Planning a trip to Southern California during the final month of the year requires looking past the myth of eternal summer. While December weather in Los Angeles remains mild compared to most of North America, daytime highs hover around 67°F to 69°F (19°C), and temperatures drop quickly once the sun sets. You won't need heavy snow gear, but you do need to prepare for cool coastal breezes, chilly evenings dipping to 48°F (9°C), and occasional rainstorms.
Understanding the microclimates and seasonal shifts across the Los Angeles basin helps you pack right and plan outdoor activities without getting caught off guard by sudden temperature drops or wet roads.
Temperature Trends and Daily Patterns
December marks the transition into the coolest stretch of the year for Southern California, though "cool" is relative. Daytime highs typically reach 68°F (20°C) during early afternoons, while overnight lows settle near 49°F (9°C).
You'll find that sunny days still feel warm if you're walking around outdoors in direct sunlight. However, the moment you step into the shadow of a high-rise in Downtown LA or walk along the shoreline in Santa Monica, the temperature drops noticeably.
- Afternoon Warmth: Roughly half of the days in December reach 66°F or higher, with occasional warm Santa Ana wind conditions pushing temperatures past 75°F.
- Evening Chill: Nighttime temperatures slide fast. By 9:00 PM, you'll want a sweater or light jacket, especially if you're near the water.
- Microclimate Variations: Inland valleys like the San Fernando Valley often experience colder mornings than the immediate coast, while coastal zones deal with damp marine layers.
Rainfall and Winter Storms
Los Angeles has a Mediterranean climate, meaning its winters are its primary rainy season. December averages about two to three inches of total precipitation, usually spread across four to six wet days.
A typical storm clears out within 24 hours, leaving behind exceptionally crisp, clear air and snow-capped mountain views of the San Gabriel range. However, when atmospheric rivers hit the region, downpours can cause localized flooding and heavy traffic delays on freeways like the I-405 and I-10.
- Rain Gear: Pack a compact umbrella or a water-resistant shell. Heavy rain boots aren't necessary unless you plan on hiking muddy trails.
- Traffic Impact: LA drivers adjust slowly to wet conditions. Give yourself extra transit time if you encounter rain during your stay.
- Snow in the Mountains: While the city basin stays green and wet, nearby local resorts like Big Bear often receive enough winter precipitation for snow operations.
Sunshine and Daylight Hours
Even in mid-winter, Los Angeles remains a bright destination. The city claims roughly seven to eight hours of direct daily sunshine, outperforming most of the United States during December.
Days are short, though, with the sun setting around 4:45 PM. This early twilight catches many visitors off guard who plan late-afternoon hikes in Griffith Park or coastal walks in Malibu. Plan your outdoor itineraries for the late morning or early afternoon to maximize natural light.
What to Pack for December in LA
Dressing in layers is the golden rule for Southern California winters. Locals transition from t-shirts in the afternoon to wool coats or puffers by evening.
- Daytime Basics: Jeans, long-sleeve shirts, light sweaters, and comfortable walking shoes.
- Evening Outerwear: A sturdy jacket, fleece, or medium-weight coat for nights out.
- Footwear: Sneakers for urban exploration. Waterproof trail shoes if you plan on exploring rugged parks after a storm.
- Sun Protection: Don't skip sunglasses and sunscreen. The winter sun sits lower in the sky and can still cause glare and sunburn during midday hours.
For official local forecasts and current atmospheric advisories before you fly, check the National Weather Service Los Angeles.
Swimming and Beach Conditions
Can you swim in Los Angeles in December? For most visitors, the answer is no. The average sea temperature drops to 61°F (16°C), which feels biting cold without a wetsuit.
Surfers regularly hit breaks in Malibu and Manhattan Beach wearing thick wetsuits, but casual bathers stick to walking on the sand. December is prime time for coastal scenery, tide pooling, and spotting migrating gray whales offshore rather than lounging in swimwear.
Frequently Asked Questions
Does it ever freeze in Los Angeles during December?
Freezing temperatures in the immediate urban basin and coastal zones are exceptionally rare. While frost can occasionally form in outlying agricultural valleys or high-elevation foothill neighborhoods, temperatures in central LA almost never drop below 40°F (4°C).
How do Santa Ana winds affect December weather?
Santa Ana winds are strong, dry offshore air currents that occasionally sweep down from the desert in winter. They push daytime temperatures well above normal—sometimes into the high 70s—while dropping humidity levels significantly and increasing wildfire risks across brush-heavy hillsides.
Are outdoor attractions crowded in December?
Visitor traffic spikes around the Christmas and New Year holidays, particularly near major theme parks like Universal Studios Hollywood. However, early-to-mid December is a relatively quiet window for museums, outdoor markets, and beach walks.
How much daylight do you lose in December?
December features the shortest days of the year, with sunset occurring around 4:43 PM. Twilight is relatively brief, meaning darkness sets in quickly once the sun drops behind the horizon.
