Today | Weather | Wednesday, May 20, 2026

Weather in Rapid City, South Dakota

03:52 PM
Now
Rainy Weather
68° F
Feels Like 63°
Precipitation 82 %
Wind 16 mph
UV Index (0 - 11+) 1
Humidity 36 %
Today
Partly Sunny with Showers
Day 68°
Night 43°
Precipitation 90 %
Wind 14 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.

Rapid City Weather Forecast Updated

Last updated on

Air Quality in Rapid City

NOW
57 AQI
Moderate air quality Dominant pollutant: O3

Pollutant Concentrations:

PM2.5 1.21 µg/m³
PM10 1.53 µg/m³
O3 0.056 ppm
NO2 0.1 ppb
SO2 0.2 ppb
CO 0.09 ppm
NH3 1.46 µg/m³
NO 0.05 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 acceptable; however, for some pollutants, there may be a moderate health concern for a very small number of people who are unusually sensitive to air pollution.

Show raw pollutant concentrations (µg/m³)
PM2.51.21 µg/m³
PM101.53 µg/m³
O3110.68 µg/m³
NO20.25 µg/m³
SO20.63 µg/m³
CO104.84 µg/m³
NH31.46 µg/m³
NO0.05 µg/m³