Climate change in San Diego, California
Climate change is affecting locations like San Diego in a variety of ways. In fall, these impacts include more unusually warm days, more frequent fire weather, and increased food prices.
Explore these pages to learn how people in San Diego are at risk in a warming world.
Since 1970, average annual temperatures in San Diego have gotten 0.2°F warmer.
Warming puts people and ecosystems at risk from more frequent and intense extreme weather.
Overall, the contiguous U.S. is about 2.8°F warmer today than in 1970, based on average temperatures.
Data source: NOAA ACIS
Since 1970, San Diego's annual precipitation has decreased by 1.8 inches.
Climate change is supercharging the water cycle and bringing heavier precipitation extremes across the U.S.
For every 1°F of warming, the air can hold 4% more moisture, increasing the chances of heavier downpours that contribute to flash flooding hazards.
Data source: NOAA ACIS
As of September 30, 2026, San Diego has experienced 131 days this year with temperatures made twice as likely by climate change.
This is according to the Climate Shift Index (CSI), which quantifies the influence of human-caused climate change on daily average temperatures. Temperatures on these days had a CSI level 2 or higher, which indicates local temperatures were at least two times more likely due to climate change.
The CSI ranges from -5 to +5. Positive levels indicate temperatures made more likely due to climate change (while negative scores indicate conditions made less likely).
Data source: Climate Shift Index
San Diego's climate threats in include:
About 72% of California is currently in drought or abnormally dry.
Rising temperatures are worsening the risk of drought in parts of the U.S.
Droughts can lead to crop failure or pasture losses, impact water supplies, affect public health, degrade ecosystems, and increase the amount of fuel for wildfires by drying grasses and forests.
The map shows the percentage of land area that is abnormally dry (category D0) or in drought (categories D1-4). This is according to the U.S. Drought Monitor's drought classification scale.
Data source: U.S. Drought Monitor
The sea level in San Diego is projected to rise 0.7 feet by 2050 even if nations meet their pledged commitments to reduce heat-trapping pollution.
Increasing flood risk is driven by our warming climate, which is causing sea levels around the world to rise. Rising sea levels push tides and storm surges higher and farther inland.
Climate Central’s Coastal Risk Finder provides maps and analysis of the people, homes, and land in the U.S. projected to be at risk from worsening coastal flooding driven by rising seas.
Explore some ways climate change is affecting San Diego in fall
More warm fall days
Fall (September-November) has warmed nationwide since 1970.

Key concepts:
- Fall (September - November) has warmed nationwide since 1970.
- Warming is nationwide, strongest in the Southwest.
- Hotter falls extend risks from heat, wildfire, allergies, and more.
More fire weather
Wildfire seasons are lengthening and intensifying.

Key concepts:
- Climate Central analyzed U.S. fire weather (hot, dry, windy conditions) from 1973–2024.
- Wildfire seasons are lengthening and intensifying, especially in the West.
- Fire weather is rising most in spring nationwide
Impacts to food prices
Extreme events fueled by climate change can damage crops, reduce yields, and disrupt supply chains.

Key concepts:
- Food and climate change are closely linked. Food systems account for about one-quarter of all heat-trapping pollution.
- Meanwhile, extreme events fueled by climate change can damage crops, reduce yields, and disrupt supply chains — all of which can drive food prices higher.
- The availability, quality, and affordability of food reflect a complex set of climatic and socioeconomic factors. Emerging research is providing insight into the role of climate change.
More graphics about San Diego and climate change
Browse climate-related graphics for all seasons localized for San Diego, available for download and use consistent with our Terms of use.