2. Air Masses and Fronts Air Mass: a large body of air that has about the same temperature and humidity throughout It can be warm or cold Can have a little or lot of water vapor
4. Air Masses do not mix together! The line where two air masses meet is called a front.
5. Cold Front When a cold front moves and collides with a warm front, the warm air rises quickly and cools rapidly, causing huge storm clouds to build up. Rain or snow may fall. Thunder and lightning may also occur. Cold Fronts move quickly, so the storm may not last very long.
6. Warm Front When a warm front collides with a cold front, the warm air slides slowly upward over the cold air mas. As the warm air rises, it cools and forms clouds. Clouds are feathery and form high. Thicker clouds that form lower n the sky follow. A gentle rain or snow is produced. When the warm front passes, warm, mild weather follows.
7. Tracking and Predicting Weather Forecast: prediction of what the weather will be like for the next few days. Meteorologist: Person who studies the weather
8. What Meteorologists Track High and Low Temperatures Humidity Air Pressure Precipitation Air Masses Fronts Wind Speed and Direction
10. National Weather Service A government agency that collects information about weather. Use advanced tools, such as satellites above the earth to collect information from all over the world