What is a Hurricane?
A hurricane is a large and powerful storm that can be hundreds of miles across! A hurricane has strong winds spiraling inward and upward, and can move at speeds of 75 to 200 mph. For instance, at peak intensity Hurricane Ian was a Category 4 hurricane, with maximum sustained winds of 155 miles per hour! The highest and most dangerous category of hurricane is Category 5, with maximum sustained winds of over 155 mph.
What makes a hurricane special is that it rotates around the “eye” of the storm, which is the calmest part. Hurricanes rotate in a counter-clockwise direction in the Northern Hemisphere and clockwise direction in the Southern Hemisphere. You need three things for a hurricane to form: warm water, cooler air, and wind.
Typically, hurricanes form over warm ocean waters of at least 80°F. That combined with the cooler air of early fall sets things up for a hurricane. When ocean waters are warm and the air above is cool, AND there’s a wind that’s blowing in the same direction and at the same speed, this starts forcing air upward from the ocean surface. The winds start to flow outward above the storm allowing the air below to rise, giving the hurricane its strength and its shape. Then something called the Coriolis Force gives hurricanes that special spin you see! Atlantic hurricanes typically occur between June and November.
How are Hurricanes Classified?
Hurricanes are classified into five categories, based on their wind speeds and potential to cause damage.
Category 1: Winds 75-95 mph with minimal damage
Category 2: Winds 96-110 mph with moderate damage
Category 3: Winds 111-130 mph with extensive damage
Category 4: Winds 131-155 mph with extreme damage
Category 5: Winds 155+ mph with catastrophic damage
Sometimes a hurricane will start with a high classification of Category 5 but then drop once it hits land. For instance, Hurricane Matthew started off as a Category 5 but was considered Category 4 once it made landfall in Florida. Once a hurricane hits land it loses strength, i.e. decreases in category, because of cool temperatures, a lack of moisture, and/or friction. Moisture is what fuels a hurricane!
What are some Famous Hurricanes?
1992 – Hurricane Andrew – Category 5
1999– Hurricane Floyd – Category 2
2005– Hurricane Katrina – Category 5
2012– Hurricane Sandy – Category 3
2016– Hurricane Matthew – Category 5/4
2018– Hurricane Michael – Category 5
2022– Hurricane Ian – Category 4
Check out this cool video! Make a hurricane in a bowl at home so you can see how they work: https://www.youtube.com/watch?v=PRlpLenOcTg
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