Tag Archives: Mount St. Helens

On 10 July, CVO lowered the Volcano Alert Level for Mount St. Helens to Normal and the Aviation Color Code to Green, following the cessation of lava-dome growth in late January and about five months with no signs of renewed … Continue reading →

On 21 February, CVO lowered the Alert Level for Mount St. Helens from Watch to Advisory and the Aviation Color Code from Orange to Yellow. Comparison of photographs taken by remote cameras during late January to mid-February 2008 showed no … Continue reading →

Data from deformation-monitoring instruments indicated that during13-19 February lava-dome growth at Mount St. Helens continued. Seismicity persisted at low levels, punctuated by M 1.5-2.5, and occasionally larger, earthquakes. Clouds and snow cover frequently inhibited visual observations. Source: Cascades Volcano Observatory … Continue reading →

Data from deformation-monitoring instruments indicated that during 6-12 February lava-dome growth at Mount St. Helens continued. Seismicity persisted at low levels, punctuated by M 1.5-2.5, and occasionally larger, earthquakes. Clouds and snow cover frequently inhibited visual observations. Source: Cascades Volcano … Continue reading →

Data from deformation-monitoring instruments indicated that during 2-8 January lava-dome growth at Mount St. Helens continued. Seismicity persisted at low levels, punctuated by M 1.5-2.5, and occasionally larger, earthquakes. A new small spine was seen on top of the active … Continue reading →

Data from deformation-monitoring instruments indicated that during 26 December-1 January lava-dome growth at Mount St. Helens continued. Seismicity persisted at low levels, punctuated by M 1.5-2.5, and occasionally larger, earthquakes. Clouds occasionally inhibited visual observations. Source: Cascades Volcano Observatory – … Continue reading →

Data from deformation-monitoring instruments indicated that during 19-25 December lava-dome growth at Mount St. Helens continued. Seismicity persisted at low levels, punctuated by M 1.5-2.5, and occasionally larger, earthquakes. Clouds occasionally inhibited visual observations. Source: Cascades Volcano Observatory – “Reports … Continue reading →

 Data from deformation-monitoring instruments indicated that during 5-11 December lava-dome growth at Mount St. Helens continued. Based on interpretations of flow-monitoring system data, lahars flowed out of the crater on 4 December, after a weather system passed through the region. … Continue reading →

Data from deformation-monitoring instruments indicated that during 28 November-4 December lava-dome growth at Mount St. Helens continued. Small inflation-deflation events occurred which were interpreted as dome-growth pulses. Seismicity persisted at low levels, punctuated by M 1.5-2.5, and occasionally larger, earthquakes. … Continue reading →