions could pose a hazard in the immediate vicinity of the volcano. The Aviation Color Code remains at RED and the Alert Level remains at WARNING.
(12) Volcanic cloud height:	SIGMET to 25,000 ft asl
(13) Other volcanic cloud information:	Winds are to the north
(14) Remarks:	The SIGMET warning message for aviation, issued by the National Weather Service Alaska Aviation Weather Unit, currently is in effect up to 25,000 ft above sea level. Status of the ash cloud forecast can be found at their website at http://aawu.arh.noaa.gov/ No ash fallout is expected in populated areas as winds are to the north.
(15) Contacts:	Michelle Coombs, Scientist-in-Charge, USGS mcoombs@usgs.gov (907) 786-7497 Jeff Freymueller, Coordinating Scientist, UAFGI jfreymueller@alaska.edu (907) 322-4085
(16) Next Notice:

---

AVO/USGS Volcanic Activity Notice

Volcano: Bogoslof (VNUM #311300)

Current Volcano Alert Level: WARNING

Current Aviation Color Code: RED

Issued: Friday, February 17, 2017, 4:34 PM AKST
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: Another short-lived explosive eruption occurred today at about 15:46 AKST (00:46 UTC) as detected in seismic and infrasound data. A volcanic cloud is visible in satellite and is as high as 25,000 ft asl. No lightning was associated with this event.

Seismicity as detected on nearby islands is back to low levels, but Bogoslof volcano remains at a heightened state of unrest and in an unpredictable condition. Additional explosions producing high-altitude volcanic clouds could occur at any time. Low-level explosive activity that is below our ability to detect in our data sources may be occurring. These low-level explosions could pose a hazard in the immediate vicinity of the volcano.

The Aviation Color Code remains at RED and the Alert Level remains at WARNING.

Recent Observations:
[Volcanic cloud height] SIGMET to 25,000 ft asl
[Other volcanic cloud information] Winds are to the north

Hazard Analysis:
[Ashfall] None expected on communities at this time, winds are to the north.

Remarks: The SIGMET warning message for aviation, issued by the National Weather Service Alaska Aviation Weather Unit, currently is in effect up to 25,000 ft above sea level. Status of the ash cloud forecast can be found at their website at http://aawu.arh.noaa.gov/

No ash fallout is expected in populated areas as winds are to the north.

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

Jeff Freymueller, Coordinating Scientist, UAFGI
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.

---