Wired said:The high alert at Mexicos Popocatépetl remains in place as the restless Mexican volcano still shows signs that new magma is at the surface, meaning a larger explosion could occur if pressures builds under the summit crater. Over the last day, the volcano has produced 22 separate explosions (see above) or exhalations of ash, as they are refered. The latest CENAPRED update from today (May 16) says that the explosive strombolian activity at the summit has continued, with blocks of volcanic tephra and ash being thrown up to 400 meters from the vent. Ash has been reported falling occasionally in cities all around the volcano as well. Combine that with near constant seismicity and ash emissions reaching up to 3.5 km (11,500 feet) that wax and wane, and we have a very active volcano. CENAPRED has left Popocatépetl at alert level Yellow Phase 3 and officials are making plans for evacuations and shelters if the eruption gets worse. The current 12 kilometer exclusion zone around the volcano also remains in place.
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