It’s time to crank up those fans and air conditioners because the next few days are going to be hot.

The first extended heat wave of the season has been forecast for inland regions of the Southland for the rest of the week, with triple-digit temperatures on tap for the San Fernando and Antelope valleys, according to the National Weather Service.

A high-pressure system moving over Southern California from the Pacific Ocean is bringing the heat wave, said David Sweet, a meteorologist with the National Weather Service in Oxnard.