Right up the hill in Newcastle, they have hills upon beautiful hills of citrus farms, mainly planted to Satsuma Mandarins. Citrus does quite well here, except for the occasional freeze, where some varieties require protection. I ran C9 Christmas lights over my potted citrus, and I only saw some slight die-back on the young new shoots that were pushing out from a Late Fall pruning. At my place, I measured down to 18F on one night, and we had at least 5 days below 32F. I assume it hit Sacramento similarly, though the rivers there have a way of buffering the temps somewhat.