Today | Weather | Wednesday, May 27, 2026

Weather in San Jose, California

10:29 AM
Now
Cloudy Weather
57° F
Feels Like 55°
Precipitation 0 %
Wind 21 mph
UV Index (0 - 11+) 5
Humidity 67 %
Today
Partly Sunny with Showers
Day 72°
Night 55°
Precipitation 55 %
Wind 17 mph
UV Index (0 - 11+) 11

Warning: Extreme UV Index Today: 11

Overexposure to the sun's harmful UV rays can cause sunburn and increase the risk of developing skin cancer, including melanoma. Protect yourself by wearing clothing that covers your skin, sunglasses, and a hat. Apply a broad-spectrum sunscreen with an SPF of 30 or higher every two hours, even on cloudy days. Minimize direct sun exposure during peak hours (10 AM to 4 PM) to reduce the risk.

San Jose Weather Forecast Updated

5 minutes ago
Last updated on
Weather Forecast History
Last Year's Weather on This Day (May 27, 2025)
Cloudy Weather

Day

75°

Night

54°

Wind

9 mph

UV Index

11

Precipitation

0 %

Air Quality in San Jose

NOW
36 AQI
Good air quality Dominant pollutant: O3

Pollutant Concentrations:

PM2.5 3.15 µg/m³
PM10 10.13 µg/m³
O3 0.039 ppm
NO2 0.4 ppb
SO2 0.2 ppb
CO 0.10 ppm
NH3 0 µg/m³
NO 0.09 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)
PM2.53.15 µg/m³
PM1010.13 µg/m³
O377.35 µg/m³
NO20.7 µg/m³
SO20.6 µg/m³
CO118.03 µg/m³
NH30 µg/m³
NO0.09 µg/m³