August weather forecastUpland, CA
August
Weather in August
The last month of the summer, August, is another tropical month in Upland, California, with temperature in the range of an average high of 91°F (32.8°C) and an average low of 65.8°F (18.8°C).Temperature
During the warmest month, August, temperatures average a high of 91°F (32.8°C) and a low of 65.8°F (18.8°C).Heat index
For August, the heat index is calculated to be a tropical 93.2°F (34°C). Preventive measures are required to mitigate the risk of heat cramps and heat exhaustion. Continuous activity may precipitate heatstroke.Thinking about the heat index, one should account for its values in shaded areas with gentle breezes. Direct sunlight can potentially boost the heat index by 15 Fahrenheit (8 Celsius) degrees.
Note: The heat index, also known as 'feels like' or 'felt air temperature', determines the feeling of heat when you account for the relative humidity. An individual's perception of weather can be influenced by a variety of factors including metabolic differences, being pregnant, and their degree of physical exertion. Awareness of direct sun exposure is crucial as it has the potential to heighten the weather's effects, pushing up the heat index by 15 Fahrenheit (8 Celsius) degrees. Heat index values are extremely significant for children. Young ones often do not realize the necessity to rest and replenish their fluids. Thirst is a delayed indication of dehydration - keeping hydrated, particularly in prolonged physical activity, is crucial.
Humidity
The least humid month in Upland is August, with an average relative humidity of 42%.Rainfall
In Upland, in August, it is raining for 1.7 days, with typically 0.12" (3mm) of accumulated precipitation. Throughout the year, there are 49.6 rainfall days, and 7.8" (198mm) of precipitation is accumulated.Snowfall
In Upland, California, snow does not fall in January, March through December.Daylight
In Upland, the average length of the day in August is 13h and 23min.On the first day of the month, sunrise is at 6:02 am and sunset at 7:51 pm. On the last day of August, sunrise is at 6:24 am and sunset at 7:17 pm PDT.
Sunshine
In Upland, the average sunshine in August is 12h.UV index
July and August, with an average maximum UV index of 7, are months with the highest UV index. A UV Index of 6 to 7 symbolizes a high health vulnerability from exposure to the Sun's UV rays for the average person.Note: An average maximum UV index of 7 in August leads to these recommendations:
Shun overexposure. Protection from sun ravages is indispensable. The Sun emits the most powerful UV radiation between 10 a.m. and 4 p.m. Try to avoid direct sunlight during this period. Sunglasses providing both UVA and UVB protection are non-negotiable on sunlit days.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in August
Upland, CA
- Average high temperature in August: 91°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 August: 65.8°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 August
Upland, CA
- Average pressure in August: 29.88"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 August
Upland, CA
- Average wind speed in August: 4.7mph
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 August
Upland, CA
- Average humidity in August: 42%
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 August
Upland, CA
- Average rainfall in August: 0.12"
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 August
Upland, CA
- Average rainfall days in August: 1.7 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 August
Upland, CA
- Average snowfall days in August: 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 August /
Average sunshine in August
Upland, CA
- Average daylight in August: 13h and 24min
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 August: 12h 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 August
Upland, CA
- Average sunshine days in August: 26.8 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 August
Upland, CA
- Average UV index in August: 7
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 August
Upland, CA
- Average cloud cover in August: 5
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 August
Upland, CA
- Average visibility in August: 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).





