Temperatures much hotter than expected, with San Diego hitting 82

Friday will be the hottest day in more than two months, with the temperature rising as high as 78 in San Diego and the low to mid-80s across inland valleys and foothills, the National Weather Service said.

A high-pressure system that began to take effect on Thursday will produce mostly clear skies and a weak sea breeze, allowing for significant warming across Southern California, which has experienced unusually persistent cool weather.

Forecasters said that Saturday’s high in San Diego will be a bit cooler, topping out at 73, which is 4 degrees above average. But inland areas will generally be slightly warmer, with lots of readings in the mid-80s.

“Cooling will begin Sunday closer to the coast, reaching farther inland by Monday,” the weather service said in an advisory. “The cooler conditions will continue into Tuesday. The early week temperature change will be most noticeable west of the mountains, especially near the coast although highs in the deserts will be knocked down a few degrees from their peak.”

Forecasters expect the weather to turn warmer toward the middle of next week, with most areas experiencing seasonal highs.

The warm-up represents a dramatic change for the region. Through Wednesday, the average April temperature for San Diego stood at 58.2 degrees — 4.3 degrees below average.

The chilliness follows a cold March. The average temperature was 56.8 degrees, or 3.9 degrees below normal. It was the coldest March since 1991.

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