1. And, we’re not talking about the University of Miami.
Hurricanes
And, we’re not talking about the University of Miami.

2. What is a hurricane?
Hurricanes are examples of tropical cyclones found in the western North Atlantic. This type of storm is known in other locations as a cyclone or a typhoon.
Hurricanes begin life as an area of low pressure that forms off the western shore of sub-Saharan Africa.
This area is known as the “hurricane nursery”.
These low pressure systems move westward due to prevailing winds.
As they move across warm equatorial waters, some gain strength and merge with other lows to form tropical depressions.
Due to the Coriolis Effect, low pressure systems rotate in a counter-clockwise manner in the Northern Hemisphere. (opposite in Southern Hemisphere)

3. Hurricane Nursery

4. What is a hurricane? (continued)
As these depressions develop, they are identified and assigned a number. If the system continues to grow into a tropical storm, a name is assigned.
There exist six lists of 21 names used to identify hurricanes. They are used in sequential years.
If a hurricane causes significant monetary damages or loss of life, the name is retired out of sensitivity for those affected.

5. 2018 Hurricane Names Alberto Beryl Chris Debby Ernesto Florence
Gordon Helene Isaac
Joyce Kirk Leslie
Michael Nadine Oscar
Patty Rafael Sara
Tony Valerie William

6. Select retired Hurricane names
Camille (1969) – struck Gulf Coast.
Agnes (1972) – struck mid-Atlantic seaboard.
Andrew (1992) – struck southern Florida.
Floyd (1999) – struck mid-Atlantic seaboard.
Isabel (2003) – struck mid-Atlantic seaboard.
Katrina (2005) – struck Florida and Gulf Coast.

7. Classification of Hurricanes
Based on wind strength.
Saffir-Simpson scale.
Damages increase exponentially as wind speed increases in a linear fashion.

8. Hurricane structure
Hurricanes are orderly storms with predictable and consistent organization.
The “eye” of a hurricane is its most notable feature. The eye is the central feature and is an area of calm winds and few, if any, clouds. The storm circulates around this area, which possesses the lowest atmospheric pressure in the system.
The “eye wall” is the a ring of very powerful thunderstorms which are closest to the eye. Due to angular momentum, the winds in this region are the strongest and do the most damage.
“Rainbands” are rings of thunderstorms that spiral in towards the eye. As they move toward the eye, they often merge and gain strength.

9. Hurricane structure (continued)

10. Hurricane structure (continued)

11. Hurricane lifespan
Formation begins in tropical waters off west coast of sub-Saharan Africa.
Low pressure system begins trek westward over warm tropical waters (up to 1 week).
Storm gains strength and begins to veer toward north, due to influence of westerly winds (up to 1 week).
If the storm continues over warm water (Gulf Stream), it will continue to gain strength (2-3 days).
Once the storm makes landfall, it will begin to dissipate (may take 5 days to completely dissipate).

12. Irma and Andrew
When Hurricane Andrew hit South Florida in 1992, it cut a wide swath of destruction across the state.
63,000 homes were destroyed, more than $26.5 billion in damages were estimated, and 65 people were killed.
Irma makes Andrew look like a typical thunderstorm.

13. Florence
Hurricane Florence has been downgraded to a Category 2 storm (as of this morning).
The storm still packs a punch, with winds of 70 mph extending 185 miles from the eye. Within a radius of 80 miles, winds of 90+ mph are being recorded.
The storm surge is expected to be up to 13 feet.
The land where Florence is expected to come ashore is below 13 feet of sea level up to 20 miles inland.
Rainfall amounts of up to 2 feet are possible.

14. Florence from space