San Diego Weather in August

August is the pinnacle of summer weather for San Diego, California. Overall, this is the city's hottest and driest month.

This page gives detailed information on the typical August temperature, precipitation, sun, humidity, wind and storms for San Diego.

The numbers here are historical averages based on climate data gathered at the San Diego International Airport, located on San Diego Bay near the city center.

Temperature Weather iconTemperature

76 °F August average high 25 °C
67 °F August average low 19 °C

In most years, San Diego averages a daily maximum temperature for August that's between 74 and 79 degrees Fahrenheit (23 to 26 degrees Celsius). The minimum temperature usually falls between 65 and 69 °F (18 to 20 °C).

August is San Diego's hottest month overall, with temperatures peaking on the 27th. That date has daily highs averaging 77.0 °F (25.0 °C) and lows of 66.7 °F (19.3 °C).

30 days 70 °F max. or more (21 °C)
27 days 70 °F min. or less (21 °C)

Nearly every day in August warms to over 70 °F (21 °C) in San Diego. The city averages 6 days this month when the thermometer reaches into the 80s °F (over 26 °C). Temperatures above 90 °F (32 °C) occur in August about once a decade.

August does not normally get as cold as 60 °F (16 °C).

Rainy Weather iconRain

0.02 in total precipitation 0.5 mm
0 days of rain

August is San Diego's driest month. Most years, San Diego has no rain in August. Just one in every four years receives 0.01 inches (0.3 mm) or more precipitation.

Sunny Weather iconSun

70 % sunshine
15 days clear skies

The sun's rays reach the ground in San Diego during 70 percent of daylight hours on average in August, for a total of 288 hours in the month. Typically on 15 days this month the sky is mainly clear, with at most 30 percent cloud cover.

Sunlight in August at San Diego lasts for 13 hours and 18 minutes a day on average. The longest day of the month is the 1st with 13 hours and 44 minutes of daylight. By the end of the month, the days have shortened to 12:51 from sunrise to sunset. These durations can vary by a minute or two from year to year.

Humid Weather iconHumidity

74 % August average humidity

The relative humidity in San Diego during August usually peaks at 81 percent in the morning then drops to 64 percent by early afternoon.

Local Time1 am4 am7 am10 am1 pm4 pm7 pm10 pm
Humidity % 80 81 79 68 64 66 76 79

Windy Weather iconWind

7.4 mph August wind speed average 11.9 kph

August is a little windier than most other months in San Diego.

Stormy Weather iconStorms

0 days rainfall of 0.5 inches (13 mm) or more
0 days with thunderstorms in August

San Diego has a thunderstorm during August about once every three or four years.


These weather data are long-term historical averages provided by the National Climatic Data Center of the United States. The temperature and precipitation numbers are 1981-2010 normals while the humidity and thunderstorm statistics are 1961-1990 normals.

San Diego Weather
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