1. WeatherSpark.com
  2. United States
  3. California
  4. San Diego

Summer Weather in San Diego California, United States

Daily high temperatures increase by 8°F, from 69°F to 77°F, rarely falling below 66°F or exceeding 83°F. The highest daily average high temperature is 77°F on August 26.

Daily low temperatures increase by 6°F, from 62°F to 68°F, rarely falling below 58°F or exceeding 72°F. The highest daily average low temperature is 68°F on August 25.

For reference, on August 26, the hottest day of the year, temperatures in San Diego typically range from 68°F to 77°F, while on December 28, the coldest day of the year, they range from 50°F to 65°F.

Average High and Low Temperature in the Summer in San Diego

Average High and Low Temperature in the Summer in San DiegoJunJulAug55°F55°F60°F60°F65°F65°F70°F70°F75°F75°F80°F80°F85°F85°FSpringFallAug 2677°FAug 2677°F68°F68°FJun 169°FJun 169°F62°F62°FJul 174°FJul 174°F65°F65°FAug 176°FAug 176°F68°F68°F
The daily average high (red line) and low (blue line) temperature, with 25th to 75th and 10th to 90th percentile bands. The thin dotted lines are the corresponding average perceived temperatures.

The figure below shows you a compact characterization of the hourly average summer temperatures. The horizontal axis is the day, the vertical axis is the hour of the day, and the color is the average temperature for that hour and day.

Average Hourly Temperature in the Summer in San Diego

Average Hourly Temperature in the Summer in San DiegoJunJulAug12 AM12 AM2 AM2 AM4 AM4 AM6 AM6 AM8 AM8 AM10 AM10 AM12 PM12 PM2 PM2 PM4 PM4 PM6 PM6 PM8 PM8 PM10 PM10 PM12 AM12 AMSpringFallcoolcoolcomfortablewarm
frigid 15°F freezing 32°F very cold 45°F cold 55°F cool 65°F comfortable 75°F warm 85°F hot 95°F sweltering
The average hourly temperature, color coded into bands. The shaded overlays indicate night and civil twilight.

Casablanca, Morocco (5,969 miles away) and Mossel Bay, South Africa (10,115 miles) are the far-away foreign places with temperatures most similar to San Diego (view comparison).

Map
Marker
© OpenStreetMap contributors

Compare San Diego to another city:

Map

The summer in San Diego experiences decreasing cloud cover, with the percentage of time that the sky is overcast or mostly cloudy decreasing from 21% to 10%.

The clearest day of the summer is August 31, with clear, mostly clear, or partly cloudy conditions 90% of the time.

For reference, on February 20, the cloudiest day of the year, the chance of overcast or mostly cloudy conditions is 43%, while on September 10, the clearest day of the year, the chance of clear, mostly clear, or partly cloudy skies is 91%.

Cloud Cover Categories in the Summer in San Diego

Cloud Cover Categories in the Summer in San DiegoJunJulAug0%100%10%90%20%80%30%70%40%60%50%50%60%40%70%30%80%20%90%10%100%0%SpringFallJun 179%Jun 179%Aug 3190%Aug 3190%Jul 189%Jul 189%Aug 186%Aug 186%clearmostly clearpartly cloudyovercast
0% clear 20% mostly clear 40% partly cloudy 60% mostly cloudy 80% overcast 100%
The percentage of time spent in each cloud cover band, categorized by the percentage of the sky covered by clouds.

A wet day is one with at least 0.04 inches of liquid or liquid-equivalent precipitation. In San Diego, the chance of a wet day over the course of the summer is essentially constant, remaining around 2% throughout.

For reference, the year's highest daily chance of a wet day is 20% on February 22, and its lowest chance is 0% on June 27.

Probability of Precipitation in the Summer in San Diego

Probability of Precipitation in the Summer in San DiegoJunJulAug0.0%0.0%0.5%0.5%1.0%1.0%1.5%1.5%2.0%2.0%2.5%2.5%3.0%3.0%3.5%3.5%4.0%4.0%4.5%4.5%5.0%5.0%5.5%5.5%6.0%6.0%SpringFallJun 260%Jun 260%Jun 11%Jun 11%Aug 312%Aug 312%Aug 13%Aug 13%rain
The percentage of days in which various types of precipitation are observed, excluding trace quantities: rain alone, snow alone, and mixed (both rain and snow fell in the same day).

Rainfall

To show variation within the season and not just the monthly totals, we show the rainfall accumulated over a sliding 31-day period centered around each day.

The average sliding 31-day rainfall during the summer in San Diego is essentially constant, remaining about 0.1 inches throughout, and rarely exceeding 0.3 inches.

The lowest average 31-day accumulation is 0.0 inches on June 22.

Average Monthly Rainfall in the Summer in San Diego

Average Monthly Rainfall in the Summer in San DiegoJunJulAug0.0 in0.0 in0.2 in0.2 in0.4 in0.4 in0.6 in0.6 in0.8 in0.8 in1.0 in1.0 inSpringFallJun 220.0 inJun 220.0 inJun 10.1 inJun 10.1 inAug 310.1 inAug 310.1 inAug 10.1 inAug 10.1 in
The average rainfall (solid line) accumulated over the course of a sliding 31-day period centered on the day in question, with 25th to 75th and 10th to 90th percentile bands. The thin dotted line is the corresponding average snowfall.

Over the course of the summer in San Diego, the length of the day is rapidly decreasing. From the start to the end of the season, the length of the day decreases by 1 hour, 18 minutes, implying an average daily decrease of 51 seconds, and weekly decrease of 6 minutes, 0 seconds.

The shortest day of the summer is August 31, with 12 hours, 52 minutes of daylight and the longest day is June 21, with 14 hours, 19 minutes of daylight.

Hours of Daylight and Twilight in the Summer in San Diego

Hours of Daylight and Twilight in the Summer in San DiegoJunJulAug0 hr24 hr4 hr20 hr8 hr16 hr12 hr12 hr16 hr8 hr20 hr4 hr24 hr0 hrSpringFallJun 2114 hr, 18 minJun 2114 hr, 18 minnightnightdaydayAug 3112 hr, 52 minAug 3112 hr, 52 minAug 113 hr, 44 minAug 113 hr, 44 min
The number of hours during which the Sun is visible (black line). From bottom (most yellow) to top (most gray), the color bands indicate: full daylight, twilight (civil, nautical, and astronomical), and full night.

The earliest sunrise of the summer in San Diego is 5:40 AM on June 12 and the latest sunrise is 42 minutes later at 6:22 AM on August 31.

The latest sunset is 8:00 PM on June 29 and the earliest sunset is 46 minutes earlier at 7:14 PM on August 31.

Daylight saving time is observed in San Diego during 2023, but it neither starts nor ends during the summer, so the entire season is in daylight saving time.

For reference, on June 21, the longest day of the year, the Sun rises at 5:41 AM and sets 14 hours, 19 minutes later, at 7:59 PM, while on December 22, the shortest day of the year, it rises at 6:47 AM and sets 10 hours, 0 minutes later, at 4:47 PM.

Sunrise & Sunset with Twilight in the Summer in San Diego

Sunrise & Sunset with Twilight in the Summer in San DiegoJunJulAug2 AM4 AM6 AM8 AM10 AM12 PM2 PM4 PM6 PM8 PM10 PM12 AMSpringFall5:40 AM5:40 AMJun 127:56 PMJun 127:56 PM6:22 AM6:22 AMAug 317:14 PMAug 317:14 PM5:44 AM5:44 AMJul 18:00 PMJul 18:00 PM6:02 AM6:02 AMAug 17:46 PMAug 17:46 PMSolarMidnightSolarMidnightSolarNoonSunriseSunset
The solar day in the summer. From bottom to top, the black lines are the previous solar midnight, sunrise, solar noon, sunset, and the next solar midnight. The day, twilights (civil, nautical, and astronomical), and night are indicated by the color bands from yellow to gray.

The figure below presents a compact representation of the sun's elevation (the angle of the sun above the horizon) and azimuth (its compass bearing) for every hour of every day in the reporting period. The horizontal axis is the day of the year and the vertical axis is the hour of the day. For a given day and hour of that day, the background color indicates the azimuth of the sun at that moment. The black isolines are contours of constant solar elevation.

Solar Elevation and Azimuth in the Summer in San Diego

Solar Elevation and Azimuth in the Summer in San DiegoJunJulAug12 AM12 AM2 AM2 AM4 AM4 AM6 AM6 AM8 AM8 AM10 AM10 AM12 PM12 PM2 PM2 PM4 PM4 PM6 PM6 PM8 PM8 PM10 PM10 PM12 AM12 AMSpringFall0010202030304050506060708000101020303040405060607070
northeastsouthwest
Solar elevation and azimuth in the the summer of 2023. The black lines are lines of constant solar elevation (the angle of the sun above the horizon, in degrees). The background color fills indicate the azimuth (the compass bearing) of the sun. The lightly tinted areas at the boundaries of the cardinal compass points indicate the implied intermediate directions (northeast, southeast, southwest, and northwest).

The figure below presents a compact representation of key lunar data for the summer of 2023. The horizontal axis is the day, the vertical axis is the hour of the day, and the colored areas indicate when the moon is above the horizon. The vertical gray bars (new Moons) and blue bars (full Moons) indicate key Moon phases. The label associated with each bar indicates the date and time that the phase is obtained, and the companion time labels indicate the rise and set times of the Moon for the nearest time interval in which the moon is above the horizon.

Moon Rise, Set & Phases in the Summer in San Diego

Moon Rise, Set & Phases in the Summer in San DiegoJunJulAug12 AM12 AM4 AM4 AM8 AM8 AM12 PM12 PM4 PM4 PM8 PM8 PM12 AM12 AMSpringFallMay 510:35 AMMay 510:35 AMMay 198:54 AMMay 198:54 AMJun 38:42 PMJun 38:42 PMJun 179:38 PMJun 179:38 PMJul 34:39 AMJul 34:39 AMJul 1711:32 AMJul 1711:32 AMAug 111:32 AMAug 111:32 AMAug 162:39 AMAug 162:39 AMAug 306:36 PMAug 306:36 PMSep 146:40 PMSep 146:40 PMSep 292:58 AMSep 292:58 AM6:49 PM6:49 PM5:51 AM5:51 AM8:12 PM8:12 PM7:54 PM7:54 PM5:52 AM5:52 AM8:03 PM8:03 PM7:50 PM7:50 PM5:38 AM5:38 AM8:26 PM8:26 PM7:30 PM7:30 PM5:40 AM5:40 AM8:08 PM8:08 PM7:28 PM7:28 PM6:58 AM6:58 AM6:28 PM6:28 PM6:54 AM6:54 AM
The time in which the moon is above the horizon (light blue area), with new moons (dark gray lines) and full moons (blue lines) indicated. The shaded overlays indicate night and civil twilight.

We base the humidity comfort level on the dew point, as it determines whether perspiration will evaporate from the skin, thereby cooling the body. Lower dew points feel drier and higher dew points feel more humid. Unlike temperature, which typically varies significantly between night and day, dew point tends to change more slowly, so while the temperature may drop at night, a muggy day is typically followed by a muggy night.

The chance that a given day will be muggy in San Diego is very rapidly increasing during the summer, rising from 0% to 21% over the course of the season.

The highest chance of a muggy day during the summer is 23% on August 27.

For reference, on August 27, the muggiest day of the year, there are muggy conditions 23% of the time, while on January 1, the least muggy day of the year, there are muggy conditions 0% of the time.

Humidity Comfort Levels in the Summer in San Diego

Humidity Comfort Levels in the Summer in San DiegoJunJulAug0%0%10%10%20%20%30%30%40%40%50%50%60%60%70%70%80%80%90%90%100%100%SpringFallAug 2723%Aug 2723%Jun 10%Jun 10%Jul 14%Jul 14%Aug 115%Aug 115%muggymuggyhumidhumidcomfortablecomfortabledrydry
dry 55°F comfortable 60°F humid 65°F muggy 70°F oppressive 75°F miserable
The percentage of time spent at various humidity comfort levels, categorized by dew point.

This section discusses the wide-area hourly average wind vector (speed and direction) at 10 meters above the ground. The wind experienced at any given location is highly dependent on local topography and other factors, and instantaneous wind speed and direction vary more widely than hourly averages.

The average hourly wind speed in San Diego is decreasing during the summer, decreasing from 7.1 miles per hour to 5.9 miles per hour over the course of the season.

For reference, on December 11, the windiest day of the year, the daily average wind speed is 8.0 miles per hour, while on August 23, the calmest day of the year, the daily average wind speed is 5.8 miles per hour.

The lowest daily average wind speed during the summer is 5.8 miles per hour on August 23.

Average Wind Speed in the Summer in San Diego

Average Wind Speed in the Summer in San DiegoJunJulAug0 mph0 mph2 mph2 mph4 mph4 mph6 mph6 mph8 mph8 mph10 mph10 mph12 mph12 mphSpringFallAug 235.8 mphAug 235.8 mphJun 17.1 mphJun 17.1 mphJul 16.2 mphJul 16.2 mphAug 16.0 mphAug 16.0 mph
The average of mean hourly wind speeds (dark gray line), with 25th to 75th and 10th to 90th percentile bands.

The hourly average wind direction in San Diego throughout the summer is predominantly from the west, with a peak proportion of 79% on June 2.

Wind Direction in the Summer in San Diego

Wind Direction in the Summer in San DiegoJunJulAug0%100%20%80%40%60%60%40%80%20%100%0%SpringFallwestnorthsouth
northeastsouthwest
The percentage of hours in which the mean wind direction is from each of the four cardinal wind directions, excluding hours in which the mean wind speed is less than 1.0 mph. The lightly tinted areas at the boundaries are the percentage of hours spent in the implied intermediate directions (northeast, southeast, southwest, and northwest).

San Diego is located near a large body of water (e.g., ocean, sea, or large lake). This section reports on the wide-area average surface temperature of that water.

The average surface water temperature in San Diego is increasing during the summer, rising by 6°F, from 64°F to 70°F, over the course of the season.

The highest average surface water temperature during the summer is 70°F on August 27.

Average Water Temperature in the Summer in San Diego

Average Water Temperature in the Summer in San DiegoJunJulAug58°F58°F60°F60°F62°F62°F64°F64°F66°F66°F68°F68°F70°F70°F72°F72°F74°F74°FSpringFallAug 2770°FAug 2770°FJun 164°FJun 164°FJul 166°FJul 166°FAug 169°FAug 169°F
The daily average water temperature (purple line), with 25th to 75th and 10th to 90th percentile bands.

Definitions of the growing season vary throughout the world, but for the purposes of this report, we define it as the longest continuous period of non-freezing temperatures (≥ 32°F) in the year (the calendar year in the Northern Hemisphere, or from July 1 until June 30 in the Southern Hemisphere).

Temperatures in San Diego are sufficiently warm year round that it is not entirely meaningful to discuss the growing season in these terms. We nevertheless include the chart below as an illustration of the distribution of temperatures experienced throughout the year.

Time Spent in Various Temperature Bands and the Growing Season in the Summer in San Diego

Time Spent in Various Temperature Bands and the Growing Season in the Summer in San DiegoJunJulAug0%100%10%90%20%80%30%70%40%60%50%50%60%40%70%30%80%20%90%10%100%0%SpringFall100%Jul 17100%Jul 17coolcomfortablewarm
frigid 15°F freezing 32°F very cold 45°F cold 55°F cool 65°F comfortable 75°F warm 85°F hot 95°F sweltering
The percentage of time spent in various temperature bands. The black line is the percentage chance that a given day is within the growing season.

Growing degree days are a measure of yearly heat accumulation used to predict plant and animal development, and defined as the integral of warmth above a base temperature, discarding any excess above a maximum temperature. In this report, we use a base of 50°F and a cap of 86°F.

The average accumulated growing degree days in San Diego are very rapidly increasing during the summer, increasing by 1,759°F, from 1,593°F to 3,352°F, over the course of the season.

Growing Degree Days in the Summer in San Diego

Growing Degree Days in the Summer in San DiegoJunJulAug1,500°F1,500°F2,000°F2,000°F2,500°F2,500°F3,000°F3,000°F3,500°F3,500°FSpringFallJun 11,593°FJun 11,593°FAug 313,352°FAug 313,352°FJul 12,090°FJul 12,090°FAug 12,709°FAug 12,709°F
The average growing degree days accumulated over the course of the summer, with 25th to 75th and 10th to 90th percentile bands.

This section discusses the total daily incident shortwave solar energy reaching the surface of the ground over a wide area, taking full account of seasonal variations in the length of the day, the elevation of the Sun above the horizon, and absorption by clouds and other atmospheric constituents. Shortwave radiation includes visible light and ultraviolet radiation.

The average daily incident shortwave solar energy in San Diego is decreasing during the summer, falling by 1.1 kWh, from 8.1 kWh to 7.0 kWh, over the course of the season.

The highest average daily incident shortwave solar energy during the summer is 8.4 kWh on June 21.

Average Daily Incident Shortwave Solar Energy in the Summer in San Diego

Average Daily Incident Shortwave Solar Energy in the Summer in San DiegoJunJulAug0 kWh0 kWh1 kWh1 kWh2 kWh2 kWh3 kWh3 kWh4 kWh4 kWh5 kWh5 kWh6 kWh6 kWh7 kWh7 kWh8 kWh8 kWh9 kWh9 kWhSpringFallJun 218.4 kWhJun 218.4 kWhJun 18.1 kWhJun 18.1 kWhAug 317.0 kWhAug 317.0 kWhAug 17.8 kWhAug 17.8 kWh
The average daily shortwave solar energy reaching the ground per square meter (orange line), with 25th to 75th and 10th to 90th percentile bands.

For the purposes of this report, the geographical coordinates of San Diego are 32.715 deg latitude, -117.157 deg longitude, and 62 ft elevation.

The topography within 2 miles of San Diego contains only modest variations in elevation, with a maximum elevation change of 305 feet and an average elevation above sea level of 93 feet. Within 10 miles contains only modest variations in elevation (1,552 feet). Within 50 miles contains very significant variations in elevation (6,483 feet).

The area within 2 miles of San Diego is covered by artificial surfaces (72%) and water (21%), within 10 miles by artificial surfaces (56%) and water (37%), and within 50 miles by water (48%) and shrubs (33%).

This report illustrates the typical weather in San Diego, based on a statistical analysis of historical hourly weather reports and model reconstructions from January 1, 1980 to December 31, 2016.

Temperature and Dew Point

There are 3 weather stations near enough to contribute to our estimation of the temperature and dew point in San Diego.

For each station, the records are corrected for the elevation difference between that station and San Diego according to the International Standard Atmosphere , and by the relative change present in the MERRA-2 satellite-era reanalysis between the two locations.

The estimated value at San Diego is computed as the weighted average of the individual contributions from each station, with weights proportional to the inverse of the distance between San Diego and a given station.

The stations contributing to this reconstruction are:

To get a sense of how much these sources agree with each other, you can view a comparison of San Diego and the stations that contribute to our estimates of its temperature history and climate. Please note that each source's contribution is adjusted for elevation and the relative change present in the MERRA-2 data.

Other Data

All data relating to the Sun's position (e.g., sunrise and sunset) are computed using astronomical formulas from the book, Astronomical Algorithms 2nd Edition , by Jean Meeus.

All other weather data, including cloud cover, precipitation, wind speed and direction, and solar flux, come from NASA's MERRA-2 Modern-Era Retrospective Analysis . This reanalysis combines a variety of wide-area measurements in a state-of-the-art global meteorological model to reconstruct the hourly history of weather throughout the world on a 50-kilometer grid.

Land Use data comes from the Global Land Cover SHARE database , published by the Food and Agriculture Organization of the United Nations.

Elevation data comes from the Shuttle Radar Topography Mission (SRTM) , published by NASA's Jet Propulsion Laboratory.

Names, locations, and time zones of places and some airports come from the GeoNames Geographical Database .

Time zones for airports and weather stations are provided by AskGeo.com .

Maps are © OpenStreetMap contributors.

Disclaimer

The information on this site is provided as is, without any assurances as to its accuracy or suitability for any purpose. Weather data is prone to errors, outages, and other defects. We assume no responsibility for any decisions made on the basis of the content presented on this site.

We draw particular cautious attention to our reliance on the MERRA-2 model-based reconstructions for a number of important data series. While having the tremendous advantages of temporal and spatial completeness, these reconstructions: (1) are based on computer models that may have model-based errors, (2) are coarsely sampled on a 50 km grid and are therefore unable to reconstruct the local variations of many microclimates, and (3) have particular difficulty with the weather in some coastal areas, especially small islands.

We further caution that our travel scores are only as good as the data that underpin them, that weather conditions at any given location and time are unpredictable and variable, and that the definition of the scores reflects a particular set of preferences that may not agree with those of any particular reader.

Please review our full terms contained on our Terms of Service page.