January weather forecastOceanside, CA

January
Weather in January
January, the same as December, is another refreshing winter month in Oceanside, California, with an average temperature varying between 50.7°F (10.4°C) and 64°F (17.8°C).Temperature
With the onset of January, the average high-temperature registers at a still refreshing 64°F (17.8°C), subtly different from December's 62.4°F (16.9°C). Oceanside's nighttime temperature in January drops to an average of 50.7°F (10.4°C).Humidity
In January, the average relative humidity in Oceanside is 61%.Rainfall
In Oceanside, during January, the rain falls for 6 days and regularly aggregates up to 1.26" (32mm) of precipitation. Throughout the year, in Oceanside, California, there are 68.2 rainfall days, and 9.49" (241mm) of precipitation is accumulated.Ocean temperature
January and February, with an average ocean temperature of 58.6°F (14.8°C), are months with the coldest seawater.Note: Swimming in 58.6°F (14.8°C) is considered life-threatening. Even a few minutes in 55.4°F (13°C) water is uncomfortable, and swimming below 50°F (10°C) may cause total loss of breathing control and cold shock, depending on a person's physique.
Daylight
In January, the average length of the day in Oceanside is 10h and 15min.On the first day of January, sunrise is at 6:52 am and sunset at 4:53 pm. On the last day of the month, sunrise is at 6:45 am and sunset at 5:20 pm PST.
Sunshine
The average sunshine in January in Oceanside is 6.8h.UV index
The months with the lowest UV index are January through March, November and December, with an average maximum UV index of 4. A UV Index estimate of 3 to 5 represents a moderate health risk from exposure to the Sun's UV rays for the average person.Note: The UV index of 4 in January translates into these instructions:
Be vigilant - Preventing sunburn is recommended. The solar radiation is most powerful near the mid-day, so the exposure to the direct Sun should be reduced accordingly. A hat with a broad brim is indispensable, filtering out up to half of UV rays.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in January
Oceanside, CA
- Average high temperature in January: 64°F
The warmest month (with the highest average high temperature) is August (78.6°F).
The month with the lowest average high temperature is December (62.4°F).
- Average low temperature in January: 50.7°F
The month with the highest average low temperature is August (64.2°F).
The coldest month (with the lowest average low temperature) is February (49.6°F).
Average pressure in January
Oceanside, CA
- Average pressure in January: 30.09"Hg
The month with the highest atmospheric pressure is January (30.09"Hg).
The months with the lowest atmospheric pressure are June and September (29.88"Hg).
Average wind speed in January
Oceanside, CA
- Average wind speed in January: 5.1mph
The windiest months (with the highest average wind speed) are April and May (6mph).
The calmest month (with the lowest average wind speed) is October (4.8mph).
Average humidity in January
Oceanside, CA
- Average humidity in January: 61%
The month with the highest relative humidity is June (73%).
The month with the lowest relative humidity is November (60%).
Average rainfall in January
Oceanside, CA
- Average rainfall in January: 1.26"
The wettest month (with the highest rainfall) is December (1.97").
The driest month (with the least rainfall) is June (0.12").
Average rainfall days in January
Oceanside, CA
- Average rainfall days in January: 6 days
The month with the highest number of rainy days is March (8 days).
The month with the least rainy days is June (2.7 days).
Average sea temperature in January
Oceanside, CA
- Average sea temperature in January: 58.7°F
The best month for swimming (with the highest average sea temperature) is August (68°F).
The coldest months (with the lowest average sea temperature) are January and February (58.7°F).
Average daylight in January /
Average sunshine in January
Oceanside, CA
- Average daylight in January: 10h and 18min
The month with the longest days is June (Average daylight: 14h and 18min).
The month with the shortest days is December (Average daylight: 10h and 0min).
- Average sunshine in January: 6h and 48min
The months with the most sunshine are July and August (Average sunshine: 12h and 0min).
The month with the least sunshine is December (Average sunshine: 6h and 36min).
Average sunshine days in January
Oceanside, CA
- Average sunshine days in January: 23.8 days
The month with the most sunshine days is October (24.2 days).
The month with the least sunshine days is February (20 days).
Average UV index in January
Oceanside, CA
- Average UV index in January: 4
The months with the highest UV index are July, August and September (UV index 6).
The months with the lowest UV index are January, February, March, November and December (UV index 4).
Average cloud cover in January
Oceanside, CA
- Average cloud cover in January: 22
The month with the most cloud cover is December (Cloud cover 25).
The month with the least cloud cover is August (Cloud cover 8).
Average visibility in January
Oceanside, CA
- Average visibility in January: 6mi
The months with the highest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).
The months with the lowest visibility are January, February, March, April, May, June, July, August, September, October, November and December (6mi).





