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 snowfall 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
At the onset of January, Ontario records an average high-temperature of a still enjoyable 64.6°F (18.1°C), showing little deviation from the preceding month. Ontario records an average low-temperature of 46.8°F (8.2°C) throughout the month of January.Humidity
The average relative humidity in January in Ontario is 49%.Rainfall
In Ontario, California, in January, it is raining for 5.4 days, with typically 1.18" (30mm) of accumulated precipitation. In Ontario, during the entire year, the rain falls for 49.6 days and collects up to 7.8" (198mm) of precipitation.Snowfall
In Ontario, California, snow does not fall in January, March through December.Daylight
The average length of the day in January is 10h and 11min.On the first day of January in Ontario, sunrise is at 6:56 am and sunset at 4:52 pm. On the last day of the month, sunrise is at 6:48 am and sunset at 5:19 pm PST.
Sunshine
The average sunshine in January in Ontario, California, is 7h.UV index
In January, the average daily maximum UV index in Ontario is 4. A UV Index of 3 to 5 symbolizes a moderate threat to health from exposure to the Sun's UV rays for the ordinary person.Note: The daily high UV index of 4 during January translates into the following recommendations:
Prioritize safety - Recommendations to avert sunburn are shared. When the Sun is at its strongest around midday, find shade and limit exposure. A hat with a generous brim can prevent nearly 50% of UV rays from reaching your eyes.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
What is the usual temperature for Ontario in January?
What is the average humidity in January in Ontario?
How many days does it rain in January in Ontario?
When it does not snow in Ontario?
Does it snow in Ontario in January?
What is the average length of the day in January in Ontario?
When are sunrise and sunset in January in Ontario?
How long on average sun shines in January in Ontario?
What is the UV index reading in January in Ontario?
Average temperature in January
Ontario, CA
- Average high temperature in January: 64.6°F
The warmest month (with the highest average high temperature) is August (91°F).
The month with the lowest average high temperature is December (62.1°F).
- Average low temperature in January: 46.8°F
The month with the highest average low temperature is August (65.8°F).
The coldest month (with the lowest average low temperature) is December (45.5°F).
Average pressure in January
Ontario, CA
- Average pressure in January: 30.1"Hg
The month with the highest atmospheric pressure is January (30.1"Hg).
The month with the lowest atmospheric pressure is June (29.86"Hg).
Average wind speed in January
Ontario, CA
- Average wind speed in January: 5.3mph
The windiest months (with the highest average wind speed) are April and May (5.8mph).
The calmest month (with the lowest average wind speed) is September (4.4mph).
Average humidity in January
Ontario, CA
- Average humidity in January: 49%
The months with the highest relative humidity are March and May (54%).
The month with the lowest relative humidity is August (42%).
Average rainfall in January
Ontario, CA
- Average rainfall in January: 1.18"
The wettest month (with the highest rainfall) is February (1.77").
The driest month (with the least rainfall) is June (0.04").
Average rainfall days in January
Ontario, CA
- Average rainfall days in January: 5.4 days
The month with the highest number of rainy days is March (7.1 days).
The month with the least rainy days is June (1.2 days).
Average snowfall days in January
Ontario, CA
- Average snowfall days in January: 0 days
The month with the highest number of snowfall days is February (0.1 days).
The months with the least snowfall days are January, March, April, May, June, July, August, September, October, November and December (0 days).
Average daylight in January /
Average sunshine in January
Ontario, CA
- Average daylight in January: 10h and 1min
The month with the longest days is June (Average daylight: 14h and 24min).
The month with the shortest days is December (Average daylight: 9h and 54min).
- Average sunshine in January: 7h and 0min
The month with the most sunshine is July (Average sunshine: 12h and 6min).
The months with the least sunshine are February and December (Average sunshine: 6h and 54min).
Average sunshine days in January
Ontario, CA
- Average sunshine days in January: 24.6 days
The month with the most sunshine days is June (28.2 days).
The month with the least sunshine days is February (21.5 days).
Average UV index in January
Ontario, CA
- Average UV index in January: 4
The months with the highest UV index are July and August (UV index 7).
The month with the lowest UV index is December (UV index 3).
Average cloud cover in January
Ontario, CA
- Average cloud cover in January: 19
The month with the most cloud cover is December (Cloud cover 21).
The month with the least cloud cover is August (Cloud cover 5).
Average visibility in January
Ontario, 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).
Ontario, California, USA
Weather forecast for your location
2. Allow the app to use your location