Today | Weather | Wednesday, September 24, 2025

Weather in Thornton, Colorado

03:44 PM
Now
Cloudy Weather
68° F
Feels Like 72°
Precipitation 0 %
Wind 6 mph
UV Index (0 - 11+) 11
Humidity 38 %
Today
Cloudy Weather
Day 68°
Night 45°
Precipitation 0 %
Wind 8
UV Index (0 - 11+) 11

Warning: Extreme UV Index Today: 11+

Overexposure to the sun's harmful UV rays can cause sunburn and increase the risk of developing skin cancer, including melanoma. Protect yourself by wearing clothing that covers your skin, sunglasses, and a hat. Apply a broad-spectrum sunscreen with an SPF of 30 or higher every two hours, even on cloudy days. Minimize direct sun exposure during peak hours (10 AM to 4 PM) to reduce the risk.

Thornton Weather Forecast Updated

16 minutes ago
Last updated on

Weather Forecast History

Last Year's Weather on This Day (September 24, 2024)

Sunny Weather

Day

75°

Night

52°

Wind

4 mph

UV Index

5

Precipitation

0

Air quality in Thornton

NOW
42 AQI
Good air quality Dominant pollutant: PM2.5

Pollutant Concentrations:

PM2.5 8.33 µg/m³
PM10 19.77 µg/m³
O₃ 41.25 ppb
NO₂ 11.49 ppb
SO₂ 1.25 ppb
CO 218.59 ppb
PM2.5 – Fine particles <2.5μm
PM10 – Inhalable particles <10μm
O3 – Ozone
NO2 – Nitrogen dioxide
SO2 – Sulfur dioxide
CO – Carbon monoxide

Health Recommendations:

With this level of air quality, you have no limitations. Enjoy the outdoors