1. Weather Maps and Atmospheric Effects

2. Fronts

3. Humidity

4. Water and the Atmosphere Most water in the air is evaporated from the oceans This water vapor causes clouds, rain, storms, etc Measure of water vapor in the air is called humidity Higher the temp, more water vapor air can hold

5. Condensation Point at which air cools and can hold no more water vapor. Evaporated gas changes back to liquid droplets Can become precipitation if large enough

6. Four Common forms of Precipitation Rain Snow Sleet Hail

7. Storms Occur under low pressure conditions At any moment, about 2,000 storms are taking place on Earth In the U.S., storms are most common along polar and westerly wind boundaries