Cascade Range Current Updates
May 2010

CASCADE RANGE VOLCANO
Current Volcano Alert Level: NORMAL
Current Aviation Color Code: GREEN

Activity Update: All volcanoes in the Cascade Range are at normal levels of background seismicity. These include Mount Baker, Glacier Peak, Mount Rainier, Mount St. Helens, and Mount Adams in Washington State; Mount Hood, Mount Jefferson, Three Sisters, Newberry Volcano, and Crater Lake, in Oregon; and Medicine Lake volcano, Mount Shasta, and Lassen Peak in northern California. Mount St. Helens has been at Volcano Alert Level NORMAL (Aviation Color Code GREEN) since July 10, 2008.

Recent Observations: Activity at Cascade volcanoes remained at background levels this week. Small swarms of earthquakes were recorded at Lassen Peak and Mount Rainier. At Lassen, there was a short burst of activity on May 1. The largest earthquake in the swarm was magnitude 2.7. Several small earthquakes occurred beneath Mount Rainier this week, including a small flurry overnight (May 6-7). The largest event was magnitude 1.5. Seismicity at both volcanoes has since declined. Swarms such as these are normal at these volcanoes and not cause for concern. Preparations are in full swing for an Open House at the USGS Cascades Volcano Observatory tomorrow (May 8) and for other activities planned to commemorate the 30th anniversary of the May 18, 1980, eruption of Mount St. Helens.

CASCADE RANGE VOLCANO
Current Volcano Alert Level: NORMAL
Current Aviation Color Code: GREEN

Activity Update: All volcanoes in the Cascade Range are at normal levels of background seismicity. These include Mount Baker, Glacier Peak, Mount Rainier, Mount St. Helens, and Mount Adams in Washington State; Mount Hood, Mount Jefferson, Three Sisters, Newberry Volcano, and Crater Lake, in Oregon; and Medicine Lake volcano, Mount Shasta, and Lassen Peak in northern California. Mount St. Helens has been at Volcano Alert Level NORMAL (Aviation Color Code GREEN) since July 10, 2008.

Recent Observations: A minor swarm of about two dozen earthquakes that began around March 21 has continued this week. The largest earthquake, a magnitude 2.4, occurred at 10:09 PDT this morning. These events are not thought to be of volcanic origin. Mount Hood produces small swarms of this size once every few years.

Activity at other Cascade volcanoes remained at background levels this week.

CASCADE RANGE VOLCANO
Current Volcano Alert Level: NORMAL
Current Aviation Color Code: GREEN

Activity Update: All volcanoes in the Cascade Range are at normal levels of background seismicity. These include Mount Baker, Glacier Peak, Mount Rainier, Mount St. Helens, and Mount Adams in Washington State; Mount Hood, Mount Jefferson, Three Sisters, Newberry Volcano, and Crater Lake, in Oregon; and Medicine Lake volcano, Mount Shasta, and Lassen Peak in northern California. Mount St. Helens has been at Volcano Alert Level NORMAL (Aviation Color Code GREEN) since July 10, 2008.

Recent Observations: The recent (since March 21) swarm of minor earthquakes near Mount Hood has abated, although we cannot rule out a recurrence. These events are not thought to be of volcanic origin. Mount Hood produces small swarms of this size once every few years.

Activity at other Cascade volcanoes remained at background levels this week.

CASCADE RANGE VOLCANO
Current Volcano Alert Level: NORMAL
Current Aviation Color Code: GREEN

Activity Update: All volcanoes in the Cascade Range are at normal levels of background seismicity. These include Mount Baker, Glacier Peak, Mount Rainier, Mount St. Helens, and Mount Adams in Washington State; Mount Hood, Mount Jefferson, Three Sisters, Newberry Volcano, and Crater Lake, in Oregon; and Medicine Lake volcano, Mount Shasta, and Lassen Peak in northern California. Mount St. Helens has been at Volcano Alert Level NORMAL (Aviation Color Code GREEN) since July 10, 2008.

Recent Observations: Seismic activity and ground deformation at Cascade Range volcanoes have remained at background levels this week.