The month's darkest nights, ranked by moonlight and where the moon sits in the evening sky — plus tonight's verdict with live cloud cover for San Francisco, CA.
Ranked by moon illumination and the moon's evening altitude — a moon below the horizon in the evening means a truly dark sky. Cloud forecasts cover the next 7 days only (Open-Meteo).
Loading forecast…
The darkest nights of the month are the nights around the new moon, when moonlight is at its minimum. The table above ranks San Francisco, CA's next 30 nights by moonlight and evening moon position, and the 7-day outlook adds cloud cover.
Yes — a bright moon washes out all but the brightest stars, the same way city light pollution does. A full moon is roughly 10,000 times brighter than the darkest possible sky. The best deep-sky viewing happens in the week around the new moon.
Once the sun is more than 18 degrees below the horizon the sky is fully dark — roughly 90 minutes after sunset. The moon's position matters more than the clock: nights when the moon is below the horizon in the evening are the dark ones.
Tonight's stargazing verdict → · Sun & moon in San Francisco, CA →