California weather in December
December splits California wide open: Palm Springs runs 69° afternoons while South Lake Tahoe tops out near 43°.
Based on 12 weather stations. Twelve stations from Death Valley to the Sierra — California holds most of the country’s climates inside one border, and no state needs its regions kept apart more than this one.
Southern California
Highs 64–68°, nights 40–50°, and 1.7–2.9 in of rain in a typical December.
| Place | Highs / lows | Wet days | The short version |
|---|---|---|---|
| Los Angeles | 67° / 48° | 4 | Storm weeks and bright cold ones, in no fixed order. |
| Anaheim | 68° / 46° | 3 | Cool, damp at times, and mobbed once school lets out. |
| San Diego | 66° / 50° | 3 | Short days, soft rain, and sunsets worth planning around. |
| Santa Barbara | 64° / 40° | 4 | Genuinely wet, and colder after dark than anyone packs for. |
Central Coast
Highs 61–62°, nights 39–43°, and 2.8–4.0 in of rain in a typical December.
| Place | Highs / lows | Wet days | The short version |
|---|---|---|---|
| Monterey | 62° / 43° | 6 | Wet, dark, and quietly beautiful between the fronts. |
| Santa Cruz | 61° / 39° | 6 | Frosty inland nights, and the winter surf at full size. |
Bay Area & Wine Country
Highs 57–58°, nights 38–47°, and 3.8–4.8 in of rain in a typical December.
| Place | Highs / lows | Wet days | The short version |
|---|---|---|---|
| San Francisco | 58° / 47° | 8 | Soggiest weeks of the lot, broken by fierce blue afternoons. |
| Napa | 57° / 38° | 7 | Coldest nights, wettest weeks, and nobody on the Silverado Trail. |
The Deserts
Highs 66–69°, nights 41–46°, and 0.3–0.7 in of rain in a typical December.
| Place | Highs / lows | Wet days | The short version |
|---|---|---|---|
| Palm Springs | 69° / 46° | 1 | Big sun, low angle, and a properly cold hour after dark. |
| Death Valley | 66° / 41° | 1 | Mild sun, frigid daybreak, and the darkest sky anywhere. |
The Sierra
Highs 43–46°, nights 18–28°, and 3.5–5.6 in of rain in a typical December.
| Place | Highs / lows | Wet days | The short version |
|---|---|---|---|
| Yosemite Valley | 46° / 28° | 9 | Snow on the domes, and storms queued up all month. |
| South Lake Tahoe | 43° / 18° | 11 | Winter proper — carry chains whether or not you need them. |
Each place above has its own page for the full story — what the month feels like, what to pack, and whether the timing is right.