Hurricanes, Floods, and Blizzards

1. Hurricanes, Floods, and Blizzards

2. Tropical Storms Larger • ______, but less intense than tornadoes. • ____ pressure areas. • Rotates __________________ in the northern hemisphere. • Average _______ miles in diameter. • Last for days or weeks. • Wind speed is ____ to ____ mph. • _______ winds and heavy rain. Low counterclockwise 400 38 74 Strong

3. Hurricane Formation hurricane • In order for a ___________ to form, there must be a supply of warm, moist air for a long period of time. • ___________ that evaporates from the ocean condenses in the clouds. • This process releases heat. • The _______ fuels the development of a hurricane. • When hurricanes reach ________ there is no longer a water source and the hurricane weakens. Water heat land

4. How do we know what it is?

5. Hurricane • Around the United States and the Caribbean it is called a ___________. • In the western Pacific Ocean it is called a ___________. • In the Indian Ocean it is called a ___________. • A tropical storm is officially a hurricane when it reaches surface winds of ____ mph. • This is the most __________ storm on Earth. hurricane typhoon cyclone 75 powerful

6. What is it called?

7. Hurricane Near the equator Atlantic Ocean • Tropical storms form in the tropics (__________________). • In the ________________ the formation is off the coast of Africa.

8. Parts of a Hurricane Eye • _____- The center of the hurricane. • Cloud-free • Sinking, dry air in middle • 20-40 miles wide • Thick, ________________ clouds spiral outward from the eye. cumulonimbus

9. Parts of a Hurricane

10. Hurricane effects Storm surge • _______________- When the storm reaches shore, strong winds and abnormally high water level caused by low pressure create a storm surge that floods coastal areas. • Hurricane Katrina had a storm surge of ___ feet. (New Orleans, 2005) 28

11. Hurricane categories Saffir-Simpson Scale

12. Tropical Storm and Hurricane names tropical storm • When the storm becomes a ________________ it is given a name. • Names in alphabetical order. (Not Q, U, X, Y, Z) • If there are more than 21 storms in a year, the Greek alphabet is used. (Alpha, Beta, Gamma, Delta….) • Lists are reused every six years. • When there is major death and destruction the name is retired.

13. Tropical Storm and Hurricane names • g

14. Tropical Storm and Hurricane forecast by Colorado State University June November • Hurricane season is _____ through ____________.

15. Hurricanes in the United States

16. Hurricane Maria – Puerto Rico 2017 Category 4 • ____________ when it hit Puerto Rico. • Sustained winds of 175 mph. • Caused $90 billion in damage. • 3,057 died. • Still rebuilding.

17. Hurricane Maria – Puerto Rico 2017

18. Hurricane Katrina – New Orleans and nearby 2005 • Category ___. • 28 feet storm surge. • Caused $125 billion in damage. • ~1,600 died. • 80% of New Orleans was flooded. 5

19. Hurricane Katrina – New Orleans and nearby 2005

20. Floods capacity • When a river exceeds the ___________ of its channel, it overflows its banks. • Floods are the most common and most _______________ of all geologic hazards. • The stream overflows onto low-lying adjacent land called the _____________. destructive Floodplain

21. Causes of Floods • Rivers flood because of the ____________. • Rapidly ______________ and/or _____________ with heavy rains over a large region cause most floods. • Floods may also be caused when ________ and _________ break. weather melting snow major storms dams levees

22. Flood Control levees • Artificial ____________ may be built. Earthen mounds built on the banks of a river to increase the volume of the channel. • The stream may rise above the ___________ and be contained in the levees. floodplain

23. Flood Control levee • If the _______ is breached the entire stream would flow out and cause a huge flood.

24. Flood Control Flood-control dams • _____________________ are built to store floodwater and then let it out slowly.

25. Flood Control Channelization • ________________ involves altering a stream channel in order to speed the flow of water to prevent it from reaching flood height. • This may be clearing a channel of obstructions or dredging a channel to make it wider or deeper.

26. Flash Floods Flash floods torrential • ____________ are local floods of great volume and short duration. • Flash floods usually result from _________ rains associated with slow-moving severe thunderstorms or a sequence of smaller storms. • More common in the ___________ where the slope is steep. • Flash floods are the leading cause of storm related deaths. More than half of the deaths are auto related. • Large rivers __________ have flash floods. mountains do not

27. Blizzard Blizzard • _________ - A dangerous winter storm with high wind, snow, and low visibility. • A winter storm is considered a blizzard when: • Sustained _______ of 35 mph. • Falling and/or blowing snow causing ___________ of less than ¼ mile. • The conditions must last at least ______________________. wind visibility 3 consecutive hours

28. Blizzard 27.5 • The January 23, 2016 blizzard in New York City was the largest snowfall on record in Central Park. There was an accumulation of _____ inches of snow, with blizzard conditions lasting for seven hours during the peak of the storm!

29. Largest blizzards in Chicago • January 26-27, 1967- There was 23 inches of snow. • January 1-3, 1999- There was 21.6 inches of snow and 20 below zero temperatures. • Jan 31 – Feb 2, 2011- There was 21.2 inches of snow. 900 cars and buses were stranded on Lake Shore Drive. • January 12-14, 1979- There was 20.3 inches of snow.

30. Blizzard of 1967

31. Blizzard of 2011