Today | Weather | Monday, May 25, 2026

Weather in Simi Valley, California

08:55 PM
Now
Night
59° F
Feels Like 57°
Precipitation 0 %
Wind 6 mph
Humidity 72 %
Today
Cloudy Night
Day 72°
Night 54°
Precipitation 6 %
Wind 6 mph

Simi Valley Weather Forecast Updated

19 minutes ago
Last updated on
Weather Forecast History
Last Year's Weather on This Day (May 25, 2025)
Cloudy Weather

Day

75°

Night

52°

Wind

7 mph

UV Index

11

Precipitation

0 %

Air Quality in Simi Valley

NOW
48 AQI
Good air quality Dominant pollutant: O3

Pollutant Concentrations:

PM2.5 2.54 µg/m³
PM10 7.47 µg/m³
O3 0.052 ppm
NO2 0.2 ppb
SO2 0.2 ppb
CO 0.10 ppm
NH3 0 µg/m³
NO 0 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)
PM2.52.54 µg/m³
PM107.47 µg/m³
O3101.59 µg/m³
NO20.42 µg/m³
SO20.6 µg/m³
CO111.02 µg/m³
NH30 µg/m³
NO0 µg/m³