Mount St. Helens National Volcanic Monument

Climbing Mount St. Helens

Active Volcano Hazards

(USGS Photo - Aerial view Mount St. Helens eruption - October 1, 2004. )

For updated information on volcanic activity, please see:

USGS - Mount St. Helens Weekly Update

[Updated: February 22, 2008]

Geologists report that the dome building eruption that has been underway for more than three years at Mount St. Helens has stopped. During a period of dome growth in the 1980's such pauses in eruptive activity sometimes lasted for several weeks to almost a year. Geologists caution the new lava dome remains hot in some places and that the potential for localized hot avalanches or small steam explosions remains. Climbers and other winter recreationists should be aware that small steam explosions can occur without warning at any time. Although the impacts of such events are likely to be confined to the crater, it is important for potential climbers to understand they may be exposing themselves to volcanic hazards which cannot be forecast. Please review Active Volcano Hazards and other Climbing Safety information (links at right).   Detailed information and FAQs about the ongoing eruption are available by visiting the USGS Cascades Volcano Observatory website.  

Volcanic hazards may include:

• Ashfall. Explosions and lava dome rock fall can produce plumes of volcanic ash (gritty dust) that rise above the crater rim and drift downwind. Volcanic ash can cause discomfort to your nose, mouth and lungs and make breathing difficult. Ash can decrease visibility and traction, making travel hazardous.
• Ballistics (rock hurled onto the flanks of the volcano). Explosions in the crater may throw rock fragments above the crater rim. In rare instances, rocks may be large enough to cause injury or death.
• Volcanic gases. Under normal conditions, climbers may detect the faint odor of sulfur dioxide (lit match) and hydrogen sulfide (rotten eggs). Under rare circumstances, climbers may experience irritation to their nose, mouth and lungs.
• Debris Flows. Rain storms and melting snow can trigger small debris flows in gullies and stream channels on the volcano.

What to do if you encounter Volcanic Hazards?

Do not panic.

• If you encounter ashfall or ballistics, seek cover and act quickly to protect your head, airway and eyes.
• Descend rapidly to below the crater rim and seek cover behind boulders or slope breaks. Protect your head with a helmet or hard hat.
• Cover your nose and mouth with a dust mask.
• If you do not have recommended safety equipment, you can gain some protection by covering your head with your backpack and your face with a cloth. Remain in a protected position until the event subsides and hazards from falling rock and ash have subsided or ended (usually less than 30 minutes).

If volcanic activity increases or if hazards on the climbing routes are forecast, climbing access will be suspended and $15 permit fee will be refunded.  The $7 per permit service charge is non-refundable.

US Forest Service
Gifford Pinchot National Forest - Vancouver, WA
Mount St. Helens National Volcanic Monument - Amboy, WA
Last Modified: Monday, 25 February 2008 at 17:29:37 EST