Hurricane evacuation

Hurricane evacuation is the immediate and rapid movement of people away from the threat or actual occurrence of a hurricane. Local authorities in a predicted hurricane path often recommend or order evacuation of designated flood zones.

Some jurisdictions, such as Pinellas County, Florida, use the output from the Sea, Lake, and Overland Surge from Hurricanes (SLOSH) storm surge model developed by the U.S. Federal Emergency Management Agency (FEMA) to create their evacuation zones. These zones loosely correspond to the maximum expected storm surge expected during a category of hurricane. Since these evacuation maps are used by the general public and a more static nature is desirable, some minor averaging or ranging of data is performed before creating the maps. Changes in variables such as mean high-tide, forward speed and direction of the hurricane, and central pressure all affect the output of the SLOSH model.

The longer a person has lived in a coastal area, the less likely they are to evacuate. Hurricanes have a longer warning time than most disasters, but details of strength and track are only educated guesses. Official warnings, as with other scenario planning, are based on a worst case, which is not the most probable case. Thus, hurricanes can be predicted to hit a coastal town many times without the town ever actually experiencing the brunt of a storm. When this more probable case happens a number of times, people tend to take evacuation orders less seriously.

If evacuation orders are given too early, the hurricane can change course and leave the evacuated area unscathed. People may think they have weathered hurricanes before, when in reality the hurricane didn't hit them directly, giving them false confidence. Those who have lived on the coast for ten or more years are the most resistant to evacuating. [3]

Despite mandatory evacuation orders, many people did not leave New Orleans, as Hurricane Katrina approached. Even after the city was flooded and uninhabitable, some people still refused to leave their homes.

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