Today | Weather | Saturday, September 5, 2026

Weather in El Cajon, California

04:55 PM
Now
Cloudy Weather
91° F
Feels Like 91°
Precipitation 43 %
Wind 9 mph
UV Index (0 - 11+) 2
Humidity 25 %
Today
Cloudy Weather
Day 99°
Night 72°
Precipitation 55 %
Wind 5 mph
UV Index (0 - 11+) 8

Warning: High UV Index Today: 8

High risk of harm from unprotected sun exposure. Take precautions: wear a hat, sunglasses, and apply sunscreen regularly if you’ll be outdoors for extended periods.

El Cajon Weather Forecast Updated

7 minutes ago
Last updated on
Weather Forecast History
Last Year's Weather on This Day (September 5, 2025)
Cloudy Night

Day

84°

Night

63°

Wind

5 mph

Precipitation

0 %

Air Quality in El Cajon

NOW
44 AQI
Good air quality Dominant pollutant: O3

Pollutant Concentrations:

PM2.5 5.88 µg/m³
PM10 12.69 µg/m³
O3 0.047 ppm
NO2 0.2 ppb
SO2 0.3 ppb
CO 0.11 ppm
NH3 0 µg/m³
NO 0.04 µg/m³
PM2.5 – Fine particles <2.5μm
PM10 – Inhalable particles <10μm
O3 – Ozone
NO2 – Nitrogen dioxide
SO2 – Sulfur dioxide
CO – Carbon monoxide
NH3 – Ammonia
NO – Nitric oxide

Health Recommendations:

Air quality is considered satisfactory, and air pollution poses little or no risk.

Show raw pollutant concentrations (µg/m³)
PM2.55.88 µg/m³
PM1012.69 µg/m³
O392.59 µg/m³
NO20.46 µg/m³
SO20.79 µg/m³
CO123.25 µg/m³
NH30 µg/m³
NO0.04 µg/m³