We know that Mount St. Helens is the volcano in the Cascades most likely to erupt again in our lifetimes. It is likely that the types, frequencies, and magnitudes of past activity will be repeated in the future. However, neither a large debris avalanche nor a major lateral blast like those of May 18, 1980 is likely now that a deep crater has formed.
The exact timing and magnitude of the next eruption cannot be forecast decades in advance, but an actively growing scientific knowledgebase and continued monitoring will enable the USGS to provide short- term forecasts and warnings in advance, as in 1980 and 2004.
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