Topline:
As an area of high pressure strengthens over Southern California, temperatures are expected to climb into the triple digits on Wednesday and Thursday, according to the National Weather Service.
What to expect: In the desert, highs will be from 102 to 118 degrees. Inland, temperatures could climb as high as 104. Along the coast, expect the heat wave to top out around 85 midweek.
Air quality: The South Coast Air Quality Management District issued a smog warning, saying elevated ozone pollution is expected Tuesday through Thursday in inland areas, including Pasadena and Corona. You can check real-time air quality on AQMD's website.
By the weekend: The high pressure will weaken, and onshore flow will bring in a cooling marine layer, dropping temperatures to slightly below normal across much of the area. Desert areas are expected to remain in the triple digits.