(1) VOLCANO OBSERVATORY NOTICE FOR AVIATION (VONA)
(2) Issued:(20130308/1940Z)
(3) Volcano:Cleveland (CAVW# 1101-24-)
(4) Current Color Code:YELLOW
(5) Previous Color Code:orange
(6) Source:Alaska Volcano Observatory
(7) Notice Number:2013/A4
(8) Volcano Location:N 52 deg 49 min W 169 deg 56 min
(9) Area:Aleutians Alaska
(10) Summit Elevation:5676 ft (1730 m)
(11) Volcanic Activity Summary:The summit lava dome extruded in late January 2013 has remained unchanged since the last color code change on February 6, 2013. Anomalous surface temperatures prevalent in late January through mid-February declined and the last thermal anomaly observed in satellite imagery was reported on February 26. Although satellite viewing conditions at Cleveland are typically cloudy, clear views between March 1 and 5 indicate no change has occurred in the summit dome and thermal anomalies no longer are present. Therefore, the Aviation Color Code and Volcano Alert Level for Cleveland is lowered to YELLOW/ADVISORY.

The last confirmed explosion at Cleveland occurred in November, 2012. The presence of a lava dome in the summit crater means that explosions of blocks and ash could occur with little or no warning. Ash clouds, if produced, could exceed 20,000 feet above sea level. If a large ash-producing event occurs, nearby seismic, infrasound, or volcanic lightning networks should alert AVO staff. However, for some events, a delay of several hours is possible. There is no real-time seismic monitoring network on Mount Cleveland and AVO is unable to track activity in real time.
(12) Volcanic cloud height:Unknown
(13) Other volcanic cloud information:Unknown
(14) Contacts:Chris Waythomas, Acting Scientist-in-Charge, USGS
chris@usgs.gov (907) 786-7497

Jeff Freymueller, Coordinating Scientist, UAFGI
jeff.freymueller@gi.alaska.edu (907) 378-7556
(15) Next Notice:A new VONA will be issued if conditions change significantly or alert levels are modified. While a VONA is in effect, regularly scheduled updates are posted at
http://www.avo.alaska.edu