1. Chapter 2 OBSERVING WEATHER AAAAIR PRESSURE: The push of the air in all directions against its surroundings. BBBBAROMETER: A device used to measure air pressure. HHHHIGH PRESSURE AREAS: An area of higher air pressure than that of the surrounding air. LLLLOW PRESSURE AREAS: An area of lower air pressure than that of the surrounding air. WWWWIND VANE: A device, often shaped like an arrow, used to show the direction of the wind.

2. WWWWINDSOCK: A device used to show wind direction, consisting of a cloth bag that is open at both ends and hung on a pole. AAAANEMOMETER: A device used to measure the speed of the wind. HHHHUMIDITY: The amount of water vapor in the air. RRRRELATIVE HUMIDITY: The amount of water vapor present in the air at a given temperature compared to the maximum amount that the air could hold at that temperature. EEEEVAPORATE: To change from liquid to a gas.

3. CCCCONDENSES: To change from a gas to a liquid. CCCCLOUD: A mass of tiny droplets of water that condensed from the air. PPPPRECIPITATION: Any form of water that falls from clouds to Earth’s surface. RRRRAIN GAUGE: A device for measuring precipitation.