| A | B |
|---|
| Air Mass | A large body of air, with one uniform temperature and moisture content. |
| mP | Maritime Polar |
| mT | Maritime Tropical |
| cP | Continental Polar |
| cT | Continental Tropical |
| Polar Air Masses | Continental Polar Canadian, Maritime Polar Pacific, and Maritime Polar Atlantic. |
| Tropical Air Masses | Continental Tropical, Maritime Tropical Gulf, Maritime Tropical Atlantic, and Maritime Tropical Pacific. |
| Front | A boundaries that form between air masses. |
| Cold Front | When a cold air mass overtakes a warm air mass. |
| Squall Line | A heavy line of thunderstorms that usually follows a fast-moving cold front. |
| Warm Front | When a warm air mass overtakes a cold air mass. |
| Occluded Front | When a cold front overtakes a warm front, lifting a the warm air completely off the ground. |
| Stationary Front | The front formed between the air masses. |
| Polar Front | The boundary at which the cold polar air meets the warmer air of the middle latitudes. |
| Wave Cyclones | The waves along the boundary of a polar front that are the beginnings of a low-pressured storm center. |
| Anticyclone | A storm that spirals outward from a high pressure center. |
| Hurricane | A sever tropical storm. |
| Typhoon | A hurricane that occurs in the western North Pacific Ocean. |
| Thunderstorm | A storm accompanied by thunder, lightning, and strong winds. |
| Tornado | The smallest, most violent, and shortest-lived sever storm. |
| Waterspout | Tornados that occur over the ocean. |
| Bimetal Thermometer | An instrument that measures temperature, it consists of a bar made of two strips of different metals that curves when heated and straightens when cooled. |
| Thermograph | An instrument that measures temperature changes by recording the movement of the bar of a bimetal thermometer. |
| Electrical Thermometer | An instrument that measures temperature based on the increased flow of electricity through certain materials when the materials are heated. |
| Anemometer | Measures windspeed. |
| Wind Vane | Shows the wind direction. |
| Radar | An electronic device that transmits pulses of radio waves in the form of a beam. |
| Station Model | A cluster of symbols on a map that show the conditions at a weather station. |
| Cloud Seeding | When freezing nuclei are added to supercooled clouds, causing rain to fall. |
| Isobars | The lines drawn to connect points of equal atmospheric pressure. |
