A modest warming trend was expected in San Diego County Monday through Wednesday, the National Weather Service said.
Night and morning clouds were predicted to become more confined to the coast and western valleys, the NWS said.
The clouds should clear fairly well by late Monday morning for a mostly sunny day.
Low pressure could bring a cooling trend Thursday into the weekend, with a deeper marine layer, more extensive coastal clouds, and a slight chance of showers this weekend, forecasters said.
Monday's coastal weather was expected to be mostly sunny with high temperatures from 71 to 74 degrees. Inland valleys were expected to be 76. It should be mostly sunny in the mountains with highs from 78 to 87, and the deserts were predicted to be mostly sunny with highs around 98 degrees.
High pressure may slightly build the next couple days, which should boost high temperatures through Wednesday and restrict the nocturnal cloud cover closer to the coast through Wednesday.
The warmest day this week appeared to be Wednesday, forecasters said.
A long wave trough of low pressure begins to amplify and sag southward over the western U.S. Thursday into Saturday, and the trough amplification reaches its maximum this weekend. By then the marine layer should deepen to extend coastal clouds into the mountains. That would produce areas of drizzle from the coast to the foothills.
Northwest winds were expected to gust to 20 knots over the outer waters Monday afternoon and again Tuesday afternoon.
