10 Months out of the year the weather in SoCal is almost perfectly predictable;
March through May - Cool, sunny and dry
June - Foggy mornings called "June Gloom", sunny afternoons, warm and dry
July through October - Sunny, very warm and dry
November and December - Cool, sunny and dry
But January and February are the two months out of the year where things aren't as predicable. Sometimes it will be sunny and windy and hot with sometimes destructive Santa Ana Winds blowing in from the desert. Sometimes it will be clear and crisp with cold nights down into the 40's. Sometimes it will be grey and overcast and drizzly with highs in the 50's and remind you of Seattle. Sometimes it will be very stormy with torential rain and wind and a series of cold storms blowing in from the North Pacific every 36 hours with snow piling up in the foothills and low mountains around Orange County. And sometimes it will be just regular old rain and showers that come and go with a cold wind cutting into you. And then, sometimes it will be sunny and 75 degrees and perfectly delightful and you laugh at the TV news that shows pictures of 3 feet of snow in Boston and New York and Chicago.
The bottom line; you never know what you'll get in SoCal in January and February. It's completely random and unpredictable from year to year, week to week, and day to day.