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Contents
- The climate of San Diego
- The best time to visit San Diego
- The worst time to visit San Diego
- Spring weather in San Diego
- Summer weather in San Diego
- Autumn weather in San Diego
- Winter weather in San Diego
- Weather in January
- Weather in February
- Weather in March
- Weather in April
- Weather in May
- Weather in June
- Weather in July
- Weather in August
- Weather in September
- Weather in October
- Weather in November
- Weather in December
- Frequently asked questions
- Average temperature
- Average pressure
- Average wind speed
- Average humidity
- Average rainfall
- Average rainfall days
- Average sea temperature
- Average daylight
- Average sunshine
- Average sunshine days
- Average UV index
- Average cloud cover
- Average visibility
Coronado Island in San Diego, California, USA,
Climate and monthly weather forecast
The climate of San Diego
Situated in southern California, San Diego boasts the highly predictable BSk classification of climate, known as mid-latitude steppe climate according to the Köppen climate classification system. Throughout the year, San Diego enjoys a mild climate with variations in temperature, humidity levels, rainfall, and other weather parameters lending a unique characteristic to each changing season.
Specifically, high temperatures throughout the year range from 63.1°F (17.3°C) to 77.4°F (25.2°C) with the warmest month being August. The lowest temperatures, varying from 51.8°F (11°C) to 65.7°F (18.7°C), occur in December and August. The relative humidity throughout the year fluctuates from 59% to 73%, contributing to the overall comfort or discomfort level experienced by inhabitants and visitors alike in San Diego.
Rainfall in San Diego exhibits a pattern of fluctuation throughout the year, adding up to 0.12" (3mm) in the driest month of June and reaching up to 1.65" (42mm) in the month with the heaviest precipitation, December. The number of rainfall days in a month varies equally, hitting a low of 2.7 days in June while peaking at 7.6 days in March.
In San Diego, daylight hours range from 10 hours in December to 14.3 hours in June, the longest daylight month. Correspondingly, the amount of sunshine in hours varies from 6.7 hours in December to 11.9 hours in July, with June, July, and August all boasting ample sunshine hours.
Specifically, high temperatures throughout the year range from 63.1°F (17.3°C) to 77.4°F (25.2°C) with the warmest month being August. The lowest temperatures, varying from 51.8°F (11°C) to 65.7°F (18.7°C), occur in December and August. The relative humidity throughout the year fluctuates from 59% to 73%, contributing to the overall comfort or discomfort level experienced by inhabitants and visitors alike in San Diego.
Rainfall in San Diego exhibits a pattern of fluctuation throughout the year, adding up to 0.12" (3mm) in the driest month of June and reaching up to 1.65" (42mm) in the month with the heaviest precipitation, December. The number of rainfall days in a month varies equally, hitting a low of 2.7 days in June while peaking at 7.6 days in March.
In San Diego, daylight hours range from 10 hours in December to 14.3 hours in June, the longest daylight month. Correspondingly, the amount of sunshine in hours varies from 6.7 hours in December to 11.9 hours in July, with June, July, and August all boasting ample sunshine hours.
The best time to visit San Diego
The ideal time to visit San Diego depends largely on individual preferences, particularly when it comes to the desired weather and temperature. For those who prefer a cooler climate; however, the best time for a visit would arguably be in the months from November to March. During these months, temperatures average between 63.3°F (17.4°C) and 68.5°F (20.3°C), while relative humidity levels remain steady, averaging between 59% and 64%.
For those desiring a warmer climate aligned with long daylight hours, the months of June, July, and August are the best. During these months, San Diego experiences temperatures as high as 70.7°F (21.5°C) to 77.4°F (25.2°C) and enjoys the longest daylight hours of 14.1 hours to 14.3 hours.
For those desiring a warmer climate aligned with long daylight hours, the months of June, July, and August are the best. During these months, San Diego experiences temperatures as high as 70.7°F (21.5°C) to 77.4°F (25.2°C) and enjoys the longest daylight hours of 14.1 hours to 14.3 hours.
The worst time to visit San Diego
Just as the best times to visit San Diego are subjective and hinged upon personal preference, the same is true for identifying the worst time to visit the city. Nevertheless, for those not keen on higher levels of humidity, the months between May and September might be best avoided as humidity levels reach their peak during this period, going as high as 72%-73%.
Spring weather in San Diego
Spring, spanning March, April, and May, welcomes tourists with mild weather. Temperatures fluctuate between 52.7°F (11.5°C) to 67.6°F (19.8°C), while rainfall levels drop significantly from 0.83" (21mm) in March to 0.39" (10mm) in May. This period also signals an increase in daylight hours, with an average range from 12 hours to 13.9 hours.
Summer weather in San Diego
San Diego's summer season, encompassing June, July, and August, is characterized by warm temperatures ranging from 58.8°F (14.9°C) to 77.4°F (25.2°C), and minimal rainfall, with the lowest rate of 0.12" (3mm) in June. Tourists who love longer daylight hours will relish summers in San Diego where daylight can last from 14.1 hours to 14.3 hours in a single day.
Autumn weather in San Diego
In the autumn months of September, October, and November, temperatures begin to drop from 65.1°F (18.4°C) to 63.3°F (17.4°C) and rainfall begins to increase, reaching 0.87" (22mm) in November. Material changes in daylight hours start to become noticeable, moving from 12.4 hours in September to 10.5 hours in November.
Winter weather in San Diego
Winter in San Diego, stretching across December, January, and February, is mild with average high temperatures ranging from 63.1°F (17.3°C) to 64.4°F (18°C) and average low temperatures hovering between 51.8°F (11°C) and 52.7°F (11.5°C). December features the highest levels of rainfall at 1.65" (42mm), and sees daylight hours at their shortest, averaging at 10 hours. This period is marked by relatively low humidity levels, averaging between 59%-64%.
Weather in January
January in San Diego rings in the New Year with slightly cooler temperatures and increased precipitation. This month sees a slight dip in average high temperature from 64.2°F (17.9°C) to 63.1°F (17.3°C). With an average rainfall of 1.06" (27mm), it is not the wettest month, but it is close. Weather in January »
Weather in February
February brings subtle changes to San Diego's weather pattern. This month experiences a slight ascend in relative humidity to 64%, with an expectation of more occasional rain showers. The slight increase in rainfall to 1.5" (38mm) might be an indication of a wetter period. Weather in February »
Weather in March
In March, the weather in this Californian city starts to lean towards spring. With a small decrease in rainfall to 0.83" (21mm), there is a noticeable shift in the climate. While it does get a little windier, with average wind speeds increasing to 6mph (9.7km/h), clear and sunny days dominate the scenery. Weather in March »
Weather in April
April welcomes much-welcomed improvements to San Diego's conditions. The precipitation drops even further down to 0.67" (17mm), as rainfall becomes less frequent. The month also sees a significant increase in sunshine hours, elevating to 10.9 hours, and adding warmth and brightness to the scenario. Weather in April »
Weather in May
San Diego embarks upon its summer season in May. There is a noticeable decline in rainfall, dropping to 0.39" (10mm), indicating the beginning of a drier season. With the increase in temperature, there is a considerable augmentation in humidity to 72%, adding a hint of heaviness to the air. Weather in May »
Weather in June
June in San Diego sees a further rise in temperature and abundance of sunshine. With a dip in rainfall to a minimal 0.12" (3mm), it is one of the driest months. Prolonged sunlight and low cloud coverage allow for more outdoor activities, with beachgoers relishing in the highest sea temperatures. Weather in June »
Weather in July
July is a standout month for San Diego, boasting the hottest temperatures of the year, peaking at an average high of 75.4°F (24.1°C). It is the epitome of summer weather with hot days and warm, comfortable nights. This month embraces quality beach weather, and it offers some of the year's best conditions for water sports. Weather in July »
Weather in August
In August, the summery ambiance continues in San Diego. With the highest average high temperature of 77.4°F (25.2°C), the city revels in peak summer. The month starts with an upswing in sea temperatures while the extended daylight hours encourage outdoor activities. Weather in August »
Weather in September
September in San Diego offers the residents and visitors a bit of everything. The air begins to cool from peak summer temperatures, averaging a high of 76.6°F (24.8°C). With humidity dropping to 68%, the heaviness in the air lightens, and the skies remain clear most of the time. Weather in September »
Weather in October
October in San Diego is characterized by cooling temperatures, shorter daylight hours, and a slight increase in rainfall, measuring at 0.31" (8mm). The sea temperature deals with a significant dip, dissuading people from entering the waters. Weather in October »
Weather in November
November continues to embrace San Diego's cool climate, but with an added touch of moisture. With rainfall levels rising up to 0.87" (22mm), there is an evident shift manifesting towards further precipitation. Autumn foliage colors the city, and residents enjoy the changing scenery. Weather in November »
Weather in December
December ushers in the winter season in San Diego, though winters here are relatively mild compared to most other parts of the United States. There is a noticeable increase in conditioned precipitation, with rainfall levels peeking at 1.65" (42mm). Weather in December »
Updated: Feb 9, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
How much does it rain in San Diego?
Throughout the year, there are 61.8 rainfall days, and 8.7" (221mm) of precipitation is accumulated.
What is the month with the lowest UV index in San Diego?
The months with the lowest UV index in San Diego are January through March, November and December, with an average maximum UV index of 4.
What are the coldest months in San Diego?
February is the month that records the lowest temperatures in San Diego, California, with averages ranging from a high of 63.1°F (17.3°C) to a low of 51.8°F (11°C).
What is the month with the coldest ocean in San Diego?
The month with the coldest seawater is February, with an average ocean temperature of 58.6°F (14.8°C).
When is Daylight Saving Time (DST) in San Diego?
On Sunday, March 10. 2024, at 2:00 am, Daylight Saving Time starts, and the time zone changes from PST to PDT. Daylight Saving Time ends Sunday, November 3. 2024, at 2:00 am, and the time zone reverts from PDT to PST.
What is the most humid month in San Diego?
With an average relative humidity of 73%, June is the most humid month in San Diego, California.
What is the driest month in San Diego?
The month with the least rainfall in San Diego, California, is June, when the rain falls for 2.7 days and typically collects 0.12" (3mm) of precipitation.
When are the longest days in San Diego?
June has the longest days of the year in San Diego, with an average of 14h and 18min of daylight.
What are the months with the most sunshine in San Diego?
The months with the most sunshine are July and August, with an average of 11.9h of sunshine.
What are the months with the highest UV index in San Diego?
The months with the highest UV index in San Diego, California, are July through September, with an average maximum UV index of 6.
What time of the year is the hottest in San Diego?
San Diego's August weather reaches an average high of 77.4°F (25.2°C) and an average low of 65.7°F (18.7°C), making it the warmest month.
What month is the ocean warmest in San Diego?
August is the month with the warmest seawater in San Diego, with an average ocean temperature of 68°F (20°C).
What is the least humid month in San Diego?
The least humid month in San Diego is November, with an average relative humidity of 59%.
What is the wettest month in San Diego?
December is the month with the most rainfall in San Diego. Rain falls for 5.8 days and accumulates 1.65" (42mm) of precipitation.
What is the month with the shortest days in San Diego?
December has the shortest days of the year in San Diego, with an average of 10h and 0min of daylight.
What is the month with the least sunshine in San Diego?
With an average of 6.7h of sunshine, December has the least sunshine of the year.
Average temperature
San Diego, CA
The warmest month (with the highest average high temperature) is August (77.4°F).
The month with the lowest average high temperature is February (63.1°F).
The month with the highest average low temperature is August (65.7°F).
The coldest month (with the lowest average low temperature) is February (51.8°F).
Average pressure
San Diego, CA
- Average pressure in January:
30.09"Hg - Average pressure in February:
30.04"Hg - Average pressure in March:
30.02"Hg - Average pressure in April:
29.96"Hg - Average pressure in May:
29.92"Hg - Average pressure in June:
29.88"Hg
- Average pressure in July:
29.91"Hg - Average pressure in August:
29.89"Hg - Average pressure in September:
29.88"Hg - Average pressure in October:
29.93"Hg - Average pressure in November:
30.01"Hg - Average pressure in December:
30.06"Hg
The month with the highest atmospheric pressure is January (30.09"Hg).
The months with the lowest atmospheric pressure are June and September (29.88"Hg).
Average wind speed
San Diego, CA
- Average wind speed in January:
5.3mph - Average wind speed in February:
6mph - Average wind speed in March:
6mph - Average wind speed in April:
6.3mph - Average wind speed in May:
6.3mph - Average wind speed in June:
5.7mph
- Average wind speed in July:
5.6mph - Average wind speed in August:
5.6mph - Average wind speed in September:
5.4mph - Average wind speed in October:
5.2mph - Average wind speed in November:
5.3mph - Average wind speed in December:
5.5mph
The windiest months (with the highest average wind speed) are April and May (6.3mph).
The calmest month (with the lowest average wind speed) is October (5.2mph).
Average humidity
San Diego, CA
The month with the highest relative humidity is June (73%).
The month with the lowest relative humidity is November (59%).
Average rainfall
San Diego, CA
- Average rainfall in January:
1.06" - Average rainfall in February:
1.5" - Average rainfall in March:
0.83" - Average rainfall in April:
0.67" - Average rainfall in May:
0.39" - Average rainfall in June:
0.12"
- Average rainfall in July:
0.51" - Average rainfall in August:
0.39" - Average rainfall in September:
0.39" - Average rainfall in October:
0.31" - Average rainfall in November:
0.87" - Average rainfall in December:
1.65"
The wettest month (with the highest rainfall) is December (1.65").
The driest month (with the least rainfall) is June (0.12").
Average rainfall days
San Diego, CA
- Average rainfall days in January:
5.3 days - Average rainfall days in February:
6.3 days - Average rainfall days in March:
7.6 days - Average rainfall days in April:
6.2 days - Average rainfall days in May:
5.7 days - Average rainfall days in June:
2.7 days
- Average rainfall days in July:
5.4 days - Average rainfall days in August:
3.8 days - Average rainfall days in September:
4.5 days - Average rainfall days in October:
3.4 days - Average rainfall days in November:
5.1 days - Average rainfall days in December:
5.8 days
The month with the highest number of rainy days is March (7.6 days).
The month with the least rainy days is June (2.7 days).
Average sea temperature
San Diego, CA
The best month for swimming (with the highest average sea temperature) is August (67.9°F).
The coldest month (with the lowest average sea temperature) is February (58.7°F).
Average daylight / Average sunshine
San Diego, CA
- Average daylight in January:
10h and 2min - Average daylight in February:
11h and 0min - Average daylight in March:
12h and 0min - Average daylight in April:
13h and 0min - Average daylight in May:
13h and 5min - Average daylight in June:
14h and 2min
- Average daylight in July:
14h and 1min - Average daylight in August:
13h and 2min - Average daylight in September:
12h and 2min - Average daylight in October:
11h and 2min - Average daylight in November:
10h and 3min - Average daylight in December:
10h and 0min
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 January:
6h and 5min - Average sunshine in February:
6h and 5min - Average sunshine in March:
8h and 4min - Average sunshine in April:
10h and 5min - Average sunshine in May:
10h and 5min - Average sunshine in June:
11h and 5min
- Average sunshine in July:
11h and 5min - Average sunshine in August:
11h and 5min - Average sunshine in September:
10h and 2min - Average sunshine in October:
8h and 5min - Average sunshine in November:
7h and 1min - Average sunshine in December:
6h and 4min
The months with the most sunshine are July and August (Average sunshine: 11h and 54min).
The month with the least sunshine is December (Average sunshine: 6h and 42min).
Average sunshine days
San Diego, CA
- Average sunshine days in January:
24.3 days - Average sunshine days in February:
20.6 days - Average sunshine days in March:
22.4 days - Average sunshine days in April:
21.8 days - Average sunshine days in May:
21.1 days - Average sunshine days in June:
20.5 days
- Average sunshine days in July:
20.3 days - Average sunshine days in August:
21.8 days - Average sunshine days in September:
21.8 days - Average sunshine days in October:
23.8 days - Average sunshine days in November:
23.6 days - Average sunshine days in December:
23.2 days
The month with the most sunshine days is January (24.3 days).
The month with the least sunshine days is July (20.3 days).
Average UV index
San Diego, CA
The months with the highest UV index are 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
San Diego, CA
The month with the most cloud cover is December (Cloud cover 24).
The month with the least cloud cover is August (Cloud cover 9).
Average visibility
San Diego, CA
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).