Subject: Cleveland Volcano Activity Notice 20180822_1145
AVO/USGS Volcanic Activity Notice
Volcano: Cleveland (VNUM #311240)
Current Volcano Alert Level: ADVISORY
Previous Volcano Alert Level: WATCH
Current Aviation Color Code: YELLOW
Previous Aviation Color Code: ORANGE
Issued: Wednesday, August 22, 2018, 11:45 AM AKDT
Source: Alaska Volcano Observatory
Location: N 52 deg 49 min W 169 deg 56 min
Elevation: 5676 ft (1730 m)
Volcanic Activity Summary: The Aviation Color Code is being reduced to Yellow and the Volcano Alert Level to Advisory at Cleveland volcano. Minor explosive activity was last observed in late July and since that time there has been no evidence of lava extrusion in the summit crater. Elevated surface temperatures in the summit crater continue to be observed during periods of clear weather, but are interpreted to be due to hot degassing. This is typical of Cleveland volcano and indicates that low-level unrest continues.
Occasional, short duration explosive activity with minimal to no precursory signals is common at Cleveland volcano, and explosions may occur without warning. Explosions typically produce relatively small volcanic ash clouds that dissipate within hours; however, more significant ash emissions may occur as they have in the past.
Cleveland volcano is monitored by only two seismic stations, which restricts AVO’s ability to detect precursory unrest that may lead to an explosive eruption. Rapid detection of an ash-producing eruption may be possible using a combination of seismic, infrasound, lightning, and satellite data.
[Volcanic cloud height] None
[Other volcanic cloud information] n/a
Contacts: Michelle Coombs, Scientist-in-Charge, USGS
mcoombs (907) 786-7497
Jessica Larsen, Acting Coordinating Scientist, UAF
jflarsen (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.