Why Storm Surges Can Be So Harmful


Hurricanes and tropical storms are characterized by their strong winds. But the storm surges they produce can often prove just as devastating in coastal communities.

Hurricane Ida is said to trigger dangerous storm surges in parts of Louisiana and Mississippi.

Storm surge is defined as an abnormal rise in sea level caused by a storm beyond the predicted astronomical tide. The waves are created by sea water moving inland and driven by the force of the wind.

In the open ocean, hurricanes can smash the water without creating a wave. But near the coast, the shallower water is blown inland and threatens property and life.

The deepest water will occur along the immediate coast in areas with onshore winds, where the surge is accompanied by large and dangerous waves, the National Hurricane Center said.

Flooding-related floods depend on the timing of the high tide and the tidal cycle and can vary widely over short distances, the center said.

In 2008, Ike, a Category 2 hurricane that hit land near Galveston Island, Texas, generated waves 15 to 20 feet above normal tide, the center said. Property damage was estimated at $ 24.9 billion.

The National Hurricane Center said areas placed under storm surge warning are at risk of “life-threatening flooding.” People in these areas should follow all evacuation instructions from local officials, the center said.