SAVANNAH, Ga (WSAV) — Over the past several decades, tropical systems have been frequently and rapidly intensifying as they develop, often just as they are about to make landfall.
In 2021, Elsa, Grace, Ida, Larry, and Sam rapidly intensified in the Atlantic basin.
Rapid intensification is when the sustained wind of a storm increases at least 35 mph within 24 hours.
Hurricane Ida formed in the Caribbean Sea, eventually achieving category 2 status in late August in the Gulf of Mexico.
Within a span of two days, Ida rapidly intensified to a category 4 hurricane with 150 mph wind.
Ida went on to make landfall as a category 4 hurricane with peak winds of 150 mph in southeast Louisiana.
Climate change and multidecadal weather patterns have been favorable for more storms to develop and for hurricanes to become larger, stronger, and longer-lasting. Larger storms produce greater storm surge and more inland flooding because of heavier rainfall amounts.
One of the main ingredients needed for tropical development is warm ocean water temperatures of 80°F or greater.
Since 1880, almost as far back as water temperature records go, the average global water temperature has increased about 2 tenths of a °F per decade. Most of the warming has occurred in the last 30 years.
In the Gulf, water temperatures on average run 1-2°F warmer than normal with near-shore water often over 90°F in the summer. Off of the east coast, the Gulf Stream is normally warmer than 80°F and at times it is more than 82°F. That is enough to enhance further development of tropical storms and hurricanes as they approach the coast.
Situations like hurricane Ida in 2021 show us that we should always prepare for a hurricane that is at least one category stronger than what is forecast.