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 4 p.m. Friday, July 18, 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 Cumulus Clouds?
Home - Education - Cloud Types - Cumulus Clouds
Next Topic: Drizzle
Cumulus clouds are fluffy and textured with rounded tops, and
may have flat bottoms. The border of a cumulus cloud
is clearly defined, and can have the appearance of cotton or cauliflower.
Cumulus clouds form at low altitudes (rarely above 2 km) but can grow very tall,
becoming cumulus congestus and possibly the even taller cumulonimbus clouds.
When cumulus clouds become taller, they have a greater chance of producing precipitation.
Next Topic: Drizzle
Weather Topic: What is Evaporation?
Home - Education - Precipitation - Evaporation
Next Topic: Fog
Evaporation is the process which returns water from the earth
back to the atmosphere, and is another crucial process in the water cycle.
Evaporation is the transformation of liquid into gas, and it happens because
molecules are excited by the application of energy and turn into vapor.
In order for water to evaporate it has to be on the surface of a body of water.
Next Topic: Fog
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