Air Quality Index in San Diego, CA
San Diego is known for its beautiful beaches and mild climate. While the air quality is generally good, it can sometimes be affected by factors like traffic, wildfires, and pollution from nearby industries.
Air Quality Index
February 16, 2025Air quality is ideal, with minimal or no risk to health.
Air Quality Index
February 17, 2025Everyone may begin to experience health effects, and sensitive groups may face more serious issues.
Air Quality Index
February 18, 2025Members of sensitive groups, such as children, the elderly, and individuals with respiratory conditions, may experience adverse health effects. The general population is less likely to be affected.
Air Quality Index
February 19, 2025Air quality is acceptable, but some individuals, particularly those unusually sensitive to air pollution, may experience minor health effects.
Air Quality Index
February 20, 2025A health alert indicating that everyone may experience serious effects from air pollution.
Air Quality Index
February 21, 2025Members of sensitive groups, such as children, the elderly, and individuals with respiratory conditions, may experience adverse health effects. The general population is less likely to be affected.
5-Day Air Quality Index Forecast in San Diego, CA
Nitrogen dioxide is a reddish-brown gas formed primarily from the combustion of fossil fuels, especially from vehicles, power plants, and industrial processes.
Ozone is a gas composed of three oxygen atoms, formed in the atmosphere through chemical reactions between volatile organic compounds (VOCs) and nitrogen oxides (NOₓ) in the presence of sunlight.
PM2.5 refers to airborne particles with a diameter of 2.5 micrometers or smaller, consisting of various components like dust, soot, and liquid droplets, often originating from combustion and chemical reactions in the atmosphere.
M10 refers to particulate matter with a diameter of 10 micrometers or smaller, typically including dust, pollen, and mold spores, originating from construction, road dust, and natural sources.
Tips to Protect Yourself from Unhealthy Air Quality in San Diego, CA

When the air quality is poor, spend as much time indoors as possible. Keep windows and doors closed, and use air purifiers to help clean the air inside your home.

Avoid outdoor exercise or any strenuous activities during high pollution days. If you need to go outside, try to do it during times when pollution levels are lower, like early morning or late evening.

Check the air quality index regularly and consider wearing a mask designed for air pollution (like an N95 mask) to protect your lungs when the AQI is high.
FAQ
Frequently Asked Questions-
When is AQI usually the worst in San Diego?
The AQI in San Diego is usually the worst during the summer and fall, especially when wildfires occur. Wildfires in nearby areas can cause a lot of smoke, which lowers air quality. High traffic and increased temperatures can also worsen the AQI during these months.
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What are common pollutants that impact AQI in San Diego?
Common pollutants that affect the AQI in San Diego include particulate matter (PM2.5), ozone, and nitrogen dioxide (NO2). PM2.5 comes from car exhaust, wildfires, and other sources. Ozone forms when sunlight reacts with vehicle emissions and industrial pollution. NO2 is released by cars and industrial facilities and contributes to air pollution.
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Are there specific areas in San Diego with better AQI?
Areas farther from traffic and industrial zones tend to have better air quality in San Diego. Coastal areas and higher elevation spots, such as parts of the city near the mountains, often have cleaner air. In contrast, areas near major freeways, urban centers, or industrial zones may experience worse air quality due to pollution from vehicles and businesses.
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