Weather Alerts for Denver

Issued by the National Weather Service

Air Quality Alert  AIR QUALITY ALERT   Air Quality Alert
DENVER

Areas Affected:
Arapahoe, CO - Jefferson, CO - Weld, CO - Denver, CO - Broomfield, CO - Douglas, CO - Boulder, CO - Adams, CO - Larimer, CO
Effective: Fri, 9/5 8:10am Updated: Fri, 9/5 12:00pm Urgency: Unknown
Expires: Fri, 9/5 4:00pm Severity: Unknown Certainty: Unknown

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

WHAT...Action Day for Particulates.

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

WHEN...400 PM Thursday September 04 to 400 PM Friday September 05

IMPACTS...Action Day for Particulates is now in effect for the
Front Range Urban Corridor.  Elevated levels of fine particulate
matter will remain in the Front Range on Friday due to lingering
smoke. Ozone Levels are expected to remain in the Good to Moderate
range.   For Colorado air quality conditions, forecasts, and
advisories, visit:
https://www.colorado.gov/airquality/colorado_summary.aspx   If
possible, please help us reduce pollution by limiting driving gas
and diesel-powered vehicles until at least 4 PM Friday, September
5, 2025.

HEALTH INFORMATION...If smoke is thick or becomes thick in your
neighborhood you may want to remain indoors. This is especially
true for those with heart disease, respiratory illnesses, the very
young, and older adults. Consider limiting outdoor activity when
moderate to heavy smoke is present. Consider relocating
temporarily if smoke is present indoors and is making you ill. If
visibility is less than 5 miles in smoke in your neighborhood,
smoke has reached levels that are unhealthy.

Air Quality Alert  AIR QUALITY ALERT   Air Quality Alert
DENVER

Areas Affected:
Jefferson, CO - Douglas, CO - Arapahoe, CO - Weld, CO - Broomfield, CO - Boulder, CO - Larimer, CO - Denver, CO - Adams, CO
Effective: Thu, 9/4 4:10pm Updated: Fri, 9/5 12:00pm Urgency: Unknown
Expires: Fri, 9/5 4:00pm Severity: Unknown Certainty: Unknown

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

WHAT...Action Day for Multiple Pollutants.

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

WHEN...400 PM Thursday September 04 to 400 PM Friday September 05

IMPACTS...Action Day for Multiple Pollutants is now in effect for
the Front Range Urban Corridor.  Hot, dry weather combined with
out-of-state wildfire smoke will allow ozone and fine particulate
concentrations to reach the Unhealthy for Sensitive Groups
category at times both Thursday and Friday.   For Colorado air
quality conditions, forecasts, and advisories, visit:
https://www.colorado.gov/airquality/colorado_summary.aspx   If
possible, please help us reduce pollution by limiting driving gas
and diesel-powered vehicles until at least 4 PM Friday, September
5, 2025.

HEALTH INFORMATION...If smoke is thick or becomes thick in your
neighborhood you may want to remain indoors. This is especially
true for those with heart disease, respiratory illnesses, the very
young, and older adults. Consider limiting outdoor activity when
moderate to heavy smoke is present. Consider relocating
temporarily if smoke is present indoors and is making you ill. If
visibility is less than 5 miles in smoke in your neighborhood,
smoke has reached levels that are unhealthy.