Today | Weather | Thursday, May 21, 2026

Weather in Waterbury, Connecticut

05:09 AM
Now
Cloudy Weather
57° F
Feels Like 57°
Precipitation 40 %
Wind 6 mph
Humidity 65 %
Today
Rainy Weather
Day 63°
Night 48°
Precipitation 62 %
Wind 6 mph
UV Index (0 - 11+) 4

Waterbury Weather Forecast Updated

7 minutes ago
Last updated on
Weather Forecast History
Last Year's Weather on This Day (May 21, 2025)
Rainy Weather

Day

54°

Night

45°

Wind

11 mph

UV Index

2

Precipitation

90 %

Air Quality in Waterbury

NOW
29 AQI
Good air quality Dominant pollutant: O3

Pollutant Concentrations:

PM2.5 2.01 µg/m³
PM10 3.2 µg/m³
O3 0.032 ppm
NO2 6.4 ppb
SO2 1.6 ppb
CO 0.13 ppm
NH3 1.17 µg/m³
NO 0 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)
PM2.52.01 µg/m³
PM103.2 µg/m³
O361.87 µg/m³
NO212.06 µg/m³
SO24.17 µg/m³
CO148.59 µg/m³
NH31.17 µg/m³
NO0 µg/m³