A year ago, the warm El Nino was strengthening and that helped to create a phenomenon known as the Mayan Express, which funneled moisture from the Caribbean and Gulf of Mexico combined with an "atmospheric river" of Pacific water vapor that swept in, inundating the Sabine River, causing operators of Toledo Bend to open the dam's spillways, drowning Deweyville. A similar kind of "atmospheric river" affecting the West Coast funnels vapor from the Hawaiian islands toward California in an phenomenon called the "Pineapple Express," Humphrey said.