Today | Weather | Monday, September 21, 2026

Weather in Watertown, South Dakota

12:55 PM
Now
Cloudy Weather
54° F
Feels Like 55°
Precipitation 49 %
Wind 7 mph
UV Index (0 - 11+) 2
Humidity 82 %
Today
Partly Sunny with Showers
Day 57°
Night 48°
Precipitation 100 %
Wind 8 mph
UV Index (0 - 11+) 2

Watertown Weather Forecast Updated

Last updated on

Air Quality in Watertown

NOW
19 AQI
Good air quality Dominant pollutant: O3

Pollutant Concentrations:

PM2.5 0.84 µg/m³
PM10 0.89 µg/m³
O3 0.021 ppm
NO2 1.1 ppb
SO2 0 ppb
CO 0.14 ppm
NH3 0.6 µg/m³
NO 0.24 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)
PM2.50.84 µg/m³
PM100.89 µg/m³
O341.27 µg/m³
NO22.05 µg/m³
SO20.04 µg/m³
CO165.47 µg/m³
NH30.6 µg/m³
NO0.24 µg/m³