Low pressure over California was expected to weaken early this week with high pressure to the east expanding across the area through the weekend, the National Weather Service said.
A warming trend should continue through the weekend with high temperatures peaking around Sunday at 5 to 10 degrees above average, forecasters said.
The marine layer may decrease in depth with night and morning low clouds becoming patchier and limited mostly to coastal areas by the weekend.
Along the coast Tuesday, it was expected to be mostly partly cloudy with high temperatures from 76 to 80 degrees, the NWS said. Inland valleys were expected to be mostly sunny with highs from 80 to 85. It should be mostly sunny in the mountains with highs from 76 to 85. The deserts were predicted to be mostly sunny with highs from 95 to 98.
The marine layer was still near 2,500 to 3,000 feet deep Tuesday with coastal low clouds extending inland across much of the San Diego County valleys. Coverage was patchier across southern coastal areas.
High pressure to the east was predicted to continue to move slowly westward and be centered over northwest Mexico on Sunday, then begin to weaken early next week.
The heat risk for next weekend could be near thresholds for an excessive heat warning for the lower deserts, and for heat advisories for the valleys, lower elevations of the mountains, and inland coastal areas.
