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April 1, 2006:
- 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, 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.
- Wind forecasts show that ash clouds that rise above the crater rim today would drift north-northwestward in the morning and eastward in the evening.
- 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.
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- Recent observations: No significant changes have been detected in the level of activity during the past day. Lingering clouds around the volcano prevent direct viewing of the lava dome. Although the overall level of seismicity remains low, the eruption of lava into the crater continues as evidenced by ongoing rockfall activity and continuous GPS measurements made on the growing lava lobe.
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April 2, 2006:
- 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.
- Wind forecasts show that ash clouds that rise above the crater rim today would drift northeastward.
- Recent observations: No significant changes have been detected in the level of activity during the past day. A slow-moving Pacific weather system will send clouds and precipitation over the volcano today and tomorrow, and offer little chance for direct observation of the crater area. Although the overall level of seismicity remains low, the eruption of lava into the crater continues as evidenced by ongoing rockfall activity and continuous GPS measurements made on the growing lava lobe.
April 3, 2006:
- 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.
- Wind forecasts show that any ash clouds that rise above the crater rim today would drift to the north or north-northwest.
- Recent observations: Clouds limited visual observation of the volcano this morning. This morning’s seismicity is quiet, with smaller earthquakes once every several minutes. One earthquake larger than magnitude 2 occurred this morning at 8:14 pm PDT. Periodic loss of seismic signals at some stations is probably the result of burial by snow.
April 4, 2006:
- 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.
- Wind forecasts show that any ash clouds that rise above the crater rim today would drift to the north.
- Recent observations: Mostly clear skies allow views of the snow-covered volcano this morning. Crews are in the field taking advantage of this break in the weather to repair monitoring instruments, measure emissions of volcanic gasses, conduct infrared imaging of the growing lava dome, and hopefully to restore some of the remote cameras. Seismicity is quiet, with smaller earthquakes once every several minutes, and GPS receivers show that solidified dacite lava continues to extrude slowly.
April 5, 2006:
- 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.
- Wind forecasts show that any ash clouds that rise above the crater rim today would drift to the north during the morning, shifting to the east/southeast in the afternoon.
- Recent observations: Field crews on Tuesday took advantage of a break in the weather to service some instruments and conduct infrared imaging of the growing lava dome. Seismicity is low, with small earthquakes once every several minutes, and GPS receivers show that solidified dacite lava continues to extrude slowly.
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.
April 6, 2006:
- 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.
- Wind forecasts show that any ash clouds that rise above the crater rim today would drift to the east-northeast this morning shifting to the northeast by afternoon.
- Recent observations: Views from the Johnston Ridge Observatory VolcanoCam this morning show low clouds obscuring the crater of the volcano. Seismicity is quiet, with only one earthquake greater than M2 recorded in the last 24 hours (yesterday at 4:06 PM PDT, 2306 UTC). Smaller “drumbeat” earthquakes are occurring once every several minutes. GPS receivers indicate that solidified dacite lava continues to extrude slowly.
April 7, 2006:
- 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.
- Wind forecasts show that any ash clouds that rise above the crater rim today would drift to the north.
- Recent observations: Partly cloudy skies afford views of the snow-covered volcano this morning. A light steam plume can be seen rising from the growing lava dome. Seismicity is quiet, with one earthquake greater than M2 recorded at 11:45 PM PDT (0645 UTC) and smaller “drumbeat” earthquakes occurring once every several minutes.
April 8, 2006:
- 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.
- Wind forecasts show that any ash clouds that rise above the crater rim today would drift west-northwestward in the morning and eastward in the evening.
- Recent observations : Partly cloudy skies obscure the volcano today. Seismicity is quiet, with smaller “drumbeat” earthquakes occurring once every several minutes.
April 9, 2006:
- 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.
- Wind forecasts show that any ash clouds that rise above the crater rim today would drift eastward in the morning and evening.
- Recent observations: Partly cloudy skies obscure the volcano today. Seismicity is quiet, with smaller ?drumbeat? earthquakes occurring once every several minutes.
April 10, 2006:
- 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.
- Wind forecasts show that any ash clouds that rise above the crater rim today would drift to the east during the morning, shifting to the north in the afternoon.
- Recent observations: The volcano is obscured by clouds this morning. The steam plume visible late Sunday afternoon reflected local meteorological conditions and not a change in volcanic activity.
April 11, 2006:
- 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.
- Wind forecasts show that any ash clouds that rise above the crater rim today would drift north to northeastward.
- Recent observations: Clouds partly obscure the volcano today although this morning the crater has been mostly clear. Although seismicity has been relatively quiet lately, recent observations of the dome indicate that an actively moving slab of solidified lava continues to extrude at a rate of about 2 meters per day, and a GPS unit on the western margin of the dome bounded by that slab continues to migrate westward at about a meter per day.
April 12, 2006:
- 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.
- Wind forecasts show that any ash clouds that rise above the crater rim today would drift north to northeastward early, and that high-elevation plumes would drift east-southeastward later in the day.
- Recent observations: This morning, the volcano is mostly obscured by clouds. Seismicity continues to be relatively quiet, although a moderate-sized earthquake punctuated the low-level background of small quakes last night at 7:42 p.m. GPS data show that a part of the active dome continues to move slowly westward at about a meter per day.
April 13, 2006:
- 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.
- Wind forecasts show that any ash clouds that rise above the crater rim today would drift northeastward, although early in the day at high-elevation they would drift broadly eastward.
- Recent observations: The volcano is clear this morning affording good views of the newly growing lava dome. The actively emerging slab of solidified lava can be seen as the highest hump on the left side of the snow-free mass. Seismicity continues to be relatively quiet, with a steady background of small quakes occasionally punctuated by a moderate-sized earthquake, such as at 11:49 p.m. yesterday and 7:40 a.m. today. GPS data show that a part of the active dome continues to move slowly westward at about a meter per day.
April 14, 2006:
- 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.
- Wind forecasts show that any ash clouds that rise above the crater rim today would drift northeastward.
- Recent observations: Clouds obscured visual observation of the volcano this morning. Heavy snow is forecast and storm related outages of one or more seismic stations are likely. The monitoring network is highly redundant and such outages will not significantly degrade detection of earthquakes. The eruption continues unabated as demonstrated by a steady background of small earthquakes and steady westward movement (about one meter per day) of a GPS station on the active dome.
April 15, 2006:
- 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.
- Wind forecasts show that any ash clouds that rise above the crater rim today would drift northeastward.
- Recent observations: Clouds obscured visual observation of the volcano again this morning. Heavy snow is forecast and storm related outages of one or more seismic stations are likely. The monitoring network is highly redundant and such outages will not significantly degrade detection of earthquakes. A steady background of small crater earthquakes and slow westward movement (about one meter per day) of a GPS station on the active dome indicate ongoing extrusion of solidified dacite lava.
April 16, 2006:
- 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.
- Wind forecasts show that any ash clouds that rise above the crater rim today would drift northeastward.
- Recent observations: Clouds obscured visual observation of the volcano again this morning. The eruption continues with no observable changes over the past few days. Seismicity is low and steady and a GPS station on the actively growing dome continues to move to the west at a rate of about one meter per day.
April 17, 2006:
- 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.
- Wind forecasts show that any ash clouds that rise above the crater rim today would drift east-northeastward at low elevations, and east to east-southeastward at high elevations.
- Recent observations: Clouds continue to obscure the mountain this morning. Heavy snowfall has blanketed the mountain and is causing episodic and temporary disruptions of transmitted seismic signals. The monitoring network is highly redundant, however, and such outages do not significantly degrade detection of earthquakes. The steady background of small crater earthquakes and slow westward movement (about one meter per day) of a GPS station on the active dome continue, and indicate ongoing extrusion of solidified lava.
April 18, 2006:
- 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.
- Wind forecasts show that any ash clouds that rise above the crater rim early today would drift northeastward at low elevations, and east-southeastward at high elevations. Later in the day ash would drift east-southeastward at low elevations, and southeastward at high elevations.
- Recent observations: It is sunny and clear today at the mountain and partly sunny conditions are expected for the remainder, allowing visual observations from the ground and air. Monitoring instruments show no significant change in patterns of earthquake activity or deformation. Seismicity continues as very small periodic earthquakes, recurring every few minutes, punctuated by occasional larger but still small events. The larger earthquakes are typically less than M3 and occur at an average rate of less than 1 per day. The active dome is building with motion to the west at about 1 meter per day, consistent with the trend established over the last two months. Monitoring data are within the range of typical recent values.
April 19, 2006:
- 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.
- Wind forecasts show that any ash clouds that rise above the crater rim today would drift to the northeast.
- Recent observations: Again it is sunny and clear today at the mountain. Partly sunny conditions are expected for the remainder day, allowing visual observations from the ground and air. Seismicity continues as very small periodic earthquakes, recurring every few minutes, punctuated by occasional larger but still small events. The large earthquakes are typically less than M3 and occur at a rate of less than 1 per day; there have been none of these in the last 24 hours. The active dome continues to build with motion to the west at about 1 meter per day, consistent with the trend established over the last two months. Monitoring instruments show no significant change in patterns of earthquake activity or deformation.
April 20, 2006:
- 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.
- Wind forecasts show that any ash clouds that rise above the crater rim today would drift to the northeast.
- Recent observations: Partly cloudy conditions prevail this morning, but the mountain is visible from the Johnston Ridge Observatory. Similar conditions are expected for the remainder of the day. Seismicity continues as very small periodic earthquakes, recurring every few minutes, punctuated by occasional larger but still small events. The large earthquakes are typically less than M3 and occur at an average rate of less than 1 per day. The active dome continues to build with motion to the west. Monitoring instruments show no significant change in patterns of earthquake activity or deformation from those established over the past few months.
April 21, 2006:
- 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.
- Wind forecasts show that any ash clouds that rise above the crater rim early in the day would drift to the northeast. Later in the day ash would drift to the south and east.
- Recent observations: Cloudy conditions with showers prevail this morning and rain is expected to continue into the afternoon. Seismicity continues as very small periodic earthquakes, recurring every few minutes, punctuated by occasional larger but still small events. The larger earthquakes are typically less than M3, e.g., a M2.7 at 12:28 PDT yesterday afternoon. The active dome continues to build with motion to the west. Monitoring instruments show no significant change in patterns of earthquake activity or deformation from those established over the past few months.
April 22, 2006:
- 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.
- Wind forecasts show that any ash clouds that rise above the crater rim today would drift to the south.
- Recent observations: It is a sunny and clear morning at the volcano and is expected to remain so throughout the day. The eruption continues unabated and without significant changes. As indicated by seismic and GPS instruments located in and around the crater, the new dome continues to grow in a westward direction at less than a meter per day to a drumbeat of very small earthquakes.
April 23, 2006:
- 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.
- Wind forecasts show that any ash clouds that rise above the crater rim today would drift to the southwest.
- Recent observations: It is a beautiful spring day in southwest Washington and Mt. Saint Helens is clearly visible in all its glory. Real-time seismic and ground deformation instruments located in the crater and around the mountain indicate that new dome growth has continued over the last 24 hours in a relatively quiet and uneventful fashion, with frequent very small earthquakes and slow but steady westward expansion of the extrusion at approximately 1 meter per day.
April 24, 2006:
- 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.
- Wind forecasts show that any ash clouds that rise above the crater rim today would drift to the west and southwest.
- Recent observations: Clear and sunny conditions prevail at the mountain again this morning, with some cloud cover expected later in the day. The eruption conditions remain unchanged as the slow but steady growth of the new dome is heralded by the drumbeat of small shallow earthquakes in the crater, interposed with occasional rock falls from the over-steepened and decrepitating extrusive mass.
April 25, 2006:
- 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.
- Wind forecasts show that any ash clouds that rise above the crater rim today would drift principally to the east.
- Recent observations: The volcano rim and crater are clearly visible from Johnston Ridge despite the deck of clouds enveloping part of the region this morning. Eruptive behavior remains quiescent and unchanged, as the extruding new dome continues to creep westward about one meter per day. Very small earthquakes continue to occur about once each several minutes. A single large earthquake (estimated magnitude 3.3) occurred at about 11:30 PDT last night, but it had no noticeable effect on eruptive behavior.
April 26, 2006:
- 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.
- Wind forecasts show that any ash clouds that rise above the crater rim today would drift principally to the east and southeast.
- Recent observations: The volcano rim and crater are intermittently visible from Johnston Ridge despite the deck of clouds enveloping most of western Washington this morning. Eruptive behavior remains unchanged, and the extruding new dome continues its steady westward march at a rate of about one meter per day. Very small earthquakes continue to occur roughly once each several minutes.
April 27, 2006:
- 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.
- Wind forecasts show that any ash clouds that rise above the crater rim today would drift principally to the east and southeast.
- Recent observations: Skies around the volcano are mostly clear this morning, and atmospheric conditions are favorable for vapor condensation and formation of a visible plume rising from the new dome and perhaps above the crater rim. The volcano’s eruptive behavior remains quiescent and unchanged. The extruding new dome continues to move westward at a rate of about one meter per day, and very small earthquakes continue to occur roughly once each several minutes. Field crews plan to perform maintenance on camera and instrument sites today.
April 28, 2006:
- 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.
- Wind forecasts show that any ash clouds that rise above the crater rim today would drift principally to the east and northeast.
- Recent observations: Clear skies again prevail around the volcano this morning. The National Weather Service forecast indicates that fair weather should continue throughout most of the day, with light winds and high freezing levels. The volcano’s eruptive behavior remains quiescent and unchanged. The extruding new dome continues to move westward at a rate of about one meter per day, and very small earthquakes continue to occur roughly once each several minutes.
April 29, 2006:
- 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.
- Wind forecasts show that any ash clouds that rise above the crater rim today would drift principally to the northeast and east.
- Recent observations: The volcano is clearly visible from Johnston Ridge this morning, but a thickening cloud cover threatens to obscure the view later in the day. The volcano’s eruptive behavior remains quiescent and unchanged. The extruding new dome continues to advance westward at a rate of about one meter per day, and very small earthquakes continue to occur roughly once each several minutes. Field crews took advantage of yesterday’s fine weather to resuscitate ailing cameras and instruments and to observe and photograph the new dome. The most active part of the dome (called spine 7) appears to have grown in height and steepness since the last close-up observations were made on April 4, although this interpretation is preliminary, and photogrammetric analysis will be required to confirm it.
April 30, 2006:
- 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.
- Wind forecasts show that any ash clouds that rise above the crater rim today would drift principally to the east and southeast.
- Recent observations: Partly cloudy skies prevail in the region this morning. The volcano has been mostly visible from Johnston Ridge, although low clouds and fog have intermittently obscured the view. Eruptive behavior remains quiescent and unchanged. The extruding new dome continues to advance westward at a rate of about one meter per day, and very small earthquakes continue to occur roughly once each several minutes.
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