A recent article in Geophysical Research Letters indicates that the most powerful hurricanes are strengthening more quickly than they used to, according to a newsletter from the Pacific Northwest National Laboratory. While hurricanes as a whole are not rapidly intensifying more often than in the past, the most powerful storms are getting stronger more quickly than in previous decades. Hurricanes strengthen for a number of reasons that are related to sea surface temperatures and vertical wind profiles, so it is likely that these factors are also changing over time. You can read more at https://www.pnnl.gov/news/release.aspx?id=4504.