Sunday's eruption of the Fuego volcano in Guatemala has ended, at least for now, after killing at least 25 people, according to the country's disaster response agency. Guatemala's national agency monitoring earthquakes, volcanos and the weather, has warned that in the wake of the eruption, areas around the volcano may be at risk of what scientists call lahars, which are sort of like very fast mudflows, but filled with rock particles released by the eruption. Despite the name, pyroclastic flows aren't liquids, they're a dense mixture of super-hot rocks—from boulders all the way down to the tiny particles of rock scientists refer to as volcanic ash. Pyroclastic flow can reach temperatures as high as 1500 degrees Fahrenheit and speeds of 50 miles per hour or more, barreling through pretty much whatever is in its path. read more Disclaimer: Chances are that this post was requested by an advertiser.