Mexico's Popocatepetl volcano, also known as El Popo, has rumbled to life once again, this time spewing ash as high as three miles into the air. As we reported previously, the volcano put locals on alert in late August, when an earthquake triggered a series of 78 low-intensity exhalations. This time, the explosion reached more than 5 kilometers (about 3.1 miles) above the volcano's crater, according to Nature World News. It was reported that in 24 hours, from Nov 26-27, El Popo surprised locals with 129 incidents of ash columns, three more major explosions, and a 1.8 magnitude tremor. Mexico's Director of Civil Protection, Luis Felipe Puente, told the news source that the explosion consisted of steam, gas, and ash. Local authorities warned both locals and tourists to stay away from the areas near the volcano, particularly its crater, with hiking strongly prohibited. Ash in the air can cause breathing issues, especially for children, elderly, and pre-existing respiratory problems, so those in the area have been warned to use caution. While ash has also been an issue for transport in the past, most recently shutting down the Mexico City airport last spring when the same volcano had an eruption reaching a little over the height of this one, there have not been any reports that air traffic in the area has been canceled.