But is it global warming? What is the evidence that the growing concentrations of carbon dioxide and other greenhouse gases in the atmosphere are changing weather systems in such a way that hurricanes become more powerful, or more frequent?” (BBC)
There have been 270% the average number of intense storms expected by this date in the hurricane season, but it is certainly rash to draw conclusions from a given year. The formation of tropical storms over the Atlantic runs in phases, and we are in the midst of a several-decade active phase. However, we are almost certainly seeing an effect, from the warming of the average surface water temperature in the Gulf of Mexico, on the storms that cross the Gulf.