January weather forecast
California, USA

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. In areas like Mammoth Lakes in the Sierra Nevada mountains, temperatures can plummet to an average low of 15°F (-9.4°C), making it one of the coldest spots in the state. Snowfall is common in these regions and can be heavy, often exceeding the amounts seen in December.

In contrast, Death Valley, located in the eastern desert region, remains relatively warm even in January. However, nights can still be chilly, reflecting the general cooling trend seen across the state at this time of year.

January is also a month when rainfall is prevalent, especially in the northern parts of the state. It may be considered one of the rainiest months, particularly in regions lying west of the mountain ranges, as these areas receive more rain than the eastern parts that lie in the rain shadow region.

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• Los Angeles - January »
  The months with the lowest UV index in Los Angeles, California, are January, February, November and December, with an average maximum UV index of 4. In Los Angeles in January, during 5.2 rainfall days, 1.69" (43mm) of precipitation is typically accumulated.
• San Francisco - January »
  January, February, November and December, with an average maximum UV index of 3, are months with the lowest UV index in San Francisco, California. In San Francisco in January, it is raining for 8.2 days, with typically 1.02" (26mm) of accumulated precipitation.
• San Diego - January »
  In San Diego during January, the rain falls for 5.3 days and regularly aggregates up to 1.06" (27mm) of precipitation. The months with the lowest UV index in San Diego are January through March, November and December, with an average maximum UV index of 4.
• San Jose - January »
  January, February, November and December, with an average maximum UV index of 3, are months with the lowest UV index in San Jose, California. On the last day of January, in San Jose, sunrise is at 7:11 am and sunset at 5:30 pm PST.
• Sacramento - January »
  On the first day of January sunrise is at 7:23 am and sunset at 4:55 pm. On the first day of January in Sacramento, sunrise is at 7:23 am and sunset at 4:55 pm.
• Fresno - January »
  On the first day of January in Fresno sunrise is at 7:11 am and sunset at 4:53 pm. In Fresno, California, in January, during 6.8 rainfall days, 1.42" (36mm) of precipitation is typically accumulated.
• Long Beach - January »
  January, February and December, with an average of 6.8h of sunshine, are months with the least sunshine in Long Beach. With an average ocean temperature of 58.3°F (14.6°C), January is the month with the coldest seawater in Long Beach.
• Oakland - January »
  In Oakland during January, the rain falls for 6.2 days and regularly aggregates up to 0.47" (12mm) of precipitation. January, February, November and December, with an average maximum UV index of 3, are months with the lowest UV index in Oakland.
• Bakersfield - January »
  The months with the least sunshine in Bakersfield are January and December, with an average of 6.7h of sunshine. January and December, with an average of 6.7h of sunshine, are months with the least sunshine in Bakersfield, California.
• Anaheim - January »
  The months with the lowest UV index in Anaheim, California, are January, February, November and December, with an average maximum UV index of 4. January, February, November and December, with an average maximum UV index of 4, are months with the lowest UV index in Anaheim.
• Santa Ana - January »
  On the last day of January, in Santa Ana sunrise is at 6:48 am and sunset at 5:21 pm PST. The months with the lowest UV index in Santa Ana are January, February, November and December, with an average maximum UV index of 4.
• Riverside - January »
  In Riverside snow does not fall in January, March through December. On the last day of January, in Riverside, California, sunrise is at 6:46 am and sunset at 5:19 pm PST.