San Diego Weather in May

May has some of the year's cloudiest weather at San Diego, California. Yet it is a month with little rain.

This page gives detailed information on the typical May 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

70 °F May average high 21 °C
60 °F May average low 16 °C
12 days 70 °F max. or more (21 °C)
18 days 60 °F min. or less (16 °C)

Every day in May warms to over 60 degrees Fahrenheit (16 degrees Celsius) in San Diego. The city averages 1 day this month when the thermometer reaches into the 80s °F (over 26 °C), although days that hot don't happen every year. Temperatures above 90 °F (32 °C) can occur some years during May.

May does not normally get any colder than 50 °F (40 °C).

Rainy Weather iconRain

0.3 in total precipitation 7 mm
2 days of rain

Most years, San Diego gets less than 0.3 inches (9 mm) of rain in May. About once every four years, the city receives no rain at all this month.

Sunny Weather iconSun

59 % sunshine
8 days clear skies

The sun's rays reach the ground in San Diego during 59 percent of daylight hours on average in May, for a total of 254 hours in the month. Typically on 8 days this month the sky is mainly clear, with at most 30 percent cloud cover. May has fewer clear days than other months.

Sunlight in May at San Diego lasts for 13 hours and 51 minutes a day on average. The shortest day of the month is the 1st with 13 hours and 29 minutes of daylight. By the end of the month, the days have lengthened to 14:10 from sunrise to sunset. These durations can vary by a minute or two from year to year.

Humid Weather iconHumidity

71 % May average humidity

The relative humidity in San Diego during May usually peaks at 77 percent just after midnight then drops to 61 percent by early afternoon.

Local Time1 am4 am7 am10 am1 pm4 pm7 pm10 pm
Humidity % 77 77 74 65 61 64 72 75

Windy Weather iconWind

7.9 mph May wind speed average 12.7 kph

May is the windiest month of the year at San Diego.

Stormy Weather iconStorms

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

May averages just one thunderstorm a decade.


The weather data here are long-term averages provided by the US National Centers for Environmental Information (NCEI). Temperature and precipitation are 1991-2020 normals while humidity and thunderstorms are 1961-1990 normals.

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