August weather forecastSan Marcos, CA
August
Weather in August
The last month of the summer, August, is another warm month in San Marcos, California, with an average temperature fluctuating between 64.2°F (17.9°C) and 81.9°F (27.7°C).Temperature
The warmest period is August, when temperatures fluctuate between an average high of 81.9°F (27.7°C) and a low of 64.2°F (17.9°C).Heat index
For most parts of August, the heat index is computed to be 84.2°F (29°C). Exhaustion is likely with prolonged exposure and activity. Sustaining activity may result in heat cramps.Be informed that the heat index values are oriented around shady conditions and gentle breezes. Heat index values may surge by up to 15 Fahrenheit (8 Celsius) degrees in the presence of direct sunlight.
Note: The heat index, also known as 'feels like' or 'felt air temperature', blends air temperature and moisture content to represent the felt temperature to humans. This effect is subjective, differing among individuals based on their physical activity and perception of heat, which can be influenced by factors like wind, clothing, and metabolic variances. Keep in mind that direct sunshine exposure can amplify the weather's effects, possibly increasing the heat index by up to 15 Fahrenheit (8 Celsius) degrees. Heat index values are highly important for children. Young children are more at risk than adults since they tend to sweat less. Moreover, their large skin surface in proportion to their small bodies and the high heat production due to their activities contribute to their vulnerability.
Humidity
The average relative humidity in August in San Marcos is 63%.Rainfall
In San Marcos, California, in August, during 1.6 rainfall days, 0.12" (3mm) of precipitation is typically accumulated. In San Marcos, during the entire year, the rain falls for 52.1 days and collects up to 6.1" (155mm) of precipitation.Daylight
In August, the average length of the day is 13h and 20min.On the first day of the month, sunrise is at 6:02 am and sunset at 7:47 pm. On the last day of August, in San Marcos, sunrise is at 6:22 am and sunset at 7:14 pm PDT.
Sunshine
In August, the average sunshine is 12h.UV index
June through September, with an average maximum UV index of 6, are months with the highest UV index. A UV Index reading of 6 to 7 represents a high threat to health from exposure to the Sun's UV rays for the ordinary person.Note: In August, a regular UV index of 6 translates into these guidelines:
Exercise precautions and adapt sun safety practices. Defence against skin and eye affliction is paramount. Minimize exposure to direct sunlight and seek shade from 10 a.m. to 4 p.m., when UV radiation is most intense, but remember that shade structures may not offer complete protection. Consider a wide-brim hat essential for effective sun defense covering your face, neck, and eyes.
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature in August
San Marcos, CA
- Average high temperature in August: 81.9°F
The warmest month (with the highest average high temperature) is August (81.9°F).
The months with the lowest average high temperature are February and December (63.3°F).
- Average low temperature in August: 64.2°F
The month with the highest average low temperature is August (64.2°F).
The coldest month (with the lowest average low temperature) is February (48°F).
Average pressure in August
San Marcos, CA
- Average pressure in August: 29.88"Hg
The month with the highest atmospheric pressure is January (30.09"Hg).
The month with the lowest atmospheric pressure is June (29.87"Hg).
Average wind speed in August
San Marcos, CA
- Average wind speed in August: 4.7mph
The windiest month (with the highest average wind speed) is April (5.7mph).
The calmest month (with the lowest average wind speed) is October (4.4mph).
Average humidity in August
San Marcos, CA
- Average humidity in August: 63%
The month with the highest relative humidity is May (70%).
The month with the lowest relative humidity is November (56%).
Average rainfall in August
San Marcos, CA
- Average rainfall in August: 0.12"
The wettest month (with the highest rainfall) is December (1.22").
The driest month (with the least rainfall) is June (0.08").
Average rainfall days in August
San Marcos, CA
- Average rainfall days in August: 1.6 days
The month with the highest number of rainy days is March (7.8 days).
The month with the least rainy days is June (1.2 days).
Average daylight in August /
Average sunshine in August
San Marcos, CA
- Average daylight in August: 13h and 18min
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 0min).
- Average sunshine in August: 12h and 0min
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 48min).
Average sunshine days in August
San Marcos, CA
- Average sunshine days in August: 25.8 days
The month with the most sunshine days is August (25.8 days).
The month with the least sunshine days is February (20 days).
Average UV index in August
San Marcos, CA
- Average UV index in August: 6
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, March, November and December (UV index 4).
Average cloud cover in August
San Marcos, CA
- Average cloud cover in August: 7
The months with the most cloud cover are March and December (Cloud cover 23).
The month with the least cloud cover is August (Cloud cover 7).
Average visibility in August
San Marcos, 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).
