HOUSTON — As hurricane season ramps up, one of the deadliest hazards of an approaching hurricane is storm surge. According to the National Weather Service, storm surge is an abnormal water level rise generated by a storm over the above astronomical tide. This rise in water level along the immediate coast can cause extreme flooding, especially when storm surge is combined with high tide. Water inundation could be as high as 20 feet or more, reaching as high as the second floor in some structures along the coast.
During peak storm surge, large waves can bring water and loose debris inland causing more damage, devastation and loss of life. It is important to pay attention to storm surge forecasts and heed evacuation advice from local officials.
What causes storm surge?
As hurricanes are areas of low pressure over open water, onshore winds from the right front quadrant are the areas that will experience the highest amounts of storm surge. Onshore winds push seawater towards the coast. NOAA explains that the factors that affect storm surge magnitude are storm intensity, forward speed, the size of a hurricane and the angle of approach to the coast.
One of the highest storm surge events recorded in the U.S. in recent history was Hurricane Katrina in 2005. Katrina made landfall as a Category 3 hurricane along the Louisiana and Mississippi coast. According to the National Hurricane Center, Hurricane Katrina generated a storm surge of 24 to 28 feet along the Mississippi coast. The Tropical Cyclone Report for Hurricane Katrina states that the highest watermark observation was 27.8 feet at Pass Christian east of Bay St. Louis.
As Florida braces for the impacts of Hurricane Helene, the Big Bend region of Florida is expected to have a 15- to 20-foot storm surge when Helene makes landfall. Areas as far south as Tampa could expect a storm surge of 5 to 8 feet. Fort Myers could expect to see a storm surge of 4 to 7 feet. Helene is expected to make landfall late Thursday into the early hours of Friday likely as a Category 4 hurricane.
