Temperatures across interior Southern California will climb dramatically over the next few days, as a prolonged, dangerous heat wave begins Wednesday and could persist into next week.

“This is a more impactful, more significant heat wave than really what we’ve seen for the majority of the summer. We’ve had kind of more of a cooler pattern, a lot of marine layer clouds. And so this might catch some people by surprise … but [it] definitely looks pretty warm,” said Lisa Phillips, a meteorologist with the National Weather Service.