Peter glanced over to see Richard's reaction and saw that, like everyone else, Richard was laughing and trying to wipe the water off his face. He was talking it better than Peter had thought he would. "This is fun" Peter whispered.
The voice was talking again, and the screen overhead was changing. " Thunderstorms can form in different ways, " the voice explained. The screen showed a mountain with towering clouds to one side. Rain was falling from the clouds. "As a pocket of air approaches a mountain, it can be forced upward. The air rising in the atmosphere is under less pressure. It begins to cool, and moisture in the air condenses to from clouds. Eventually, a thunderstorm can develop."
"Sounds like the same thing we heard about earlier," commented Richard.
Leah looked at him and shook her head. "No, it's not! The air is forced to rise upward along the mountain. In the first storm, cold air pushed the warm air upwards."
" shhh! " whispered several student nearby.
" Thunderstorms may also be caused by moving air masses,"