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June 1, 2005:
- 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 southeastward to east-southeastward.
- 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: Clouds continue to obscure views of the lava dome, but there have been no significant changes in rates of seismicity or ground deformation during the past few days. We want to correct an error in yesterday’s update. The GPS unit on the older part of the new dome near the vent continues to move northward (not southward as stated yesterday) at slightly more than 6 inches per day, eastward at about 18 inches per day, and to rise vertically a few inches per day.
- *** This line included in daily update but excluded for rest of month on this page.
June 2, 2005:
- 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 south-southwestward early in the day and south-southeastward later.
- Recent observations: Clouds continue to obscure views of the lava dome, but there have been no significant changes in rates of seismicity or ground deformation during the past few days. Images from the camera at the mouth of the crater show that the lava spine at the northwest end of the new dome continues to grow even as parts of it continue to crumble. When the weather improves, field crews plan to make measurements of gas and other observations.
June 3, 2005:
- 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 southeastward.
- Recent observations: A low layer of clouds obscures views of the lava dome in the JRO VolcanoCam, but images from the camera at the mouth of the crater show that the crater is clear and that the lava spine at the northwest end of the new dome continues to grow. Seismicity and deformation detected by GPS units have not changed significantly over the past few days. If the cloud layer breaks today, field crews will attempt to make measurements of gas and other observations.
June 4, 2005:
- 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 early in the day and northeastward later.
- Recent observations: A low layer of clouds obscures views of the lava dome in both the JRO VolcanoCam and the USGS DomeCam. Seismicity remains unchanged over the past few days, but the rate of motion of a GPS unit on the north end of the new dome has slowed slightly; it continues to creep eastward and northward at a rate of several inches per day, but it is no longer rising vertically. The lava spine, however, continues to grow. Yesterday, clouds prevented a field crew from making measurements of gases. If the cloud layer breaks sufficiently today, that crew may try again to make the measurements.
June 5, 2005:
- 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-northeastward to northeastward early in the day and northeastward later.
- Recent observations: Poor weather conditions foiled yesterday’s attempt to conduct a field experiment that involves comparing our traditional airborne techniques and a newly developed ground-based technique to measure gas emissions from the growing lava dome. A scientist from USGS Hawaiian Volcano Observatory, who is an expert in the new technique, and our CVO gas specialists will hopefully get a chance in the coming week to perform the experiment.
June 6, 2005:
- 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-northeastward early in the day and eastward to southeastward later.
- Recent observations: Seismic and deformation data continue trends of the past few weeks. Earthquakes of about magnitude 1 are occurring approximately every 5 minutes. The weather outlook is poor for field work this week.
June 7, 2005:
- 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 westward early in the day. Later in the day, lower altitude clouds would drift east-southeastward and higher altitude clouds would drift southward.
- Recent observations: The volcano is once again obscured by clouds. Seismic and deformation data continue trends of the past few weeks, from which we infer continued lava-dome growth. We’re hoping that conditions will improve on Thursday and permit field observations and a gas-sensing experiment.
June 8, 2005:
- 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 southeastward.
- Recent observations: The volcano is once again obscured by clouds this morning. Seismic and deformation data continue trends of the past few weeks, from which we infer continued lava-dome growth. Crews are out today working on repairs to our radio communications system and installing new seismometers around the mountain.
June 9, 2005:
- 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 south-southeastward early in the day and shift to a more east-southeastward trajectory later.
- Recent observations: The volcano is clear today and field crews are taking advantage of the opportunity to obtain gas measurements, make observations, and service various instrumentation sites. Overall, the volcano remains in a relatively quiet state. Seismic and deformation data continue trends of the past few weeks, namely small earthquakes about every five minutes, little to no movement of the old lava dome, minor movement of the north end of the new dome, and continued growth of the lava spine.
June 10, 2005:
- 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.
- Recent observations: Yesterday’s gas-sensing experiment was partly successful. After scientists spent two hours hauling equipment and setting it up on the east crater rim in clear conditions, the crater clouded in and remained so for much of the day. Scientists were able to get only one preliminary set of data with the new infrared spectrometer. The results were encouraging and showed that the technique will work, but they weren’t sufficient to provide quantitative measurement of gases. The instrument has to go back to our Hawaiian Volcano Observatory for awhile, but we will retry the experiment later in the summer. Concurrent measurements of gases using our usual airborne techniques were likewise foiled by weather. Good photographs of the new lava dome taken yesterday morning will be available on our web site today.
June 11, 2005:
- 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 to east-southeastward.
- Recent observations: Clouds have prevented any views of the crater since Thursday, but seismic data suggest there has been no change in level of activity. GPS instruments near the new lava dome have stopped moving during the past few days as has one on a relatively inactive part of the new dome. Similar changes have occurred during the past few months, and typically have been followed by a change in the sense of movement.
June 12, 2005:
- 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-southeastward.
- Recent observations: Clouds continue to obscure the crater. Seismic data suggest there has been no change in level of activity, and GPS instruments on and near the new lava dome have shown little movement during the past few days. Views of the crater last Thursday, however, indicated that the spine of lava near the north end of the new dome continues to grow.
June 13, 2005:
- 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 to east-northeastward.
- Recent observations: There have been no significant changes in seismicity or other monitored activity during the past day. The crater remains obscured by clouds.
June 14, 2005:
- 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 to east-northeastward.
- Recent observations: The volcano is mostly clouded this morning, but the clouds part sporadically allowing glimpses into the crater. There have been no significant changes in seismicity or other monitored activity during the past day, and no significant changes to the shape of the spine of lava since last week.
June 15, 2005:
- 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 to northeastward.
- Recent observations: Today’s surprisingly good weather should allow a variety of field activities. Thermal-imaging observations are currently underway. Work will continue on installation of several broad-band seismometers; part of a large array that will operate through the summer and provide information about the character of the volcano’s deep magmatic system. Several photographic missions are planned along with some close aerial examination of the internal structure of the new lava dome, which has been revealed by crumbling of its west margin. Last evening’s M=7.2 earthquake off the northern California coast shows up well on most of the St. Helens’ webicorder plots, but it is barely visible on station SEP (Old Dome). That is because the type of seismometer at SEP doesn’t respond well to the low-frequency seismic waves from distant earthquakes. This large earthquake does not appear to have triggered seismicity at any Cascade volcano.
June 16, 2005:
- 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 northward. Under these conditions, Johnston Ridge and the east end of Highway 504 could receive ash fall.
- Recent observations: Yesterday’s good weather allowed a variety of field activities to occur. Crews conducted thermal-imaging and visual observations, obtained new photographs, and continued installing broad-band seismometers as part of an array that will operate through the summer to provide information about the character of the volcano’s deep magmatic system. Observations reveal that the lava spine continues to grow and that temperatures in cracks near the base of the spine are near 700 degrees C (1300 degrees F).
June 17, 2005:
- 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-northwestward to northward. Under these conditions, Johnston Ridge and the east end of Highway 504 could receive ash fall.
- Recent observations: Additional analysis of data from Wednesday’s field work shows an interesting pattern. Thermal-sensing data reveal a hot zone around the perimeter of the western part of the new lava dome, an area about 400 meters long by 50 meters wide. In the past few months, such a hot zone has been restricted to the north end of the dome, where lava was being extruded to form a succession of whaleback-shaped domes, which chiefly moved southward. Coupled with the orientation of grooves that form as the dome extrudes from the vent, these new thermal data suggest that much of the western part of the dome is moving upward, as well as southward. We would like to place a GPS spider on this part of the dome to measure its rate of movement, but stable spots are scarce because this part of the dome is also producing a lot of rockfalls.
June 18, 2005:
- 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-northwestward to northward. Under these conditions, Johnston Ridge and the east end of Highway 504 could receive ash fall.
- Recent observations: Clouds obscure the crater this morning. Although seismicity remains unchanged over the past several days and GPS units on the older part of the new dome show little movement, thermal observations and images from a camera at the mouth of the crater show that the western end of the dome continues to grow.
June 19, 2005:
- 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 westward, but with enough variation that Johnston Ridge and parts of Highway 504 could receive ash fall.
- Recent observations: The nice vapor plume that was visible earlier this morning has now dissipated and the new lava dome and crater are clear. There has been no change in the level of activity from that of the past few weeks. Early morning and evening atmospheric conditions have been favorable for production of visible vapor plumes, so we may see one later this afternoon and evening.
June 20, 2005:
- 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 westward to northwestward early in the day, but shift to northward to north-northeastward trajectories as the day progresses. Thus, Johnston Ridge and parts of Highway 504 could receive ash fall.
- Recent observations: A clear day today should offer good views of the new dome and perhaps a vapor plume if conditions are right. There has been no change in the level of activity from that of the past few weeks. Weather permitting, crews will try to get out later this week to continue observations, to conduct surveys of targets on the dome to monitor movement, and perhaps to place new GPS instrumentation units.
June 21, 2005:
- 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-northwestward to northward early in the day and north-northeastward later. Thus, Johnston Ridge and parts of Highway 504 could receive ash fall.
- Recent observations: Crews are in the field today to survey features and targets on the lava dome from the crater mouth and rim, to continue installation of an array of broad-band seismometers, and to examine the glacier for potential sites for GPS spiders. Several episodes of bright glow were picked up on the USFS VolcanoCam last night and observers reported numerous incandescent rockfalls from the west flank of the lava dome. Highly fractured lava on the west flank of the dome, just south of the smooth whaleback, is susceptible to such rockfalls.
June 22, 2005:
- 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 early in the day and eastward later. Johnston Ridge and Highway 504 should generally be spared of any ash fall under these conditions.
- Recent observations: The crater is obscured by clouds this morning and may remain so for the day. Yesterday crews surveyed features and targets on the lava dome from the crater mouth and rim, installed additional broad-band seismometers, and examined the glacier and dome for potential sites for GPS spiders. Observations reveal that the smooth lava spine continues to grow and has increased in height by many meters in just the past few days. It is now as tall as or taller than it has ever been. In the coming days and weeks rockfalls are likely to occur.
June 23, 2005:
- 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 southeastward. Johnston Ridge and Highway 504 would not receive any ash fall under these conditions.
- Recent observations: The crater is clear today, and when low clouds dissipate the view from JRO should be excellent. Analyses of images from the USGS camera at the crater mouth reveal that the smooth lava spine continues to grow. The spine is presently about 160 m (525 ft) tall from ground level to its top, and it stands about 180 m (600 ft) higher than the old lava dome. It is now taller than it has ever been. In the coming days and weeks rockfalls are likely to occur.
June 24, 2005:
- 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 to east-southeastward.
- Recent observations: Analysis of images from the camera at Sugar Bowl, near the mouth of the crater, show that the smooth lava spine at the north end of the new lava dome continues to emerge from the vent at a rate of about 6 to 12 feet per day. Rockfalls from the top of the spine keep its height from increasing by that same rate, but the spine is continuing to get higher.
June 25, 2005:
- 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 to east-southeastward.
- Recent observations: The crater and growing lava dome are clear this morning above the low clouds that are covering the lowlands. As is typical on many mornings, a small vapor plume is rising from the north end of the dome. No significant changes have occurred recently in patterns of seismicity and ground deformation that are accompanying dome extrusion. Some Portland residents felt this morning’s magnitude 2.7 earthquake that was centered near Laurelhurst Park. For comparison, that earthquake was much larger and much deeper (9 miles) than the several hundred earthquakes that occur each day in Mount St. Helens’ crater (mostly less than magnitude 2 and less than 1 mile deep).
June 26, 2005:
- 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 chiefly eastward, but any ash clouds that reach high altitude early in the day would drift south-southeastward.
- Recent observations: We had a brief glimpse of the crater and growing lava dome this morning from our camera near the crater mouth. There were no significant changes visible on the image. Seismic and geodetic data remain in the typical patterns established during the past months of dome growth.
June 27, 2005:
- 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 to southeastward.
- Recent observations: The volcano is obscured by clouds, but seismic and deformation data continue trends of the past few weeks. A problem with an Internet server in the USGS web system denied access to the CVO web site over the weekend (including from CVO!). That problem has now been fixed. The Saturday and Sunday updates will be available in the Past Updates section of the web site as soon as possible.
June 28, 2005:
- 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 south-southeastward.
- Recent observations: The crater is partly cloudy this morning and views of the dome are obscured. Seismic and deformation data continue trends of the past few weeks. Later this week when weather improves, crews plan to install and retrieve instrumentation packages in the crater, reoccupy GPS stations on the volcano’s flanks, collect water samples, and service flow-warning instrumentation at the mouth of the crater.
June 29, 2005:
- 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 south-southeastward early and broadly southward to eastward later.
- Recent observations: The crater is clear this morning, and images from the USGS camera at the crater mouth show that the dome continues to grow. Seismic and deformation data continue trends of the past few weeks. Tomorrow if the weather cooperates, field crews plan to install and retrieve instrumentation packages in the crater, conduct GPS surveys on the volcano’s flanks, collect water samples, and service flow-warning instrumentation at the mouth of the crater.
June 30, 2005:
- 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 to east-northeastward.
- Recent observations: The crater is basking in sun and field crews are out early to start an ambitious day. They will retrieve GPS and seismic spiders that need repair or a battery change and install new spiders. They’ll also set out GPS instruments to reoccupy some survey points on the volcano’s flanks, collect water samples, and service flow-warning instrumentation at the mouth of the crater. The last of 18 broadband seismometers that are being deployed for several months will be installed on the crater floor north of the 1980-86 lava dome. There have been no recent changes in the level of activity.
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