Douglas, the fourth tropical storm this year, is more than 1,000 miles south of San Diego and is not likely to turn into a hurricane over the weekend, according to the National Weather Service in San Diego.
With winds clocked at 65 m.p.h., the storm is hovering near Acapulco and moving slowly north at 5 m.p.h, said forecaster Wilbur Shigehara.
High-altitude winds may bring in some moisture from the storm, causing increasing cloudiness and humidity in the mountains and deserts Sunday, but no rain is expected at least through the weekend, he said.
Shigehara noted, however, that tropical storms are unpredictable. Hurricanes feed off warm ocean waters, and the water temperatures off San Diego are 69 degrees.
"Yellowtails start biting when the water is warm, and the yellowtails are boiling to the south of us," he said.
The weather service is keeping an eye on satellite pictures of Douglas, but, in the meantime, people attending the Del Mar Fair and enjoying the first weekend of summer should be able to count on fair skies, he said.
After warming up to it for weeks, summer officially arrived Thursday, marking the longest day of the year. At 8:33 a.m., the sun reached its summer solstice, its farthest point north of the Equator for the year.
The first weekend of summer will be typical for this time of year, with lots of sunshine, and night and morning low coastal clouds.
"If we didn't have the protective clouding holding down temperatures in the morning, it would be blistering hot," Shigehara said.
At the beaches, temperatures will vary from 66 to 71 today and through the weekend, Shigehara said. Despite the southerly storms, surf will peak at only 2 to 3 feet.
Coastal temperatures are expected to range from 70 to 78 during the day and 58 to 64 at night, with inland highs pushing into the 80s.