Cloud cover over San Francisco, measured not inferred
Every hour of daylight in July 2026, the satellite classified each patch of the city cloudy or clear. This is the fraction of the time each patch was under cloud. No temperature proxy, no modelling.
Chris Russo · July 2026
SunnyCloudyEach square is one satellite pixel, about 2.2 × 2.9 km · hover for the number
West to east, July middays
Band
% of middays cloudy
% sunny
Pixels
Sunset & Richmond
49%
51%
4
Ocean Beach & outer coast
48%
52%
1
Twin Peaks & Golden Gate Park
37%
63%
4
Castro, Noe, Haight
25%
75%
4
Mission, Potrero, SoMa
23%
77%
3
In July, at midday, the Sunset sits under cloud 49% of the time and the Mission 23%.
Across the 186 midday hours in the month that is roughly 95 sunny hours in the Sunset against 143 in the Mission,
a difference of about two full days of sunshine in a single month, four miles apart.
Limits of this particular map
One month. July 2026 only. July is peak fog season, so this is close to the maximum contrast the city ever shows, not the annual picture.
Pixels are bigger than neighborhoods. At roughly 2.2 by 2.9 km, the Mission and Bernal Heights fall in the same pixel and cannot be separated. Twenty-one pixels cover the city.
One pixel is suspect. The cell north of downtown over open water reads 89% cloudy, far outside every neighbor. Water surfaces and sun glint confuse cloud detection, so treat that square as an artifact.
Cloudy is not the same as no sun. The satellite reports cloud overhead. Thin high cloud the sun burns through still counts as cloudy here.