Adaptive mobility responses during Hurricanes Helene and Milton in 2024.

Adaptation is crucial for minimizing the societal impacts of tropical cyclones amid climate change. Using 3.56 billion high-resolution foot-traffic records from mobile devices, we analyzed human mobility patterns during Hurricanes Helene and Milton, which struck the southeastern United States in 2024. We observed marked differences in adaptive mobility responses across geographic regions with varying levels of historical hurricane exposure. Milton primarily impacted coastal areas with frequent hurricane exposure and prompted sharp increases in out-region travel prior to landfall and sustained elevated mobility in the post-disaster period. In contrast, Helene affected mostly inland areas, where mobility changes were modest and largely within natural variation. Within Helene-affected regions, coastal counties showed stronger mobility responses than inland counties. Our findings underscore the need for tailoring disaster preparedness and response strategies to the specific characteristics of affected populations.