Today | Weather | Saturday, July 18, 2026

Active Weather Warnings

Air Quality Alert

Weather in Denver, Colorado

08:34 AM

Now

79° F

Feels Like 81°

Precipitation 0 %

Wind 7 mph

UV Index (0 - 11+) 4

Humidity 40 %

Today

Day 95°

Night 68°

Precipitation 2 %

Wind 10 mph

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.

Denver Weather Forecast Updated

38 minutes ago

Last updated on July 18, 2026 at 7:56 AM

Weather Forecast History

Last Year's Weather on This Day (July 18, 2025)

Day

93°

Night

64°

Wind

6 mph

UV Index

Precipitation

40 %

Air Quality in Denver

NOW

32 AQI

Good air quality Dominant pollutant: O₃

Pollutant Concentrations:

PM_2.5 3.81 µg/m³

PM₁₀ 4.16 µg/m³

O₃ 0.034 ppm

NO₂ 1.3 ppb

SO₂ 0 ppb

CO 0.09 ppm

NH₃ 5.88 µg/m³

NO 0.69 µg/m³

PM_2.5 – 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)

PM_2.5 – 3.81 µg/m³

PM₁₀ – 4.16 µg/m³

O₃ – 67.08 µg/m³

NO₂ – 2.46 µg/m³

SO₂ – 0.12 µg/m³

CO – 102.36 µg/m³

NH₃ – 5.88 µg/m³

NO – 0.69 µg/m³

View Hourly Air Quality Forecast

Weather Alerts and Warnings for Denver

Air Quality Alert

Air Quality Alert issued July 17 at 4:10PM MDT by NWS Denver CO

Jul 17, 4:10 PM → Jul 18, 4:00 PM

The Colorado Department of Public Health and Environment has
issued the following...

WHAT...Ozone Action Day Alert.

WHERE...Douglas, Jefferson, Denver, western Arapahoe, western
Adams, Broomfield, Boulder, Larimer, and Weld Counties

WHEN...400 PM Friday July 17 to 400 PM Saturday July 18

IMPACTS...Ozone Action Day Alert is now in effect for the Front
Range Urban Corridor. Hot and sunny weather will result in
concentrations of ozone reaching the Unhealthy for Sensitive
Groups category on Friday and Saturday. The highest concentrations
are most likely in the western portions of the Denver Metro area,
including the lower foothills. For Colorado air quality
conditions, forecasts, and advisories, visit:
https://www.colorado.gov/airquality/colorado_summary.aspx If
possible, please help us reduce ozone pollution by limiting
driving gas and diesel-powered vehicles until at least 4 p.m.
Saturday, July 18, 2026. Colorado is also addressing ozone
pollution through state policies. For more information about
health impacts and how ozone pollution forms in Colorado, visit:
https://cdphe.colorado.gov/ozone- pollution-and-your-health

HEALTH INFORMATION...Increasing likelihood of respiratory symptoms
and breathing discomfort in active children and adults and people
with lung disease, such as asthma. Active children and adults, and
people with lung disease, such as asthma, should reduce prolonged
or heavy outdoor exertion.

Updated: Jul 18, 7:56 AM Source: NWS Alert