Hurricane Helene recently made landfall on Florida’s Gulf Coast as a category 4 storm with 140 mile per hour winds and storm surge up to 15 feet. Damages left in the storm’s wake have been devastating. Now, Hurricane Milton, which has strengthened to a category 5 storm, is on a path to the same region in Florida about two weeks later. Research shows scenarios like this are becoming more likely and will continue to do so in the future.

A study published last year in the journal Nature Climate Change examined how frequent back-to-back damaging hurricanes and tropical storms have been historically along the U.S. East and Gulf coasts, as well as what projections show that frequency may be by the end of the century. Research has shown that tropical storms are intensifying, owing in part to warmer waters that feed hurricanes, but the scientists behind this study focused on damaging sequential hurricanes that hit the same area in quick succession.

Ning Lin, lead researcher and associate professor of civil and environmental engineering at Princeton, says, “Sequential hurricane hazards are happening already, so we felt they should be studied. There has been an increasing trend in recent decades.”

Using computer simulations, and considering moderate carbon emission and high carbon emission scenarios, the team found that the chance of back-to-back damaging storms has been going up in coastal areas in recent decades on the East and Gulf coasts, though they’re still rare at the moment. However, both emission scenarios call for them to continue to become more likely in the future. In fact, their findings suggest that areas like the Gulf Coast could face such scenarios as often as once every three years.

The models in this study showed an increase in overall storms, as well, which hasn’t necessarily been seen in other studies. However, researchers say the increase in sequential damaging storms is still there, even if there aren’t more overall storms, due to the trend toward higher intensity hurricanes driven by higher temperatures and sea level rise. These conditions lead to increased rainfall and more damaging storm surge, which can cause even more devastating flooding.

The researchers say their study should encourage city planners and first responders to prepare for a future with more back-to-back hurricane damage. This should be considered in resilience strategies, coastal infrastructure, and emergency services, with a special focus on essential services like transportation, water systems, and power grids.

Lin says, “If a power system requires 15 days to recover from a major hurricane, we cannot wait that long in the future because the next storm can hit before you can restore power, as in the case of Nicholas following Ida. We need to think about plans, rescue workers, resources. How will we plan for this?”

If you’d like to help those impacted by the back-to-back hits of Helene and Milton, click here.