 A searing heat wave gripped large areas of the U.S. on Monday with record daily high temperatures in Oregon suspected to have caused four deaths in the Portland area following a motorcyclist's death in dangerous heat over the weekend in Death Valley, California. More than 146 million around the country were under heat alerts Monday, especially in western states. California, Nevada, Arizona, Oregon, Washington, and Idaho were under an excessive heat warning, according to the National Weather Service, while parts of the East Coast, as well as Alabama and Mississippi, were under heat advisories.