California heat could threaten long-standing temperature records. How long will warm weather last?This week, state officials launched a new tool that ranks heat wave severity and predicts impacts from sweltering temperatures at the neighborhood scale.

A map shows areas in California where temperatures are expected to surpass 100 this week. There has been an early-season heat wave in Southern and Central California. On Monday, people in four states including California were warned of dangerous fire weather condition s.

Southern California is bracing for a surge of summerlike heat this week with inland temperatures expected to climb into the 90s and potentially hit the triple digits in the San Fernando Valley, according to the National Weather Service.