| A | B |
|---|
| Weather | The state of the atmosphere at a specific time and place, determined by factors including air pressure, amount of moisture in the air, temperature, wind, and precipitation |
| Humidity | The amount of water vapor held in the air |
| Dew point | The temperature at which air is saturated and condensation forms |
| Fog | A stratus cloud that forms when air is cooled to its dew point near the ground |
| Precipitation | Water falling from clouds – including rain, snow, sleet, and hail – whose form is determined by air temperature |
| Air mass | A large body of air that has the same characteristics of temperature and moisture content as the part of Earth’s surface over which it formed |
| Front | The boundary between two air masses with different temperatures, density, or moisture |
| Tornado | A violent, whirling windstorm that crosses land in a narrow path and can result from wind shears inside a thunderhead |
| Hurricane | A large, severe storm that forms over tropical oceans, has winds of at least 119 km/h (74 mph), and loses power when it reaches land |
| Blizzard | A winter storm that lasts at least three hours with temperatures of -12°C (10°F) or below, poor visibility, and winds of at least 51 km/h (30 mph) |
| Meteorologist | A scientist who studies weather and uses information from Doppler radar, weather satellites, computers and other instruments to make weather maps and provide forecasts |
| Station model | Indicates weather conditions at a specific location, using a combination of symbols on a map |
| Isotherm | A line drawn on a weather map that connects points having equal temperature |
| Isobar | A line drawn on a weather map that connects points having equal atmospheric pressure |
| Climate | The average weather pattern in an area over a long period of time; can be classified by temperature, humidity, precipitation, and vegetation |
