The Intensification Rate for Tropical Cyclones to Reach Category 1 and Above Intensity

Abstract While rapid intensification (RI, ≥30 kt/24hr) is known to be crucial for major hurricanes, the broader role of maximum intensification rate in shaping tropical cyclone (TC) lifetime maximum intensity (LMI) is less understood. Using global best‐track data from 1982 to 2023, we show that experiencing an intensification rate of 20–25 kt/24hr, defined as critical intensification (CI), is a fundamental prerequisite for reaching Category 1 or higher intensity (LMI ≥ 64 kt). storms achieving Category 1 or higher undergo CI. CI in early development stage initiates structural changes, such as contraction of the radius of maximum wind (RMW) and increase of intensity, that create favorable conditions for subsequent RI. of RI storms first experience CI, highlighting its precursor role. These findings identify CI as an important threshold shaping storm intensity pathways and provide new insight into the distribution of TC LMI.