Cascade Range Current Update |
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U.S. Geological Survey, Vancouver, Washington
University of Washington, Pacific Northwest Seismograph Network, Seattle, Washington
MOUNT ST. HELENS UPDATE
Current Volcano Alert Level WATCH ; 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,
changes in the level of activity can occur over days to months. The
eruption could 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 any ash clouds rising above the crater rim today would drift east-northeast.
Potential ash hazards to aviation: Under current eruptive conditions,
small, short-lived explosions may produce ash clouds that exceed 30,000
feet in altitude. Ash from such events can travel 100 miles or more
downwind.
Recent observations: Clouds and rain cloak the mountain today generally
obscuring views. Fleeting glimpses into the crater may be possible as
passing bands of precipitation clear the area. Inclement weather is
expected to continue through tomorrow. No significant changes in
monitored parameters have been observed in the last 24 hours. The
eruption continues unchanged in style or severity.
The U.S. Geological Survey and the University of Washington continue
to monitor the situation closely and will issue additional updates
and changes in alert level as warranted.
For additional information, background, images, and other
graphics:
For seismic information:
For a definition of alert levels:
For a webcam view of the volcano:
Telephone recordings with the latest update on Mount St. Helens
and phone contacts for additional information can be heard by
calling:
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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Link to:
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[University of Washington's Pacific Northwest Earthquake Information (current seismicity)]
