Seasonal figures below use a 2025 reference year. Choose a date in the planner above for that day’s times, golden hour, twilight, and daylight milestones.
Seasonal Sun Milestones in South San Francisco
South San Francisco's 8 PM sunsets run from about May 1 to August 16 — 108 evenings in a typical year. The wider season of sunsets at 7 PM or later lasts 202 days, from March 9 to September 26. At the other end of the year, sunsets before 5 PM begin around November 14 and last until December 28.
Days in South San Francisco first reach 12 hours of daylight around March 17, a few days before the March equinox, and drop back under 12 hours after September 25. Days with at least 14 hours of daylight run from May 8 to August 3. Days with less than 10 hours of daylight run from November 20 to January 20 (62 days).
The Sun's rising point moves along the horizon too. Around the June solstice it rises in the ENE (59°) and sets in the WNW (301°); by the December solstice it rises in the ESE (119°) and sets in the WSW (241°). That is a 60° swing — worth knowing when choosing a west-facing viewpoint for a summer sunset or an east-facing window for winter morning light.
Dates use the 2025 reference year. Clock-time milestones near daylight-saving changes move with the second Sunday in March and the first Sunday in November.
Daylight Through the Year in South San Francisco
South San Francisco sits at 37.65°N, a mid-latitude position that gives it a balanced but noticeable seasonal rhythm. The difference between its longest and shortest day is 5h 13m.
On the summer solstice around June 21, South San Francisco receives 14h 46m of daylight — the longest day of the year. By the winter solstice around December 21, that shrinks to 9h 34m, the shortest day. At the spring and autumn equinoxes, day and night are nearly equal at about 12h 9m, as they are everywhere on Earth.
Sunset moves fastest around September, when it shifts by up to 1.6 minutes a day in South San Francisco, and barely moves for weeks around the solstices. See how sunrise and sunset change through the year for why.
The Sun's Path Over South San Francisco
Where the Sun sits in the sky over South San Francisco depends on the season, and the contrast between summer and winter is set by the city's latitude of 37.65°N. On the summer solstice the midday Sun reaches 75.8° above the horizon in South San Francisco, its highest point of the year. On the winter solstice the midday Sun only reaches 28.9°, sitting much lower in the southern sky and casting long shadows even at noon.
Those roughly 47 degrees separating the summer and winter midday Sun are exactly what give South San Francisco its seasons.
The live sun path at the top of this page shows the Sun's altitude and compass bearing for the current moment or any chosen date.
Earliest and Latest Sunrises and Sunsets in South San Francisco
It is natural to assume South San Francisco sees its latest sunset on the longest day of the year, but it does not. The latest sunset actually falls around June 27 at about 8:35 PM, while the earliest sunset comes around December 6 at roughly 4:51 PM — noticeably before the December solstice.
On the morning side, the earliest sunrise in South San Francisco is around June 13 at 5:48 AM, and the latest sunrise around November 1 at 7:35 AM. The equation of time and daylight saving pull these dates away from the solstices — explained in why the latest sunset isn't on the longest day.
How Daylight Saving Time Moves Sunrise and Sunset in South San Francisco
South San Francisco, California changes its clocks twice a year, and both changes are visible in this page's numbers. On the second Sunday in March, South San Francisco springs forward and the evening changes overnight: sunset jumps from about 6:11 PM on Saturday to about 7:12 PM on Sunday. The price is paid at dawn — sunrise slips from around 6:30 AM back to 7:29 AM, so mornings turn dark again just as they were brightening.
The reverse comes on the first Sunday in November, when clocks fall back: sunset drops from about 6:11 PM to 5:10 PM in a single day — the abrupt start of the early-dusk season — while sunrise brightens from around 7:35 AM to 6:36 AM.
Only the clock label shifts on those Sundays; the times above are for a typical year. More in how daylight saving time changes sunrise and sunset.
Golden Hour & Blue Hour Photography in South San Francisco
For photographers in South San Francisco, California, the planner shows your selected date's morning and evening golden-hour and blue-hour windows. Choose Today, Tomorrow, or a date in the calendar; all clock times are calculated in South San Francisco's local timezone.
Golden "hour" is a misnomer — its length in South San Francisco depends on the season, because it lasts as long as the Sun takes to climb from the horizon to 6° (or descend back). Around the equinoxes it runs about 35 minutes; near the June solstice, when the Sun rises and sets at a shallower angle, it stretches to roughly 39 minutes, and near the December solstice it lasts about 41 minutes.
See the golden hour guide and blue hour guide for how to plan a shoot around these windows.
Solar Energy Potential in South San Francisco
Under clear skies, South San Francisco, California receives about 5.3 peak sun hours per day averaged across the year — from roughly 2.2 in December up to 8.3 in June. One peak sun hour equals one hour of sunlight at full intensity (1 kW/m²), the standard unit for estimating solar panel output.
Because South San Francisco sits at 37.7°N, a fixed, south-facing panel captures the most energy over the year when tilted at roughly 38° from horizontal — about equal to the latitude. If you adjust the tilt seasonally, flatten to about 23° in summer, when the Sun rides high, and steepen to about 53° in winter, when it stays low.
These are clear-sky upper bounds from South San Francisco's solar geometry, not a forecast; clouds, shading, and equipment lower real output. See what peak sun hours mean.
How South San Francisco Compares
Daylight in South San Francisco swings 5h 13m between the June and December solstices. That is within a quarter-hour of the median of 5h 16m across the 1,847 cities on this site, making South San Francisco close to typical for the United States. By that measure South San Francisco ranks 958th of 1,847 nationally, and 72nd of the 307 California cities listed here — counting from the largest swing down.
South San Francisco sits about 2.4° west of 120°W — the meridian Pacific Time is built around. Longitude alone therefore puts mean solar noon roughly 10 minutes after clock noon in standard time, so the Sun runs behind the clock here, which is why evenings hold light later than the time zone would suggest. The equation of time then moves true solar noon up to about 16 minutes either side of that through the year.
About Sun Times in South San Francisco
South San Francisco, California, has an estimated urban-area population of 64,305. Its primary county or equivalent is San Mateo; its center is at 37.65°N, 122.42°W. Clocks here follow Pacific Time, which is the timezone all sunrise, sunset, golden-hour and twilight times on this page are shown in.
Times are computed for South San Francisco's city-center coordinates, so towns to the east see each event slightly earlier and towns to the west slightly later; the nearby-cities list above shows the typical gap.