January weather forecastGilroy, CA

January
Weather in January
January, like December, is a moderate winter month in Gilroy, California, with an average temperature varying between 59.5°F (15.3°C) and 41.4°F (5.2°C).Temperature
Gilroy sees the arrival of January with an average high-temperature of a still mild 59.5°F (15.3°C), indicating a subtle variation from December. Gilroy throughout January, experiences an average nighttime temperature of 41.4°F (5.2°C).Humidity
The average relative humidity in January is 72%.Rainfall
In Gilroy, in January, during 5.5 rainfall days, 0.55" (14mm) of precipitation is typically accumulated. Throughout the year, there are 43.4 rainfall days, and 3.66" (93mm) of precipitation is accumulated.Daylight
In January, the average length of the day is 9h and 58min.On the first day of January, sunrise is at 7:19 am and sunset at 5:00 pm. On the last day of the month, sunrise is at 7:09 am and sunset at 5:29 pm PST.
Sunshine
The average sunshine in January is 6.4h.UV index
The months with the lowest UV index are January, February, November and December, with an average maximum UV index of 3. A UV Index of 3 to 5 symbolizes a moderate health risk from exposure to the Sun's UV radiation for the average person.Note: A maximum high daily UV index of 3 during January translates into the following directions:
Undertake precautions - Guarding against sun damage is counselled. Minimize direct exposure to the Sun during midday when its radiation is at its peak. Outfit yourself in sun-safe attire, like long sleeves, pants, a hat, and UV-blocking sunglasses.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in January
Gilroy, CA
- Average high temperature in January: 59.5°F
The warmest month (with the highest average high temperature) is August (85.1°F).
The month with the lowest average high temperature is December (57.6°F).
- Average low temperature in January: 41.4°F
The months with the highest average low temperature are August and September (54.1°F).
The coldest months (with the lowest average low temperature) are February and March (40.6°F).
Average pressure in January
Gilroy, CA
- Average pressure in January: 30.14"Hg
The month with the highest atmospheric pressure is January (30.14"Hg).
The months with the lowest atmospheric pressure are June, August and September (29.92"Hg).
Average wind speed in January
Gilroy, CA
- Average wind speed in January: 4mph
The windiest month (with the highest average wind speed) is May (5.3mph).
The calmest month (with the lowest average wind speed) is November (3.9mph).
Average humidity in January
Gilroy, CA
- Average humidity in January: 72%
The month with the highest relative humidity is March (74%).
The month with the lowest relative humidity is September (57%).
Average rainfall in January
Gilroy, CA
- Average rainfall in January: 0.55"
The wettest month (with the highest rainfall) is December (0.83").
The driest months (with the least rainfall) are June, July and August (0").
Average rainfall days in January
Gilroy, CA
- Average rainfall days in January: 5.5 days
The month with the highest number of rainy days is March (8.3 days).
The month with the least rainy days is August (0.6 days).
Average daylight in January /
Average sunshine in January
Gilroy, CA
- Average daylight in January: 10h and 0min
The month with the longest days is June (Average daylight: 14h and 42min).
The month with the shortest days is December (Average daylight: 9h and 42min).
- Average sunshine in January: 6h and 24min
The month with the most sunshine is July (Average sunshine: 12h and 6min).
The month with the least sunshine is December (Average sunshine: 6h and 0min).
Average sunshine days in January
Gilroy, CA
- Average sunshine days in January: 24.2 days
The month with the most sunshine days is July (29.9 days).
The month with the least sunshine days is March (21.4 days).
Average UV index in January
Gilroy, CA
- Average UV index in January: 3
The months with the highest UV index are June, July and August (UV index 6).
The months with the lowest UV index are January, February, November and December (UV index 3).
Average cloud cover in January
Gilroy, CA
- Average cloud cover in January: 31
The month with the most cloud cover is March (Cloud cover 35).
The month with the least cloud cover is July (Cloud cover 7).
Average visibility in January
Gilroy, 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).





