August weather forecastYountville, CA
August
Weather in August
The last month of the summer, August, is another hot month in Yountville, California, with temperature in the range of an average low of 55.4°F (13°C) and an average high of 86.2°F (30.1°C).Temperature
Yountville, California, starts August with an average high-temperature of a still hot 86.2°F (30.1°C), a minor shift from July's 86.5°F (30.3°C). The month of August sees a significant daily temperature drop, recording an average low-temperature of 55.4°F (13°C).Heat index
Throughout August, the heat index is appraised at a hot 91.4°F (33°C). Take additional safety steps, risk of heat exhaustion and heat cramps is notable. Prolonged activity may cause heatstroke.It is noted that heat index values are ascertained for locations in the shade and with gentle breezes. Heat index values can rise by 15 Fahrenheit (8 Celsius) degrees when in direct sunlight.
Note: The heat index, also known as 'felt air temperature' or 'feels like', represents the fusion of temperature and moisture in the air to suggest how warm it feels. The individual's impression of temperature can be shaped by additional aspects such as metabolic variations, physical activity, and clothing. In the direct sunlight, the weather's impact can be amplified, possibly boosting the heat index by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are highly important for children. Young ones generally face higher dangers than adults since they sweat less. Along with their large skin surface area compared totheir small bodies and increased heat production from their activities, the risks are heightened.
Humidity
The average relative humidity in August is 59%.Rainfall
The months with the least rainfall are July and August Rain falls for 0.9 days and accumulates 0.04" (1mm) of rain.Daylight
The average length of the day in August is 13h and 37min.On the first day of the month, sunrise is at 6:12 am and sunset at 8:19 pm. On the last day of August, sunrise is at 6:38 am and sunset at 7:40 pm PDT.
Sunshine
In Yountville, the average sunshine in August is 11.9h.UV index
The months with the highest UV index are June through August, with an average maximum UV index of 6. A UV Index value of 6 to 7 symbolizes a high threat to health from exposure to the Sun's UV radiation for average individuals.Note: In August, the average maximum UV index of 6 translates into the following recommendations:
Enforce precautions and stick to sun safety measures. Preservation from skin and eye damage is essential. Between 10 a.m. and 4 p.m., the Sun's UV radiation is at its peak. Limit your exposure to direct sunlight during these hours. Limit sun-induced ocular harm with sunglasses that feature UVA and UVB filtration.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in August
Yountville, CA
- Average high temperature in August: 86.2°F
The warmest month (with the highest average high temperature) is July (86.5°F).
The month with the lowest average high temperature is December (54.5°F).
- Average low temperature in August: 55.4°F
The month with the highest average low temperature is August (55.4°F).
The coldest month (with the lowest average low temperature) is December (40.1°F).
Average pressure in August
Yountville, CA
- Average pressure in August: 29.91"Hg
The month with the highest atmospheric pressure is January (30.14"Hg).
The months with the lowest atmospheric pressure are June and August (29.91"Hg).
Average wind speed in August
Yountville, CA
- Average wind speed in August: 5mph
The windiest month (with the highest average wind speed) is May (6mph).
The calmest month (with the lowest average wind speed) is November (4.3mph).
Average humidity in August
Yountville, CA
- Average humidity in August: 59%
The month with the highest relative humidity is March (76%).
The month with the lowest relative humidity is September (54%).
Average rainfall in August
Yountville, CA
- Average rainfall in August: 0.04"
The wettest month (with the highest rainfall) is February (3.43").
The driest months (with the least rainfall) are July and August (0.04").
Average rainfall days in August
Yountville, CA
- Average rainfall days in August: 0.9 days
The month with the highest number of rainy days is March (13.9 days).
The month with the least rainy days is August (0.9 days).
Average daylight in August /
Average sunshine in August
Yountville, CA
- Average daylight in August: 13h and 36min
The month with the longest days is June (Average daylight: 14h and 48min).
The month with the shortest days is December (Average daylight: 9h and 30min).
- Average sunshine in August: 11h and 54min
The month with the most sunshine is July (Average sunshine: 12h and 0min).
The month with the least sunshine is December (Average sunshine: 5h and 36min).
Average sunshine days in August
Yountville, CA
- Average sunshine days in August: 29.3 days
The month with the most sunshine days is July (29.4 days).
The month with the least sunshine days is March (15.8 days).
Average UV index in August
Yountville, CA
- Average UV index in August: 6
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 August
Yountville, CA
- Average cloud cover in August: 7
The month with the most cloud cover is March (Cloud cover 40).
The month with the least cloud cover is July (Cloud cover 6).
Average visibility in August
Yountville, 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).
