The weather is developing according to fairly normal summertime patterns, forecasters said.
Temperatures will ramp up from 88 degrees on Wednesday to 95 degrees on Friday in Pasadena. The heat is expected to peak at 99 degrees on Saturday and then decline to 89 degrees by next Wednesday.
In the valleys, temps will reach the low 100s, six to eight degrees above normal in the San Fernando and Antelope valleys by the weekend, because of high pressure, said National Weather Service meteorologist Curt Kaplan.
The NWS forecast a mix of sunny and partly cloudy skies in LA County today; 79 on Mount Wilson; 80 in Avalon; 83 in Long Beach; 85 in Downtown L.A.; 90 in San Gabriel and Burbank; 91 in Saugus; 95 in Woodland Hills; and 96 in Palmdale and Lancaster.