Today | Weather | Tuesday, July 21, 2026

Weather in Hayward, California

02:09 AM
Now
Cloudy Weather
64° F
Feels Like 63°
Precipitation 0 %
Wind 6 mph
Humidity 75 %
Today
Cloudy Weather
Day 91°
Night 66°
Precipitation 3 %
Wind 9 mph
UV Index (0 - 11+) 10

Warning: High UV Index Today: 10

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.

Hayward Weather Forecast Updated

44 minutes ago
Last updated on
Weather Forecast History
Last Year's Weather on This Day (July 21, 2025)
Cloudy Night

Day

68°

Night

57°

Wind

10 mph

Precipitation

25 %

Air Quality in Hayward

NOW
28 AQI
Good air quality Dominant pollutant: O3

Pollutant Concentrations:

PM2.5 5.75 µg/m³
PM10 14.15 µg/m³
O3 0.030 ppm
NO2 1 ppb
SO2 0.4 ppb
CO 0.08 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)
PM2.55.75 µg/m³
PM1014.15 µg/m³
O359.63 µg/m³
NO21.94 µg/m³
SO20.98 µg/m³
CO95.96 µg/m³
NH30 µg/m³
NO0 µg/m³