Alert level is raised in Central Mexico as volcano spews smoke and ash

An alert level was raised on Sunday for a volcano in central Mexico spewing ash and smoke, prompting officials to close schools and public parks and prepare for the possibility of evacuations.

The National Center for Disaster Prevention of Mexico said on Sunday that the alert level was raised to what is known as Phase 3just shy of an evacuation order, for the area around the Popocatépetl volcano, in the central region of the country.

Laura Velázquez Alzúa, the head of the center, said at one press conference on Sunday that when an alert level is raised to stage 3, it is possible for a volcano to create mild to moderate explosions that can hurl rock fragments, drop ash into surrounding areas, and disrupt air travel. The expulsion of magma is also possible, the center said.

President Andrés Manuel López Obrador of Mexico said on a press conference on Monday morning he was in touch with federal and local officials about the volcano, adding that it was under constant monitoring.

“We are ready,” Mr López Obrador said in Spanish.

The disaster prevention center said authorities in the Popocatépetl area were preparing evacuation teams and shelters, and local and state officials also planned to reconnoitre evacuation routes on Monday.

“We have to be absolutely sure that our evacuation routes and signs are correct,” said Ms. Velázquez Alzúa.

Popocatépetl (pronounced poh-poh-kah-TEH-peh-til), also called a god of the rain or the heartbeat of the community, was silent for decades before becoming active in the 1990s. In 2000, a major eruption led to the evacuation of about 50,000 people from the region. Since then, mild to moderate activity from the volcano has prompted officials to occasionally raise alert levels.

It was unclear Monday how long this period of heightened volcanic activity would last.

Jessica Ball, a volcanologist with the United States Geological Survey, said it’s normal for active volcanoes, such as Popocatépetl, to go through cycles of increased activity.

“That’s really just part of being an active volcano,” she said. “There really is no cycle on a human time scale that determines which volcanoes erupt at what time.”

a time-lapse video the center shared on social media on Monday showed the volcano spewing smoke and ash in the early morning.

Officials said on a press conference on Sunday that the state of Puebla, which includes part of the volcano, had set up 35 shelters with room for up to 22,000 people if evacuations were necessary.

Puebla state officials said so on Sunday that to minimize the risk of exposure to falling ash, several public parks in the area would be closed and that schools would conduct classes virtually for the time being.

The National Disaster Prevention Center urged residents living near the volcano not to go outside as much as possible. Those who do go outside must wear a face mask or cover their nose and mouth with a handkerchief, according to the center.

In areas where ash accumulated, the center said residents should cover water containers to prevent contamination, and sweep the ash and collect it in bags.

The volcano alert level was raised a day after Popocatépetl dropped ash from the sky, prompting the temporary closure on Saturday of the two main airports serving Mexico City, about 55 miles northeast of the volcano.

Volcanic ash is particularly dangerous to aircraft, according to the USGS. Falling ash can disrupt aircraft radio transmission and navigation systems, block fuel nozzles, and create hazardous runway conditions that can lead to braking problems.