Planning a trip to Southern California during the winter months requires looking past the postcard myth of endless 80-degree summer beach days. Los Angeles CA weather in December brings a distinct shift: crisp daytime highs hover around 66°F (19°C), while evenings drop to a brisk 49°F (9°C). While it's far milder than winters in the Northeast or Midwest, you won't be lounging in a swimsuit on Santa Monica beach without a heavy towel and a warm layer.
December is officially part of the region's rainy season, meaning precipitation and sudden coastal marine layers play a major role in how your daily itinerary unfolds. If you're packing for a holiday vacation or a year-end getaway, understanding the atmospheric patterns of the City of Angels helps you avoid getting caught off guard by chilly evening breezes or sudden downpours.
Temperature Breakdowns and Daily Shifts
Winter temperatures in Los Angeles remain comfortable by national standards, but the daily swing from afternoon warmth to evening chill catches many travelers unprepared.
Daytime highs generally reach between 65°F and 68°F during the first half of the month, cooling slightly toward the low 60s as Christmas approaches. When the sun is out, the solar intensity feels much warmer than the air temperature suggests, making outdoor sightseeing pleasant. However, the moment the sun dips behind the horizon or a cloud rolls in, temperatures drop rapidly. Overnight lows routinely settle near 48°F to 50°F.
- Morning conditions: Frequently start with a crisp chill or a low coastal fog that burns off by late morning.
- Afternoon peak: Usually the warmest window, ideal for hiking Griffith Park or walking along the pier.
- Nighttime drop: Requires a proper coat, especially if you're attending outdoor holiday light displays or rooftop events.
According to historical climate data maintained by the National Weather Service, microclimates heavily dictate what you'll experience hour by hour. Coastal neighborhoods like Malibu, Santa Monica, and Manhattan Beach stay cooler due to ocean breezes, while inland valleys such as the San Fernando Valley can experience wider temperature extremes, boasting warmer afternoons and colder nights.
Rainfall and Winter Storm Patterns
Many visitors assume Southern California is immune to rain, but December stands out as one of the wettest months of the year for the basin. On average, the city records around two to three inches of total precipitation, usually concentrated across four to six wet days.
Rain in Los Angeles rarely takes the form of a gentle, all-day drizzle. Instead, when Pacific storm systems move onshore, they can dump heavy rain in short bursts, often accompanied by localized flooding on major freeways like the 405 or the 101.
- The Santa Ana Winds: On dry days when it isn't raining, high-pressure systems over the Great Basin can trigger the famous Santa Ana winds. These offshore gusts sweep warm, dry air down from the mountains, driving temperatures up unexpectedly and drastically dropping humidity levels, which simultaneously elevates local wildfire risks.
- Ocean conditions: Water temperatures hover around 58°F to 60°F (14°C to 15°C). Swimming without a thick wetsuit is uncomfortable for most people, though beach walking remains a staple activity.
What to Pack for LA in December
Packing for a winter trip to Southern California is all about strategic layering. Bulky winter parkas are unnecessary, but a functional capsule wardrobe keeps you comfortable from morning hikes to late-night dinners.
- Light to medium outerwear: Bring a stylish wool coat, a fleece-lined denim jacket, or a packable down puffer for evenings and breezy coastal walks.
- Versatile layers: Pack breathable cotton long-sleeve shirts, sweaters, and cardigans that you can peel off when the afternoon sun peaks.
- Pants and jeans: Full-length denim, chinos, or thick trousers are standard. Leave shorts at home unless you plan on heavy indoor workouts.
- Rain gear: A compact travel umbrella and a water-resistant shell jacket ensure a sudden downpour doesn't ruin your plans.
- Footwear: Comfortable walking shoes or clean sneakers handle urban exploring and theme parks well. Waterproof boots aren't strictly necessary unless a major storm hits during your stay.
Neighborhood Microclimates to Keep in Mind
Los Angeles spans over 500 square miles of diverse terrain, meaning the weather you experience depends heavily on your exact coordinates.
If you spend the day touring Universal Studios Hollywood in the valley, you might enjoy warm, sunny afternoon weather. If you head down to the Santa Monica Pier an hour later, a thick layer of marine air can sweep in off the Pacific, dropping the perceived temperature by ten degrees instantly. Checking local neighborhood forecasts rather than a generic city-wide app ensures accurate preparation.
Frequently Asked Questions
Can you swim in the ocean in Los Angeles in December?
For the vast majority of visitors, no. Ocean temperatures plunge to around 58°F, making recreational swimming or surfing uncomfortable without a high-grade wetsuit. Wading along the shoreline or sunbathing on a warm afternoon is entirely doable, though.
Does it ever snow in Los Angeles?
Snow within the actual Los Angeles basin or at sea level is virtually non-existent. However, the nearby San Gabriel Mountains often receive a dusting of snow on peaks like Mount Baldy, creating a scenic snowy backdrop visible from the city on clear days.
How early does the sun set in December?
Because December sits right around the winter solstice, sunset occurs early—usually between 4:45 PM and 5:00 PM. Plan your outdoor sightseeing, photography, and hiking excursions for the morning and early afternoon to maximize daylight hours.
Are outdoor attractions still open during rainy days?
Major theme parks and outdoor venues generally remain open during light rain, though extreme downpours can prompt temporary closures of specific outdoor rides or shows. Always check official venue apps if a storm warning hits the local news.
