The 4.3 magnitude quake was reported just before 3am local time on Monday morning. 2 An earthquake has hit parts of California Credit: USGSTremors were felt across California, including in San Francisco, according to the US Geological Survey. Tsunami warning issued for Alaska after massive 7.8 magnitude earthquakeLight tremors were felt in Sacramento - around 90 miles from San Francisco, according to the USGS. Meanwhile, San Francisco fire chiefs have urged people to only call 911 for emergencies only. The most powerful earthquake to hit California was the 1906 Great San Francisco earthquake, which had an estimated 7.9 magnitude.