2 Thunderstorms * a small intense weather system * formed along cold fronts* warm moist unstable air near the earth’s surface rises (convection)* form cumulonimbus clouds* clouds can reach 40,000 feet tall!
7 Lightning* an electric discharge that occurs between positive and negative charges* lightning can happen between clouds or clouds and the earth* lightning causes the air to expand and contract rapidly to create thunder* lightning can be 33,000*C that’s hot!*lightning kills more people than other storms …Florida and Africa have the most strikes!
10 Hurricanes * Tropical weather system Low pressure * winds at least 120 km/hr* form over warm ocean water* called typhoon in the Pacific ocean* called Hurricane in the Atlantic Ocean* called Cyclone in the Indian Ocean* formed by thunderstorms over warm tropical waters …winds traveling in different directions meet and cause spin
32 Tornadoes * happen in only 1% of thunderstroms * a small spinning cloud with high speed winds that are a low pressure* forms from a funnel cloud poking out the bottom of a cumulonimbus cloud along a cold front where it collides with warm moist air* 75% of the worlds tornadoes occur in the United States