This year, a bright waxing gibbous moon will interfere with the Geminids throughout most of the peak night. Your best bet is to watch from moonset — at 4:45 a.m. Saturday morning in the Bay Area — until dawn.
NASA reports that the Geminids are a relatively young meteor shower, with the first sightings occurring in the 1830s with rates of about 20 per hour.
Over the decades the rates have increased, regularly spawning between 80 and 120 per hour at its peak on a clear evening.Here's more from know from EarthSky.org
Radiating from near the bright stars Castor and Pollux in the constellation Gemini the Twins, the Geminid meteor shower is one of the finest meteors showers visible in either the Northern or the Southern Hemisphere. To help find the Geminids, look for Jupiter, the fourth brightest celestial body in all the heavens, right in front of the constellation Gemini.
The meteors are plentiful, rivaling the August Perseids, with perhaps 50 to 100 meteors per hour visible at the peak.