Weather Alert in Colorado
Air Quality Alert issued July 17 at 4:10PM MDT by NWS Denver CO
AREAS AFFECTED: Adams, CO; Larimer, CO; Douglas, CO; Arapahoe, CO; Weld, CO; Broomfield, CO; Jefferson, CO; Boulder, CO; Denver, 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 Cumulonimbus Clouds?
Home - Education - Cloud Types - Cumulonimbus Clouds
Next Topic: Cumulus Clouds
The final form taken by a growing cumulus cloud is the
cumulonimbus cloud, which is very tall and dense.
The tower of a cumulonimbus cloud can soar 23 km into the atmosphere, although
most commonly they stop growing at an altitude of 6 km.
Even small cumulonimbus clouds appear very large in comparison to other cloud types.
They can signal the approach of stormy weather, such as thunderstorms or blizzards.
Next Topic: Cumulus Clouds
Weather Topic: What is Drizzle?
Home - Education - Precipitation - Drizzle
Next Topic: Evaporation
Drizzle is precipitation in the form of water droplets which are
smaller than raindrops.
Drizzle is characterized by fine, gently falling droplets and typically does not
impact human habitation in a negative way. The exception to this is freezing drizzle,
a condition where drizzle freezes immediately upon reaching earth's surface.
Freezing drizzle is still less dangerous than freezing rain, but can
potentially result in hazardous road conditions.
Next Topic: Evaporation
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