1. Ms. Twardowski 8 Tan Central Middle School
Hurricanes ! ! !
Ms. Twardowski
8 Tan
Central Middle School

2. Word Splash ! ! ! air pressure temperature wind
climate forecast humidity
dew point migration precipitation

3. FIRST…
A thunderstorm, a tropical depression, a tropical storm, and a hurricane are ALL THE SAME! They are just at varying stages of size and levels of dangerousness.

4. To begin to understand what causes a hurricane you need to know:
When the temperature and dew point are closer together, there is more moisture in the air particles. Usually this happens when the temp. and dew pt. are within FIVE (5) degrees of each other.
This means there humidity is higher and there is a higher chance for precipitation.

5. Also…
When the temp. and dew pt. are further apart, there is LESS moisture in the air particles.
This means the humidity is LOWER.
There is LESS chance for precipitation.

6. Air Pressure…
When the air pressure is low and/or falling…it means it is going toward “bad” weather.
When it’s rising and/or high, it’s going toward “good” weather. (Example, if it is raining, it will likely stop.)

7. What causes a hurricane (6 components)?...
1. Warm ocean water (at least 80 degrees Fahrenheit).
2. Large DECREASE of temperature with altitude (height).
3. Moisture present in the air (up to a high altitude)

8. What causes a hurricane?...
4. Pre-existing (already there) near surface disturbance (for example, a Low-pressure system like a thunderstorm).

9. What causes a hurricane?...
5. Vertical wind shear
6. Minimum of 300 miles from the Equator so the “Coriolis Effect/Force” can take effect (see picture at left).

10. Hurricanes…

11. As seen from a satellite…

12. This is the symbol for a hurricane…

13. It’s coming. BTW, a hurricane and a tornado are the same thing
It’s coming!...BTW, a hurricane and a tornado are the same thing! Tornadoes happen over land, hurricanes over water.

14. Hurricanes…
MOST of the damage is caused by “storm surge”…when huge waves are pushed up onto shore.

15. Hurricanes…
It causes flooding and can cause millions of dollars worth of damage. It can also claim lives.

16. The aftermath…
Objects can be thrown long distances! This is VERY dangerous!

17. Hurricane Watches and Warnings…
Watch: is issued when hurricane conditions are possible within 24 to 36 hours.
You should: Have a battery operated radio or tv. Have a full tank of gas. Bring in outdoor objects. Board up windows. Store drinking water. Etc.

18. Hurricane Watches and Warnings…
Warning: Is issued when hurricane conditions (winds of 74 mph or greater, high water, rough seas) are expected in 24 hours or less.
You should: Listen to your radio or tv. Stores valuables in a waterproof container. Avoid elevators. Stay inside, away from windows and glass doors.

19. Hurricane Catgories Category Wind Speed Observed Damage Storm Surge 1
74-95 mph
Branches break off, power lines down
4-5 feet 2
mph
Small trees down, roof tiles blown off
6-8 ft 3
mph
Leaves off trees,trees down,small building damage
9-12 ft 4
mph
Severe damage to windows,roofs,doors,flooding,
13-18 ft 5
over 155 mph
Small buildings destroyed,evacuation required,major damage!
over 18 ft

20. How do they name hurricanes?
Since 1953, in the Atlantic Ocean, tropical storms that reach a sustained wind speed of 39 miles per hour are given a name, such as "Tropical Storm Fran".
The first tropical storm of the year is given the name beginning with the letter "A", the second with the letter "B" and so on through the alphabet (using alternating men’s and women’s names).
Today, the World Meteorological Organization maintains the lists of Atlantic hurricane names. They have six lists which are reused every six years.
Hurricane names that cause MAJOR damage are put on the “Retired List” and are not used again.

21. 2011 Hurricane Season Names
Arlene, Bret, Cindy, Don, Emily, Franklin, Gert, Harvey, Irene, Jose, Katia, Lee, Maria, Nate, Ophelia, Philippe, Rina, Sean, Tammy, Vince, & Whitney
If there are more than 21 hurricanes for this season, names of the letters of the Greek alphabet will be used (Alpha, Beta, Delta, Gamma, etc.)

22. The Beaufort Scale (wind speed)…

23. Beaufort Scale (again)