City residents and out-of-town visitors flock to Ocean Beach. File photo by Chris Stone

Temperatures will continue to run above seasonal norms through midweek under continued high pressure, but a cooling trend is ahead, according to the National Weather Service forecast.

“Late this week is when noticeable changes will be felt when it will turn much cooler with even a chance of drizzle and/or light rain,” the weather service said.

Highs on Monday will be 72 to 77 near the coast, 80 inland, 80 to 85 in the western valleys, 84 to 89 near the foothills, 81 to 89 in the mountains and 98 to 103 in the deserts.

Slow cooling will continue to work inland over the next few days as the high-pressure system weakens and the marine layer rebuilds, forecasters said.

“The shallow moist layer will favor more dense fog development tonight along the coast, and then a bit farther inland in the coming days,” the weather service said. “More significant cooling will arrive late this week as a trough passes.”

There is the potential for a significant pattern change next weekend with a large-scale low-pressure trough over southwest Canada and the northern Rockies developing, forecasters said.

“This trough could bring the chance for precipitation, strong winds, and cooler weather, or all of the above, with a slight risk of an offshore pattern developing as well,” the weather service said.

— From staff and wire reports

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