| A | B |
|---|
| 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 | Weather |
| Amount of water vapor held in the air | Humidity |
| Measure of the amount of moisture held in the air compared with the amount it can hold at a given temperature; can range from 0 percent to 100 percent | Relative humidity |
| Temperature at which air is saturated and condensation forms | Dew point |
| A stratus cloud that forms when air is cooled to its dew point near the ground | Fog |
| Water falling from clouds - including rain, snow, sleet, and hail - whose form is determined by air temperature | Precipitation |
| 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 | Air mass |
| Boundary between two air masses with different temperatures, density, or moisture; can be cold, warm, occluded, and stationary | Front |
| Violent, whirling windstorm that crosses land in a narrow path and can result from wind shears inside a thunderhead | Tornado |
| Large, severe storm that forms over tropical oceans, has winds of at least 120 km/h, and loses power when it reaches land | Hurricane |
| Winter storm that lasts at least three hours with temperatures of -12 degrees C or below, poor visibility, and winds of at least 51 km/h | Blizzard |
| Person who studies weather and uses information from Doppler radar, weather satellites, computers and other instruments to make weather maps and provide forecasts | Meterologist |
| Indicates weather conditions at a specific location, using a combination of symbols on a map | Station model |
| Line drawn on a weather map that connects points having equal temperature | Isotherm |
| Lines drawn on a weather map that connect points having equal atmospheric pressure; also indicate the location of high and low pressure areas and can show wind speed | Isobar |
| Instrument used to detect the barometric pressure | Barometer |
