By Bay City News Service
Today marks the summer solstice in the Northern Hemisphere, when the sun shines directly over the Tropic of Cancer, National Weather Service forecaster Diana Henderson said.
Following today's solstice, the Earth will continue its orbit around the sun on its tilted axis, so that by Sept. 22, the sun will be directly over the equator for the autumnal equinox, Henderson said.
From here on out, the days will gradually become shorter. Today, the sun sets at 8:35 p.m. The sunrise was at 5:48 a.m., making today almost a 15-hour day.
At Chabot Space and Science Center in the Oakland hills, visitors can experience "solar noon" at 1:11 p.m., with the sun is at the highest point in the sky, Chabot staff astronomer Ben Burress said Sunlight coming through the science center's rotunda sends triangular shadows onto the compass rose printed on the floor below.
At solar noon, one of the shadows will line up with the north-pointing arrow, Burress aid.
To celebrate the extra daylight, the Golden Gate National Parks Conservancy has planned a free, family-friendly event on Muir Beach in Marin County Thursday evening.
With storytelling and songs around the bonfire, the 6 p.m. solstice celebration on the first full day of summer aims to teach Bay Area residents about the sun.
Organizers are reminding attendees to bring warm clothing and drinks for when the sun starts to set. Tonight, a bonfire will be held at San Francisco's Ocean Beach.
The summer solstice bonfire, organized by the group Reclaiming, instructs attendees in an online post to meet at the beach near Taraval Street around 7:30 p.m.
Today is expected to be the warmest day this week, Henderson said. Highs along the coast will likely reach the lower 70s.
Inland temperatures are expected to be in the 80s, with some spots reaching the low 90s.
The rest of the week will see high temperatures drop at least 10 degrees in the San Francisco area, with cooler temperatures over the weekend. Warmer weather should return by next week, Henderson said.