| A | B |
|---|
| troposhpere | The bottom layer of the Earth's atmosphere. |
| air mass | A large body of air that has the same characteristics throughout. |
| air pressure | The weight of air pressing down on an area. |
| front | The border between two air masses that collide. |
| warm front | When a warm air mass moves into an area of cooler air. |
| cold front | When a cold air mass moves into an area of warmer air |
| cirrus clouds | igh clouds that signal a warm front is comeing |
| forecast | a prediction of what the weather will be like in the future |
| weather balloon | Carries a package of instruments that records data about temperature, air pressure and humidity. |
| weather map | Shows data about recent weather conditions across a large areas. |
| thunderstorm | A very strong storm with a lot of rain, thunder and lightening. |
| hurricane | Large spiarling storm systems that can be as much as 600 km across. |
| tropical storm | When winds of a tropical depression reach a constant speed of 63km/hr. |
| tornado | An intense windstorm that often forms within a severe thunderstorm. |
| continental polar air | air mass that forms over Alaska and Norther Canada. Air is Cold and dry |
| maritime polar air | Air that comes from the northern part of either the Pacific or Atlantic Ocean. The air is cool and moist. |
| maritime tropical air | Air that comes from the southern Pacific Ocean or the Gulf of Mexico. Air is warm and moist. |
| continental tropical air | The aire that comes from the deserts of Mexico and south west US. Air is hot and dry. |
| meteorologist | Scientist who studies the weather. |
| anemometer | measures wind speec |
| barometer | measures air pressure |
