December in Los Angeles typically offers mild daytime temperatures, averaging between 15-20C (59-68F). Rainfall is possible, contributing to the city’s average annual precipitation. While snowfall is rare in the city itself, the nearby mountains often experience significant snowfall, creating opportunities for winter recreation. This period represents a transition between the late autumn and the start of the winter season.
Understanding typical climate conditions for this period is valuable for a variety of purposes. Travelers can plan appropriate attire and activities. Businesses dependent on weather, such as tourism and outdoor recreation, can adjust their operations accordingly. Residents can prepare for potential rain and utilize the cooler temperatures for seasonal activities. Historical weather data provides context for present conditions and assists in long-term planning, such as water resource management and urban development.
The following sections will explore historical weather patterns for December in Los Angeles, discuss predicted conditions for December 2024 (as they become available), and offer guidance for travelers and residents regarding expected temperatures, precipitation, and relevant activities.
1. Average Temperatures
Average temperatures play a crucial role in characterizing Los Angeles weather in December. While daily temperatures can fluctuate, the average provides a baseline for understanding typical conditions. These averages are derived from historical data, offering insight into expected daytime highs and nighttime lows. For example, a typical December day might see highs in the mid-60s Fahrenheit (around 18-19C) and lows in the mid-50s Fahrenheit (around 12-13C). This relatively mild temperature range distinguishes Los Angeles from colder climates and influences local activities, attire, and energy consumption.
The significance of average temperatures extends beyond daily experience. These figures contribute to broader climate analysis, allowing for comparisons across years and decades. Deviations from established averages can signal climate shifts or unusual weather patterns. Furthermore, average temperatures inform agricultural practices, water resource management, and urban planning. Understanding historical averages allows for informed decision-making in these sectors, optimizing resource allocation and mitigating potential risks associated with temperature fluctuations. For instance, knowing the average temperature helps determine the best time to plant winter crops or predict water demand for irrigation.
In summary, average temperatures serve as a foundational element in understanding Los Angeles weather in December. They provide a practical reference point for daily activities and inform broader climate analysis. The ability to interpret and apply this data is essential for adapting to current conditions, planning for future scenarios, and understanding the complex interplay of factors contributing to the region’s unique climate.
2. Rainfall Probability
Rainfall probability forms a critical component of Los Angeles weather in December. December falls within the region’s wetter season, influenced by Pacific storm systems. Understanding the likelihood of precipitation is essential for various sectors, including agriculture, water resource management, and outdoor event planning. Rainfall probability is not a guarantee of precipitation, but rather represents the statistical chance of measurable rainfall occurring at a specific location within a given timeframe. This probability is influenced by a complex interplay of atmospheric conditions, including temperature, humidity, wind patterns, and the presence of weather systems.
The practical significance of rainfall probability is substantial. For the agricultural sector, rainfall influences irrigation schedules and crop yields. Water resource managers utilize rainfall probability forecasts to predict reservoir levels and manage water distribution networks. Outdoor events, common during the relatively mild December weather, often incorporate rainfall probability into logistical planning and contingency measures. A higher probability of rain might necessitate alternative arrangements or cancellations, while a lower probability might allow events to proceed as planned. Construction projects, sensitive to weather delays, also factor rainfall probability into scheduling and resource allocation. Accurate predictions can mitigate potential disruptions and optimize project timelines.
Reliable rainfall probability forecasts, based on historical data and current weather models, provide valuable information for decision-making across multiple sectors. While challenges exist in predicting highly variable weather patterns, advancements in meteorological science continue to improve forecast accuracy. Understanding rainfall probability contributes significantly to effective planning and preparation, minimizing disruptions and maximizing opportunities presented by Los Angeles weather in December.
3. Sunshine Hours
Sunshine hours significantly influence Los Angeles weather in December. Reduced daylight duration compared to summer months impacts temperatures, plant life, and human activity. Understanding this seasonal shift is crucial for comprehending the overall December climate profile.
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Impact on Temperatures
Fewer sunshine hours directly correlate with lower average temperatures. Reduced solar radiation limits daytime heating, leading to cooler days and nights. This effect is amplified by shorter days and the lower angle of the sun during winter.
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Influence on Plant Life
Decreased sunlight affects plant growth and development. Many plants enter dormancy or reduce photosynthetic activity during this period due to limited light availability. This seasonal change impacts local ecosystems and agricultural practices.
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Effects on Human Activity
Shorter daylight hours influence daily routines and recreational opportunities. Outdoor activities are often constrained by reduced daylight availability. The shorter photoperiod can also influence human biological rhythms, sometimes impacting mood and sleep patterns.
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Relation to Tourism and Recreation
Sunshine hours directly influence tourism and outdoor recreation. While December offers mild temperatures, reduced daylight can impact beach activities and other outdoor pursuits. Visitors should consider the shorter days when planning itineraries and choosing appropriate attire.
In conclusion, sunshine hours play a critical role in shaping Los Angeles weather in December. The reduced daylight influences temperatures, plant life, human activity, and tourism. Recognizing the impact of sunshine hours provides a comprehensive understanding of the December climate and informs planning for various activities and sectors.
4. Humidity Levels
Humidity levels contribute significantly to the character of Los Angeles weather in December. Generally, December experiences moderate humidity compared to the more humid summer months. This decrease stems from cooler air temperatures, which hold less moisture than warmer air. The Pacific Ocean’s influence moderates humidity levels, preventing extremes typically found in inland desert regions. Understanding December humidity is crucial for comfort, health, and various industries.
Moderate humidity in December often results in comfortable conditions for residents and visitors. Lower humidity compared to summer reduces the perception of heat, making outdoor activities more enjoyable. However, Santa Ana winds can periodically decrease humidity significantly, increasing the risk of wildfires and respiratory issues. These dry winds, originating from the desert, create arid conditions that can exacerbate existing health conditions and pose challenges for fire management. Conversely, periods of higher humidity, though less frequent in December, can lead to fog formation, particularly in coastal areas, affecting visibility and transportation. The interplay between these varying humidity levels contributes to the dynamic nature of Los Angeles weather in December.
Practical implications of December humidity extend to various sectors. Agriculture benefits from moderate humidity, reducing the need for excessive irrigation. Construction activities experience fewer weather-related delays compared to wetter months. The tourism industry capitalizes on the generally comfortable conditions to attract visitors seeking respite from colder climates. Recognizing the influence of humidity is crucial for understanding the multifaceted nature of Los Angeles weather in December and its impact on various aspects of life in the region.
5. Ocean Temperatures
Ocean temperatures play a crucial role in shaping Los Angeles weather in December. The Pacific Ocean, a dominant presence along the California coastline, significantly influences air temperature, humidity, and fog formation during this period. Understanding the relationship between ocean temperatures and atmospheric conditions provides valuable context for interpreting December weather patterns.
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Coastal Air Temperatures
Ocean temperatures moderate coastal air temperatures, preventing extreme fluctuations. The ocean acts as a large heat reservoir, absorbing solar radiation during warmer months and releasing it slowly during cooler periods. This moderating effect results in milder winters along the coast compared to inland areas, where temperature variations are more pronounced.
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Humidity and Fog Formation
Cooler ocean temperatures in December contribute to lower humidity levels compared to summer. However, the relatively warm ocean surface still provides moisture to the overlying air. When this moist air encounters cooler air masses or land surfaces, fog can form, particularly in coastal areas and valleys. This fog, prevalent during December mornings, can significantly impact visibility and transportation.
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Influence on Precipitation
Ocean temperatures influence precipitation patterns by affecting the temperature and moisture content of air masses moving onshore. Warmer ocean temperatures can increase the intensity of rainfall during winter storms. Conversely, cooler ocean temperatures can lead to less intense rainfall or even suppress precipitation altogether. The complex interaction between ocean and atmospheric temperatures determines the type and amount of precipitation experienced in Los Angeles during December.
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Impact on Marine Ecosystems
Ocean temperatures in December directly affect marine ecosystems. Changes in water temperature influence the distribution and behavior of marine organisms. Some species migrate to warmer waters, while others adapt to the cooler conditions. These temperature fluctuations can also impact the timing of breeding cycles and the availability of food sources within the marine environment.
In summary, ocean temperatures represent a fundamental factor influencing Los Angeles weather in December. The interplay between ocean and atmospheric conditions determines temperature ranges, humidity levels, fog formation, and precipitation patterns. Recognizing the influence of ocean temperatures provides a comprehensive understanding of the complex dynamics shaping December weather in the region and its broader implications for the local ecosystem.
6. Mountain Snowfall
Mountain snowfall significantly influences the Los Angeles region during December. Although Los Angeles itself rarely experiences snowfall, the surrounding San Gabriel Mountains often accumulate substantial snowpack during this period. This snowfall impacts regional weather patterns, water resources, and recreational opportunities. The presence of snow cover at higher elevations influences air temperatures in the basin, contributing to cooler conditions. Melting snowpack in the spring feeds local rivers and replenishes groundwater supplies, crucial for the region’s water security. The snow-capped mountains also create a scenic backdrop and provide opportunities for winter recreation, attracting tourists and boosting local economies.
The relationship between mountain snowfall and regional weather is complex. Snow cover increases albedo, reflecting more solar radiation back into space and reducing overall heating of the area. This can lead to temperature differences between the mountains and the lowlands, influencing wind patterns and atmospheric stability. The amount of snowfall also impacts the timing and volume of spring runoff, which has implications for water resource management and flood control. For example, a heavy snowpack followed by rapid warming can lead to increased river flows and potential flooding, while a light snowpack can exacerbate drought conditions. Understanding these interactions allows for better prediction and mitigation of potential weather-related risks.
Predicting mountain snowfall is challenging due to the complex interplay of atmospheric factors. Elevation, temperature, and precipitation patterns all influence snow accumulation. Accurate snowfall predictions are essential for water resource planning, avalanche forecasting, and managing winter recreation activities. Despite these challenges, advancements in meteorological modeling and remote sensing technologies continue to improve snowfall prediction accuracy, providing valuable information for resource management and public safety. Recognizing the interconnectedness of mountain snowfall and the broader Los Angeles weather system is crucial for effective planning and adaptation in this geographically diverse region.
7. Santa Ana Winds
Santa Ana winds represent a significant weather phenomenon impacting Los Angeles, particularly during autumn and occasionally in December. These strong, dry downslope winds originate from high-pressure systems over the Great Basin and Mojave Desert. Their presence adds a layer of complexity to typical December weather patterns, influencing temperature, humidity, and fire risk. Understanding their characteristics is crucial for comprehending the full spectrum of Los Angeles weather in December.
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Impact on Temperature and Humidity
Santa Ana winds significantly decrease humidity and elevate temperatures. Compression heating as the winds descend from higher elevations can dramatically raise temperatures, sometimes by 10-20F. This rapid warming and drying effect creates a stark contrast to typical December conditions, resulting in an increased risk of wildfires.
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Elevated Fire Risk
The combination of low humidity, high winds, and dry vegetation creates extremely dangerous fire conditions. Santa Ana winds can rapidly spread existing fires and ignite new ones, posing substantial threats to property and human life. Fire agencies heighten their preparedness during Santa Ana wind events due to this elevated risk.
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Influence on Air Quality
Santa Ana winds often carry dust and particulate matter from desert regions, impacting air quality in Los Angeles. This can exacerbate respiratory issues for sensitive individuals and reduce visibility. The strong winds also trap pollutants within the basin, further degrading air quality.
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Interaction with Coastal Conditions
Santa Ana winds can interact with the marine layer along the coast, creating complex weather patterns. The dry, warm air can push the marine layer offshore, leading to sunny and warm conditions at the coast. However, this also increases the risk of rapid fire spread in coastal areas due to the dry vegetation.
While Santa Ana winds are less frequent in December compared to autumn, their potential impact remains significant. Their influence on temperature, humidity, fire risk, and air quality underscores the importance of understanding these powerful wind events when considering Los Angeles weather in December. Predicting the timing and intensity of Santa Ana winds is crucial for effective fire prevention and public safety measures. Their presence adds a dynamic element to the December climate, highlighting the region’s diverse weather patterns.
Frequently Asked Questions
This section addresses common inquiries regarding Los Angeles weather in December, providing concise and informative responses.
Question 1: How much rain is expected in Los Angeles during December?
December falls within Los Angeles’s wetter season. Average rainfall totals around 2-3 inches, although this can vary significantly year to year. Consulting specific weather forecasts closer to the date provides more accurate precipitation predictions.
Question 2: Is it cold in Los Angeles in December?
Los Angeles experiences mild winters. December temperatures typically range from the mid-50s to high 60s Fahrenheit (12-20C). While evenings can be cool, daytime temperatures are generally comfortable.
Question 3: What should I pack for a trip to Los Angeles in December?
Packing layers is recommended. Light jackets, sweaters, and long-sleeved shirts are suitable for cooler evenings and mornings. Rain gear is advisable due to the possibility of rainfall. Comfortable walking shoes are essential for exploring the city.
Question 4: Can I swim in the ocean in Los Angeles in December?
Ocean temperatures in December are cooler, typically in the low 60s Fahrenheit (15-17C). While some individuals may find swimming comfortable, water temperatures are considerably lower than during summer months. Wetsuits are recommended for extended water activities.
Question 5: Does it snow in Los Angeles in December?
Snowfall within the city of Los Angeles is extremely rare. However, the nearby San Gabriel Mountains often receive snowfall, providing opportunities for winter sports. Mountain road conditions can be hazardous during and after snow events, requiring appropriate precautions.
Question 6: Are Santa Ana winds common in December?
While Santa Ana winds are more prevalent in the fall, they can occur in December. These dry, downslope winds can significantly increase temperatures and decrease humidity, elevating fire risk. Monitoring weather forecasts for Santa Ana wind advisories is crucial for safety and preparedness.
Understanding these key aspects of Los Angeles weather in December allows for informed planning and a more enjoyable experience. Consulting up-to-date weather forecasts closer to specific travel dates provides the most accurate and relevant information.
The following sections will delve deeper into specific activities and recommendations for experiencing Los Angeles in December.
Tips for Navigating Los Angeles Weather in December
Careful planning enhances experiences in Los Angeles during December. The following tips address key aspects of navigating the region’s weather conditions during this period.
Tip 1: Layered Clothing is Essential: December temperatures can fluctuate throughout the day. Packing layers allows adaptation to changing conditions. Combining lighter garments with heavier outerwear provides flexibility and comfort.
Tip 2: Be Prepared for Rain: Rainfall is possible in December. Carrying a compact umbrella or waterproof jacket ensures preparedness for unexpected showers. Checking weather forecasts before venturing out provides additional guidance.
Tip 3: Monitor Mountain Weather Conditions: Individuals planning trips to the nearby mountains should monitor weather forecasts closely. Snowfall can impact road conditions and accessibility. Carrying chains and ensuring vehicles are properly equipped for winter driving is essential.
Tip 4: Consider Coastal Microclimates: Coastal areas can experience cooler temperatures and fog. Packing layers and wind-resistant clothing enhances comfort in these microclimates. Checking local coastal forecasts provides specific guidance.
Tip 5: Stay Hydrated: Even during cooler months, hydration remains important. Carrying a water bottle and refilling it throughout the day supports well-being, particularly during outdoor activities.
Tip 6: Check for Santa Ana Wind Advisories: Santa Ana winds can impact December weather. Monitoring weather forecasts for Santa Ana wind advisories provides awareness of potential fire risks and allows for appropriate precautions.
Tip 7: Utilize Public Transportation: Los Angeles offers diverse public transportation options. Utilizing public transport can mitigate parking challenges and reduce traffic congestion, particularly during peak season.
Tip 8: Book Accommodations and Tours in Advance: December can be a busy travel period. Booking accommodations and tours in advance secures preferred options and avoids potential availability limitations.
Observing these tips allows visitors and residents to navigate Los Angeles weather in December effectively. Preparedness contributes significantly to comfort and safety, enabling full enjoyment of the region’s offerings during this unique time of year.
The following conclusion synthesizes key information regarding Los Angeles weather in December and offers final recommendations.
Conclusion
Los Angeles in December offers a unique blend of mild weather, occasional rainfall, and the potential for diverse experiences. Temperatures generally range from the mid-50s to high 60s Fahrenheit (12-20C), creating comfortable conditions for outdoor exploration. Rainfall probability introduces an element of unpredictability, emphasizing the importance of preparedness. Coastal regions experience moderating influences from the Pacific Ocean, while nearby mountains offer opportunities to witness snowfall and engage in winter recreation. Factors such as sunshine hours, humidity levels, ocean temperatures, and the potential for Santa Ana winds contribute to the complexity of December weather patterns. Understanding these elements provides valuable context for planning activities and navigating the region effectively.
Preparation and awareness enhance experiences in Los Angeles during December. Adaptability to fluctuating weather conditions ensures comfort and safety. Monitoring forecasts provides crucial real-time information, allowing informed decision-making. Recognizing the interplay of various meteorological factors contributes to a deeper appreciation of the region’s dynamic climate and facilitates informed engagement with the unique characteristics of Los Angeles weather in December.
