Residents and tourists were eager to get onto the Ocean Beach Pier when it reopened Friday.
The Ocean Beach Pier. Photo by Chris Stone

The cool summer weather Sunday in San Diego County was expected to give way to a warming trend, peaking later in the week with above-average temperatures, the National Weather Service said.

Another deep marine layer extended all the way into the mountain passes Sunday, somewhat atypical for August, the NWS said.

Enough deepening of the marine layer occurred to produce some patchy drizzle, primarily along the coast between La Jolla and Oceanside, where a few hundredths of an inch fell.

Clouds may be slow to clear again on Monday, with highs a few degrees warmer than Sunday, forecasters said.

High temperatures Monday were forecast to be 73 to 78 near the coast, 79 inland, 79 to 84 in the western valleys, 82 to 87 near the foothills, 82 to 90 in the mountains and 101 to 106 in the deserts.

Some mid-level moisture was expected to be tapped from the eastern Pacific late Tuesday through Thursday. As the atmosphere warms, daytime temperatures may return to average by midweek, and then rise to 5-10 degrees above average inland by Friday.

Given the time of year, it may get quite hot again inland later in the week, where some maximum temperatures were likely to exceed the century mark with widespread moderate heat risk returning.

City News Service contributed to this article.