Today | Weather | Wednesday, May 20, 2026

Weather in Gresham, Oregon

01:54 PM
Now
Cloudy Weather
63° F
Feels Like 73°
Precipitation 0 %
Wind 6 mph
UV Index (0 - 11+) 8
Humidity 54 %
Today
Cloudy Weather
Day 70°
Night 48°
Precipitation 1 %
Wind 6 mph
UV Index (0 - 11+) 9

Warning: High UV Index Today: 9

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.

Gresham Weather Forecast Updated

Last updated on
Weather Forecast History
Last Year's Weather on This Day (May 20, 2025)
Partly Sunny with Showers

Day

61°

Night

46°

Wind

6 mph

UV Index

4

Precipitation

87 %

Air Quality in Gresham

NOW
42 AQI
Good air quality Dominant pollutant: O3

Pollutant Concentrations:

PM2.5 1.52 µg/m³
PM10 3.14 µg/m³
O3 0.045 ppm
NO2 0.2 ppb
SO2 0.1 ppb
CO 0.10 ppm
NH3 0.3 µg/m³
NO 0.12 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)
PM2.51.52 µg/m³
PM103.14 µg/m³
O388.2 µg/m³
NO20.46 µg/m³
SO20.38 µg/m³
CO118.4 µg/m³
NH30.3 µg/m³
NO0.12 µg/m³