California’s power grid will be pushed to near its limit Monday as the state wilts under a blistering and sustained heat wave. With millions of homes and businesses cranking air conditioners to cope with temperatures above 110 degrees Fahrenheit, electricity use in the largest US state is forecast to hit 48.9 gigawatts Monday, the most since 2017. The state’s grid operator has asked residents to conserve as much as possible, warning the system could be short up to 4 gigawatts. “California has been ridiculously hot and will be hot for a good part of the week,” Bob Oravec, a senior...