Extreme Weather Toolkit: Tropical Cyclones

Warming oceans fuel stronger tropical cyclones that bring more heavy rainfall and higher storm surge when they make landfall.

Tropical cyclones, which include hurricanes and tropical storms, can generate multiple devastating hazards, including storm surge, flooding, winds of 100 mph or more, and tornadoes. 

People living near coasts are especially vulnerable to these tropical cyclone hazards and the risks of injury, death, and property damage. 

Tropical cyclones are the costliest type of weather disasters in the U.S by far. They account for over half of the total cost of all billion-dollar disasters since 1980. 

Nine of the 10 most costly weather disasters since 1980 in the U.S. were hurricanes. The top three (Hurricanes Katrina, Harvey, and Ian) caused an estimated total of $484 billion in damages. 

Warming of the surface ocean due to human-caused climate change is causing more tropical cyclones to reach the most severe categories. Globally, human-caused warming has increased the likelihood of a hurricane developing into a Category 3 or stronger by about 5% per decade since 1979. The latest IPCC report concludes that the proportion of very intense (Category 4 and 5) tropical cyclones is projected to increase globally with continued global warming. 

Climate change increased maximum wind speeds for every Atlantic hurricane in 2024, according to a Climate Central analysis based on new peer-reviewed research, and is increasing the fraction of storms that undergo rapid intensification. 

Although the frequency of tropical storms is not necessarily increasing, sea level rise can amplify potential storm surge when storms do occur, putting coastal residents at particular risk. 

Tropical cyclone rainfall rates are increasing by more than 1% per year, with further increases expected with further warming. This higher rainfall intensity, combined with the fact that climate change is enabling tropical cyclones to maintain more of their strength after making landfall, increases the risk of inland flooding, which accounts for more than half of past U.S. hurricane fatalities.

Updated: May 2025