Hurricane Harvey has been strengthening rapidly as it rolls across the southern Gulf of Mexico, headed for a likely landfall somewhere along the Texas coast.
According to the National Hurricane Center, the storm could be a Category 3, or major hurricane, before or as it makes landfall.
In its latest forecast, the NHC warns that Harvey is “quickly strengthening and forecast to be a major hurricane when it approaches the middle Texas Coast … life-threatening storm surge and freshwater flooding expected.”
What is storm surge, how does it happen and why should you be wary of it? Here is a quick look at storm surge.
What is storm surge?
A storm surge is water pushed inland as a hurricane advances and makes landfall.
How does it form?
Imagine a bowl of water. Put your hand in the middle of the bowl and cup it. Now slowly push your hand toward the edge of the bowl. Those are the same dynamics as storm surge. The ocean water is pushed by winds and waves, and is also sucked into the air near the eye of the hurricane by low pressure.
Is it a “wall of water” that rushes in?
Rarely. It is usually a rise of water that can happen quickly, moving at the same rate as the forward speed of a hurricane.
How powerful is it?
Very powerful. Only 1 cubic yard of sea water weighs 1,728 pounds. A 6-inch surge can knock a person down.
How dangerous is it?
Storm surge kills more people in a hurricane than all other components of the storm. The overwhelming majority of deaths in the 10 deadliest U.S. landfalling hurricanes were the result of storm surge.
How can I stay safe?
Get away from it. A surge 1 foot deep can take a car off a road. Get out early, because the surge can begin up to 24 hours before landfall. During Hurricane Katrina, people stayed in their homes and died there when the surge filled their homes with water and they could not escape. Also, don’t leave pets at home. Many animals died when people left them in their homes during Hurricane Katrina.