Mexico's El Popo volcano fills towns with ash

STORY: The National Coordination of Civil Protection reported through its Twitter account Thursday that due to a low amplitude tremor, the volcano maintains a continuous emission of water steam and gas with low ash content, reaching a height between 430-660 yards (400-600 meters) in a south-southeast direction.

Earlier this week, several towns closed schools due to the volcanic ash.

Popocatepetl, meaning "Smoking Hill" in the native Aztec language Nahuatl, is one of the world's most closely monitored volcanoes. It stands only about 45 miles (72 km) southeast of Mexico City.