Educational worksheet about air masses, including a map of the United States for labeling different air mass types.

- Air masses are large bodies of air with similar temperature and humidity characteristics.
- They form over source regions, such as oceans or continents, and take on the properties of those regions.
- Air masses are classified by their source region (polar or tropical) and whether they form over land (continental) or water (maritime).
- When air masses move, they bring their weather conditions to new areas.
- Fronts form where different air masses meet, often causing changes in weather like clouds, wind, or precipitation.