Cascade Range Current Update |
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U.S. Geological Survey, Vancouver, Washington
University of Washington, Pacific Northwest Seismograph Network, Seattle, Washington
Thursday, January 6, 2005 9:25 a.m. PST (1725 UTC)
MOUNT ST. HELENS UPDATE
Current status is Volcano Advisory (Alert Level 2); aviation color code ORANGE Growth of the new lava dome inside the crater of Mount St. Helens continues, accompanied by low rates of seismicity, low emissions of steam and volcanic gases, and minor production of ash. During such eruptions, episodic changes in the level of activity can occur over days to months. The eruption could also intensify suddenly or with little warning and produce explosions that cause hazardous conditions within several miles of the crater and farther downwind. Small lahars could suddenly descend the Toutle River if triggered by heavy rain or by interaction of hot rocks with snow and ice. These lahars pose a negligible hazard below the Sediment Retention Structure (SRS) but could pose a hazard along the river channel upstream. Potential ash hazards:Wind forecasts from the National Oceanic and Atmospheric Administration (NOAA), coupled with eruption models, show that ash clouds that rise above the crater rim today would drift southward early in the day then switch to an eastward drift by late afternoon. Recent observations: The mountain is obscured by clouds from a storm that has settled into the region. Several inches of snow are expected to accumulate at the mountain over the next few days. Seismometers indicate that seismicity continues at a very low level, and the GPS unit on the rear of the lava dome continues to move slowly outward and downward. Crews will be back in the field during the next significant break in weather to install more GPS units.
For additional information, background, images, and other graphics: http://vulcan.wr.usgs.gov/News/framework.html
For seismic information: http://www.pnsn.org/HELENS/welcome.html
For a definition of alert levels: http://vulcan.wr.usgs.gov/News/framework.html
For a webcam view of the volcano: http://www.fs.fed.us/gpnf/volcanocams/msh/
Telephone recordings with the latest update on Mount St. Helens and phone contacts for additional information can be heard by calling:
Media (360) 891-5180
General public (360) 891-5202
OTHER CASCADE VOLCANOES
All other volcanoes in the Cascade Range are all at normal levels of background seismicity. These include Mount Baker, Glacier Peak, Mount Rainier, and Mount Adams in Washington State; Mount Hood, Mount Jefferson, Three Sisters, Newberry, and Crater Lake, in Oregon; and Medicine Lake, Mount Shasta, and Lassen Peak in northern California.
USGS Cascades Volcano Observatory, the Pacific Northwest Seismograph Network at the University of Washington, and the USGS Northern California Seismic Network and Volcano Hazards Team in Menlo Park, California, monitor the major volcanoes in the Cascade Range of northern California, Oregon, and Washington.
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