Ha, joke's on me. The fog came back and the weekend was cool. So gardeners near the coast won't be needing heat protection information for the time being. Probably still pretty hot inland though.
Some flowers, like California poppies and gazanias, don't open fully when the days are foggy, but others open more fully on such days. Good to grow some of these flowers that open in low light in a climate that is often foggy.
Since last week my Oenothera odorata has been blooming. It is an open sort of perennial that eventually reaches nearly 2 feet tall, bearing yellow flowers that are nearly 3 inches across. One common name for the genus Oenothera is evening primrose, and this one really does open in the evening. It is wonderful to see blooming in the dusk or in the dark. There aren't a lot of flowers at a time, and they are held on thin stems with only small, dark, linear leaves, so it looks kind of lanky in the daytime, but in low light the flowers seem to float in the air like fluttery yellow butterflies. Though the flowers stay open longer on foggy mornings, they only last one day, fading before the next evening. I don't think this species has a particular common name. I got my plant from Annies Annuals, and it has seeded itself. I wasn't sure I wanted it back, but decided to leave a few seedlings, and when it started to bloom, I realized that I had been missing it.
Most Nicotiana alata (flowering tobacco) types are also most fully open in evening and morning, though some of the newer cultivars seem to stay open all day. But I have older, tall ones with white and purple flowers that are stunning in the evening and morning, and stay open fully as long as the day is foggy I particularly like the white one, because it has naturalized, coming back each year, though it is sold as an annual. It reaches a couple of feet tall, and stays covered with starry blossoms whenever light is low for weeks in late spring and in summer.
Nasturtium stays open day or night, but has the quality of seeming to glow in the light of late day. In fact, Darwin's daughter presented a paper on the fact that nasturtium glowed in the dark because it was actually phosphorescent. Of course she was quite wrong, but I think the science society at which she spoke probably listened out of respect for her father. How embarrassing if she later realized it!