Don't Freak Out About the Plume Over Mount St. Helens

A towering plume seen Tuesday over Mount St. Helens sparked brief concern that the volcano was erupting again, but the US Geological Survey and National Weather Service in Portland, Oregon, say that's not the case, per CBS News. "Good. Not prepared for that again," one X user responded. Instead, strong easterly winds kicked up ash left over from the volcano's historic 1980 eruption, the most destructive in modern US history, sending it thousands of feet above the crater and slopes, according to officials. Both the volcano alert level and the aviation color code remain at green, indicating normal conditions, per CNN. The phenomenon of resuspended ash isn't unusual for the area, especially when dry weather and high winds coincide.

Images from the USGS and the National Weather Service in Portland showed the ash drifting downwind. The plume was visible on satellite, and pilots reported ash as high as 10,000 feet. Tuesday's winds stemmed from a lingering ridge of high pressure that triggered strong, dry east winds and unleashed record September temperatures on Washington and Oregon. Although resuspended ash generally isn't dangerous, it can reduce visibility, affect air quality, and pose risks to aircraft engines, CNN notes. The agency expects the plume to dissipate once the winds subside.