Today | Weather | Wednesday, October 21, 2026

Weather in Portland, Oregon

03:02 PM
Now
Sunny Weather
72° F
Feels Like 73°
Precipitation 0 %
Wind 6 mph
UV Index (0 - 11+) 2
Humidity 37 %
Today
Sunny Weather
Day 75°
Night 46°
Precipitation 0 %
Wind 4 mph
UV Index (0 - 11+) 3

Portland Weather Forecast Updated

47 minutes ago
Last updated on
Weather Forecast History
Last Year's Weather on This Day (October 21, 2025)
Night

Day

61°

Night

43°

Wind

5 mph

Precipitation

1 %

Air Quality in Portland

NOW
40 AQI
Good air quality Dominant pollutant: O3

Pollutant Concentrations:

PM2.5 9.38 µg/m³
PM10 12.35 µg/m³
O3 0.043 ppm
NO2 1.4 ppb
SO2 0.6 ppb
CO 0.17 ppm
NH3 0.86 µg/m³
NO 0.54 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)
PM2.5 – 9.38 µg/m³
PM10 – 12.35 µg/m³
O3 – 84.31 µg/m³
NO2 – 2.72 µg/m³
SO2 – 1.5 µg/m³
CO – 189.11 µg/m³
NH3 – 0.86 µg/m³
NO – 0.54 µg/m³