Weld County, CO

Alerts

Advisory Area
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Alerts are listed in order of start time and level of severity. Click on the alert title to read details for each alert.

In effect from Tuesday 07/21 4:10 PM MDT – Wednesday 07/22 4:00 PM MDT

Issued by NWS Denver CO

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 Tuesday July 21 to 400 PM Wednesday July 22

IMPACTS...Ozone Action Day Alert is now in effect for the Front Range Urban Corridor. Hot and sunny weather with limited chances for afternoon storms will allow ozone concentrations to reach the Unhealthy for Sensitive Groups category on Tuesday and Wednesday. On Tuesday elevated ozone is possible in the Denver Metro area, Fort Collins, Greeley, and surrounding areas. On Wednesday the highest ozone is expected to be confined to locations within the Denver Metro area. 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. Wednesday, July 22, 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.


Areas Impacted

  • Arapahoe, CO
  • Larimer, CO
  • Jefferson, CO
  • Denver, CO
  • Douglas, CO
  • Boulder, CO
  • Adams, CO
  • Weld, CO
  • Broomfield, CO

Tips to Stay Safe

When an Air Quality Alert is active for your location: 

  • Check the air quality levels in your area at airnow.gov
  • Limit your time outdoors, especially if you are at higher risk. This includes seniors, children, or those with asthma or other health conditions. 

Briefings

No recent briefing available

From the Forecaster

Tonight's Forecast

Created by the NWS Denver/Boulder WFO

Scattered showers and thunderstorms will continue across portions of the forecast area this evening with mild temperatures expected. Storm coverage is expected to increase and expand Wednesday and Thursday as deeper monsoonal moisture spreads across the lower elevations. Wednesday will remain hot, but temperatures will cool a few degrees Thursday, bringing some relief from the heat.

Probability of Precipitation through Thursday. Overnight lows tonight: Estes Park: 53, Fort Collins: 65, Greeley: 68, Granby: 47, Kremmling: 48, Breckenridge: 48, Denver: 68, Boulder: 65, Bennett: 68, Fort Morgan: 68, Sterling: 67, Julesburg: 66, Limon: 58

Seven-day Weather Risk Overview

The graphic shows the daily risk summary for 7 days. Daily risk is based on highest risk factor for that day.

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Weather Forecasting Office

Denver/Boulder Forecast Office

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