Weather Alert in Illinois

Recent Locations: Xenia, OH   Cameron, MO   Hartsburg, IL  
Current Alerts for Hartsburg, IL: Heat Advisory

Extreme Heat Watch issued June 20 at 2:03AM CDT until June 24 at 9:00PM CDT by NWS St Louis MO

AREAS AFFECTED: Jersey; Madison; St. Clair; Monroe; St. Charles; St. Louis; St. Louis City; Jefferson

DESCRIPTION: * WHAT...Dangerously hot conditions with heat index values up to 109 possible. * WHERE...In Illinois, Jersey IL, Madison IL, Monroe IL, and Saint Clair IL Counties. In Missouri, Jefferson MO, Saint Charles MO, Saint Louis City MO, and Saint Louis MO Counties. * WHEN...From Saturday afternoon through Tuesday evening. * IMPACTS...Heat related illnesses increase significantly during extreme heat and high humidity events.

INSTRUCTION: Drink plenty of fluids, stay in an air-conditioned room, stay out of the sun, and check up on relatives and neighbors. Do not leave young children and pets in unattended vehicles. Car interiors will reach lethal temperatures in a matter of minutes. Monitor the latest forecasts and warnings for updates. If you do not have air conditioning in your home or lack shelter, you can call 211 for assistance locating appropriate shelter from the heat.

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Current U.S. National Radar--Current

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National Weather Forecast--Current

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North America Water Vapor (Moisture)

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Weather Topic: What is Condensation?

Home - Education - Precipitation - Condensation

Condensation Next Topic: Contrails

Condensation is the process which creates clouds, and therefore it is a crucial process in the water cycle. Condensation is the change of matter from a state of gas into a state of liquid, and it happens because water molecules release heat into the atmosphere and become organized into a more closely packed structure, what we might see as water droplets.

Water is always present in the air around us as a vapor, but it's too small for us to see. When water undergoes the process of condensation it becomes organized into visible water droplets. You've probably seen condensation happen before on the surface of a cold drink!

Next Topic: Contrails

Weather Topic: What are Cumulonimbus Clouds?

Home - Education - Cloud Types - Cumulonimbus Clouds

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

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