Hourly Weather - Imperatriz, Brazil

The gentle slope of Mauna Loa as seen from the flanks of Mauna Kea to the north. (USGS/HVO) Federal officials raised the alert level Tuesday for the world's largest active volcano, Hawaii's Mauna Loa, which last erupted in 1984. The U.S. Geological Survey changed the level from "normal" to "advisory" following a steady increase in earthquakes and ground swelling that began in March. An eruption is not imminent, but scientists are closely monitoring Mauna Loa because of its reputation for...