Today | Weather | Wednesday, May 20, 2026

Weather in Portland, Oregon

01:53 PM
Now
Cloudy Weather
64° F
Feels Like 73°
Precipitation 0 %
Wind 7 mph
UV Index (0 - 11+) 8
Humidity 53 %
Today
Cloudy Weather
Day 72°
Night 48°
Precipitation 1 %
Wind 7 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.

Portland Weather Forecast Updated

50 minutes ago
Last updated on
Weather Forecast History
Last Year's Weather on This Day (May 20, 2025)
Rainy Weather

Day

63°

Night

46°

Wind

6 mph

UV Index

3

Precipitation

81 %

Air Quality in Portland

NOW
40 AQI
Good air quality Dominant pollutant: O3

Pollutant Concentrations:

PM2.5 1.31 µg/m³
PM10 3.03 µg/m³
O3 0.043 ppm
NO2 0.2 ppb
SO2 0.1 ppb
CO 0.10 ppm
NH3 0.24 µg/m³
NO 0.1 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)
PM2.51.31 µg/m³
PM103.03 µg/m³
O384.7 µg/m³
NO20.4 µg/m³
SO20.32 µg/m³
CO116.49 µg/m³
NH30.24 µg/m³
NO0.1 µg/m³