Weather Alert in Colorado
Air Quality Alert issued July 17 at 5:10PM MDT by NWS Denver CO
AREAS AFFECTED: Arapahoe, CO; Broomfield, CO; Jefferson, CO; Denver, CO; Larimer, CO; Douglas, CO; Adams, CO; Boulder, CO; Weld, CO
DESCRIPTION: 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 Thursday July 17 to 1200 AM Friday July 18 IMPACTS...Ozone Action Day Alert is now in effect for the Front Range Urban Corridor. On Thursday, stagnant weather will allow ozone to reach the Unhealthy for Sensitive Groups category on Thursday. The highest concentrations are expected in southern and western portions of the Denver Metro area. Unsettled weather will limit ozone development on Friday, and Good to Moderate ozone is expected. 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 midnight Thursday night, July 17, 2025. 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.
INSTRUCTION: N/A
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Weather Topic: What are Altocumulus Clouds?
Home - Education - Cloud Types - Altocumulus Clouds
Next Topic: Altostratus Clouds
Similar to cirrocumulus clouds, altocumulus clouds are
characterized by cloud patches. They are distinguished by larger cloudlets
than cirrocumulus clouds but are still smaller than stratocumulus clouds.
Altocumulus clouds most commonly form in middle altitudes (between 2 and 5 km)
and may resemble, at times, the shape of a flying saucer.
These uncommon formations, called altocumulus lenticularis, are created by uplift
in the atmosphere and are most often seen in close proximity to mountains.
Next Topic: Altostratus Clouds
Weather Topic: What are Cirrocumulus Clouds?
Home - Education - Cloud Types - Cirrocumulus Clouds
Next Topic: Cirrostratus Clouds
Cirrocumulus clouds form at high altitudes (usually around 5 km)
and have distinguishing characteristics displayed in a fine layer of
small cloud patches. These small cloud patches are sometimes referred to as
"cloudlets" in relation to the whole cloud formation.
Cirrocumulus clouds are formed from ice crystals and water droplets. Often, the
water droplets in the cloud freeze into ice crystals and the cloud becomes a
cirrostratus cloud. Because of this common occurrence, cirrocumulus cloud
formations generally pass rapidly.
Next Topic: Cirrostratus Clouds
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