CENAPRED reported that eruptive activity continued at Popocatépetl during 10-17 October. Long-period events totaling 87-402 per day were accompanied by steam-and-gas plumes that sometimes contained minor amounts of ash. Some of the plumes drifted NW and W, though cloudy weather conditions sometimes prevented visual observations. Periods of low-amplitude and high-frequency volcanic tremor were recorded daily, each lasting 23-462 minutes. According to the Washington VAAC, a large, discrete ash plume was identified in a satellite image at 1026 on 12 October rising to 6.7 km (22,000 ft) a.s.l. and drifting NE. A thermal anomaly was also visible. A minor explosion was recorded at 0405 on 13 October by the seismic network; the VAAC reported that an ash plume was seen in satellite and webcam images at 0421 drifting almost 30 km N at an altitude of 6.1 km (20,000 ft) a.s.l. A satellite image from 0101 on 14 October showed ash fanning out to the NW at 6.7 km a.s.l. and an image from 0701 showed a continuously emitted ash plume drifting WNW and NW at the same altitude; the VAAC noted that the webcam was not operational. CENAPRED stated that a moderate explosion was recorded at 1419 on 14 October. Video taken by observers and posted on social media showed a dark ash plume rising from the volcano. At 1831 on 14 October ash emissions were ongoing and visible in webcam and satellite images drifting WNW and NW according to the VAAC. At 0626 on 15 October an ash plume was visible in satellite and webcam images slowly drifting W at an altitude of 6.4 km (21,000 ft) a.s.l. The Alert Level remained at Yellow, Phase Two (the second level on a three-color scale) and the public was warned to stay 12 km away from the crater.

Geological Summary. Volcán Popocatépetl, whose name is the Aztec word for smoking mountain, rises 70 km SE of Mexico City to form North America's 2nd-highest volcano. The glacier-clad stratovolcano contains a steep-walled, 400 x 600 m wide crater. The generally symmetrical volcano is modified by the sharp-peaked Ventorrillo on the NW, a remnant of an earlier volcano. At least three previous major cones were destroyed by gravitational failure during the Pleistocene, producing massive debris-avalanche deposits covering broad areas to the south. The modern volcano was constructed south of the late-Pleistocene to Holocene El Fraile cone. Three major Plinian eruptions, the most recent of which took place about 800 CE, have occurred since the mid-Holocene, accompanied by pyroclastic flows and voluminous lahars that swept basins below the volcano. Frequent historical eruptions, first recorded in Aztec codices, have occurred since Pre-Columbian time.

Sources: Centro Nacional de Prevencion de Desastres (CENAPRED), El Informante