Contents
- Weather in January
- Frequently asked questions
- Average temperature in January
- Average pressure in January
- Average wind speed in January
- Average humidity in January
- Average rainfall in January
- Average rainfall days in January
- Average daylight in January
- Average sunshine in January
- Average sunshine days in January
- Average UV index in January
- Average cloud cover in January
- Average visibility in January
Weather in January
Temperature
As December transitions into January, the average high-temperature rests at a still comfortable 65.5°F (18.6°C), maintaining a close resemblance to the previous month. During January, San Ysidro witnesses a consistent average low-temperature of 50.9°F (10.5°C).Humidity
The average relative humidity in January is 56%.Rainfall
In January, the rain falls for 5.1 days. Throughout January, 0.79" (20mm) of precipitation is accumulated. Throughout the year, there are 57.8 rainfall days, and 7.28" (185mm) of precipitation is accumulated.Daylight
In January, the average length of the day is 10h and 18min.On the first day of January, sunrise is at 6:49 am and sunset at 4:53 pm. On the last day of the month, sunrise is at 6:43 am and sunset at 5:19 pm PST.
Sunshine
In January, the average sunshine is 6.8h.UV index
The months with the lowest UV index are January, February, November and December, with an average maximum UV index of 4. A UV Index of 3 to 5 symbolizes a moderate threat to health from exposure to the Sun's UV radiation for the ordinary person.Note: In January, the maximum UV index of 4 transforms into these recommendations:
Guard yourself - Precautionary measures against sun damage are advocated. The midday Sun can be harmful due to its potent UV radiation; seek shade and reduce exposure. A wide-brimmed hat is a shield, deflecting up to 50% of harmful UV radiation from eyes.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What is the average January temperature?
What is the average humidity in January?
How much does it rain in January?
How many hours of daylight does San Ysidro have in January?
When are sunrise and sunset in January?
How long on average sun shines in January in San Ysidro?
What are the months with the lowest UV index?
What is the UV index intensity in January?
Average temperature in January
San Ysidro, CA
- Average high temperature in January: 65.5°F
The warmest month (with the highest average high temperature) is August (81.1°F).
The month with the lowest average high temperature is December (64°F).
- Average low temperature in January: 50.9°F
The month with the highest average low temperature is August (66.7°F).
The coldest month (with the lowest average low temperature) is February (50.2°F).
Average pressure in January
San Ysidro, CA
- Average pressure in January: 30.08"Hg
The month with the highest atmospheric pressure is January (30.08"Hg).
The months with the lowest atmospheric pressure are June, August and September (29.88"Hg).
Average wind speed in January
San Ysidro, CA
- Average wind speed in January: 5.2mph
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
San Ysidro, CA
- Average humidity in January: 56%
The month with the highest relative humidity is May (68%).
The month with the lowest relative humidity is November (55%).
Average rainfall in January
San Ysidro, CA
- Average rainfall in January: 0.79"
The wettest month (with the highest rainfall) is February (1.5").
The driest month (with the least rainfall) is June (0.08").
Average rainfall days in January
San Ysidro, CA
- Average rainfall days in January: 5.1 days
The month with the highest number of rainy days is March (7.5 days).
The month with the least rainy days is June (1.8 days).
Average daylight in January /
Average sunshine in January
San Ysidro, CA
- Average daylight in January: 10h and 2min
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 6min).
- Average sunshine in January: 6h and 5min
The month with the most sunshine is July (Average sunshine: 12h and 0min).
The month with the least sunshine is December (Average sunshine: 6h and 36min).
Average sunshine days in January
San Ysidro, CA
- Average sunshine days in January: 24.9 days
The month with the most sunshine days is June (27.8 days).
The month with the least sunshine days is February (20.8 days).
Average UV index in January
San Ysidro, CA
- Average UV index in January: 4
The months with the highest UV index are June, July, August and September (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 4).
Average cloud cover in January
San Ysidro, CA
- Average cloud cover in January: 21
The months with the most cloud cover are March and December (Cloud cover 25).
The month with the least cloud cover is August (Cloud cover 8).
Average visibility in January
San Ysidro, 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).
San Ysidro, California, USA
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