Climate and monthly weather forecast
California, USA

California has a diverse climate ranging from a wet temperate rainforest in the north, hot, arid desert in the interior, snowy alpine in the mountains, and the warm Mediterranean in the rest of the state. The Pacific Ocean borders the western part of the state, Oregon the north, Arizona and Nevada the east, and Mexico the south. The state's varied topography covers the Pacific Ocean on the west coast to the Sierra Nevada mountain range in the east, and redwood forests in the north to the Mojave Desert in the south.

The climate ranges from polar to subtropical due to the large size of the state. Summer fog is regular on the coast due to the cold California current, while inland areas experience cold winters and hot summers. Proximity to the Pacific Ocean regulates summer temperatures of parts of Los Angeles and San Francisco near to the coast and creates different microclimates as downtowns of these cities experience hotter summer temperatures and colder winters.

Northern parts of California are rainier than the south, and the high mountain ranges influence the climate as western mountain slopes receive more rain than the eastern leeward parts that lie in the rain shadow region. The high mountains on the western side have an alpine climate, while those in the east have hot summers and cold winters. Death Valley, a desert on the eastern side, is the hottest location in the world with a recorded temperature of 134°F (56.7°C), while Boca has the lowest recorded temperature in the state of -45°F (-42.8°C).

The best time to visit many parts of California is during spring and autumn, while some are fine even in the peak of summer.
Mid-spring is a good time as the winter cold recedes, and the sun resumes duties in full glory. Western coastal regions like San Francisco experience mild and pleasant summer days in the 50°F (10°C) to 70°F (21.1°C) range. Up in the north, summers are comfortable without extremities of temperatures.
Autumn has mild temperatures, particularly in the central, eastern, and southern parts of the state, with a sprinkling of rain.
Generally, both spring and autumn tend to be less hot and humid than the summer in a majority of areas of California and are more pleasant.

Winter from December to February is the worst time to visit most of California as the state experiences cold and chilly weather.
Northern California, with its highlands and mountain ranges, is chilly as the higher altitudes accumulate large amounts of snow often up to 100" (2540mm). On the western side, the coastal areas around the Pacific Ocean are relatively warmer compared to the inland regions, but temperatures are low during the winter nights. The deserts in the south also tend to be cold during the winter nights.
Although there are a few areas in the state where summers are avoidable, usually winter is the most avoidable period in the majority of California.

Spring in California marks a transition from the cold of winter to warmer temperatures. During this time, the weather becomes damp and increasingly warm. Coastal regions enjoy mild temperatures, while inland areas begin to heat up. The spring season is also marked by the blossoming of various flowers, adding to the scenic beauty. Snow begins to melt in the mountainous regions, and the entire state welcomes the freshness of the new season.

Summer in California varies significantly across the state. Coastal areas such as the San Francisco region experience mild summers with an average high of 67°F (19.4°C) in August. Central and eastern parts, including cities like Sacramento and Fresno, witness hot summers with average high temperatures from 91°F (32.8°C) to 97°F (36.1°C). Summer fog is a prominent feature along the western coasts, whereas the eastern desert regions are extremely hot, particularly in places like Death Valley.

Autumn in California is characterized by mild temperatures, particularly in the central, eastern, and southern regions. Rainfall may occur, adding a freshness to the environment. Coastal areas continue to enjoy pleasant weather, while the inland regions cool down from the summer heat. The changing color of the leaves creates picturesque landscapes throughout the state, and temperatures are generally more pleasant compared to the peak of summer.

Winter brings cold and chilly weather across California. In the northern regions with highlands and mountain ranges, temperatures drop substantially, and large amounts of snow accumulate. Coastal areas around the Pacific Ocean are relatively warmer but still experience low temperatures, particularly during the nights. The southern deserts also cool down significantly during the winter nights. Frost is regular in various parts of the state, and winter low temperatures range from 40°F (4.4°C) to 50°F (10°C) in coastal areas, while places like Mammoth Lakes in the Sierra Nevada mountains freeze to an average low of 15°F (-9.4°C).

January is often the coldest month of the year in California, marking the peak of the winter season. In coastal areas, such as Los Angeles and San Francisco, temperatures range from 40°F (4.4°C) to 50°F (10°C). The weather is relatively warmer compared to the inland and mountainous regions but is still cooler compared to December. Northern parts of California, particularly in highland and mountainous regions, experience substantial cold. Weather in January »

February continues the winter season in California, with a gradual transition towards milder conditions. Coastal cities, including Los Angeles and San Francisco, experience temperatures slightly warmer than January, ranging from 45°F (7.2°C) to 55°F (12.8°C). Weather in February »

March heralds the onset of spring in California, bringing milder temperatures and a noticeable shift in weather patterns. Coastal areas such as Los Angeles and San Francisco continue to warm, with temperatures ranging from 50°F (10°C) to 60°F (15.6°C). Weather in March »

April continues the progression of spring in California, leading to more pleasant and temperate conditions throughout the state. Coastal areas such as Los Angeles and San Francisco experience a further warming, with temperatures ranging from 55°F (12.8°C) to 65°F (18.3°C). Weather in April »

May signifies the late spring season in California, exhibiting warmer temperatures and drier conditions. Coastal cities, including San Francisco and Los Angeles, experience further warming with temperatures ranging from 60°F (15.6°C) to 70°F (21.1°C). Weather in May »

June marks the beginning of summer in California, characterized by a noticeable increase in temperatures and continued dry conditions. Coastal areas like San Francisco and Los Angeles see temperatures ranging from 65°F (18.3°C) to 75°F (23.9°C). Weather in June »

July in California is characterized by the full embrace of summer, with hot temperatures across the state. Coastal regions like Los Angeles and San Francisco maintain a more moderate climate due to the proximity of the Pacific Ocean, with temperatures ranging from 70°F (21.1°C) to 80°F (26.7°C). Weather in July »

August continues the summer trend in California with warm temperatures and dry conditions, but subtle changes begin to emerge as the state approaches the end of the summer season. Coastal cities like San Francisco and Los Angeles maintain their moderate climate, with temperatures ranging from 70°F (21.1°C) to 80°F (26.7°C). Weather in August »

September marks the transition from summer to autumn in California, with weather changes that vary across the state. It's a month of mixed conditions, retaining some summer characteristics while beginning to show signs of the coming fall. In coastal regions such as San Francisco and Los Angeles, temperatures generally range from 65°F (18.3°C) to 75°F (23.9°C), remaining pleasant but starting to cool down slightly from the peak summer months. Inland areas and the Sierra Nevada mountains experience temperatures between 45°F (7.2°C) to 55°F (12.8°C). Weather in September »

October in California brings more distinct signs of autumn, with temperatures continuing to cool and subtle changes in precipitation patterns. The state's diverse climate zones lead to a variety of weather experiences during this month. In coastal regions such as San Francisco and Los Angeles, temperatures generally range from 60°F (15.6°C) to 70°F (21.1°C). Weather in October »

November in California signifies a deeper transition into autumn, with cooler temperatures across the state and more noticeable changes in precipitation patterns. Coastal areas such as San Francisco and Los Angeles experience temperatures ranging from 55°F (12.8°C) to 65°F (18.3°C), with cooler evenings. Weather in November »

December marks the beginning of the winter season in California, bringing cooler temperatures, increased precipitation, and in some areas, the onset of snowfall. Coastal areas like San Francisco and Los Angeles see temperatures ranging from 50°F (10°C) to 60°F (15.6°C). Weather in December »