Hurricane season this year has been menacingly eventful, and it might not be over yet. In the wake of the devastation of three major hurricanes, comparisons are being drawn to Hurricane Katrina and other historical maelstroms. Exactly how do they all stack up?
The diameter of the storm, and hence its sweeping ambit of destruction, is the first metric to be taken into account. Diameter will often correlate to size of the storm (volume). The average diameter of hurricanes, including their gale force winds, is around 100 miles in diameter.
Once a storm reaches a threshold of 74 mph, it can be classified as a hurricane by the Saffir-Simpson scale. Dating back to the 1960s, the scale takes into account wind speed and storm surge (rise in tidal levels caused by the storm alone), and uses those numerics to spit out a single number. Those numbers correlate to the potential damage of the storm — one through five.
This past hurricane season has seen 13 storms. That might sound like a lot, but it's not if you take into consideration that the average number of storms for hurricane season is 12. But of the five of those storms that were major — Category Three or above, three of them made landfall on the United States.
Harvey was 280 miles in diameter, which, compared to Katrina at 400, was not paltry. It was estimated to rack up to speeds of 130 mph when hitting landfall in Texas. It was also tied for the 16th lowest landfall pressure in recorded history.
Harvey left in Houston four feet of rain, a downpour that won it the worst rainfall disaster in recorded U.S. history. The death toll topped 82. And experts belief that all the damage could rack up a bill of $100 billion or more.
Hurricane Maria is sort of a hurricane of all tricks. Not only did it have a pinhole eye, but it was, and still is flirting with something called the Fujiwhara Effect. If it fulfills this, it will do a little tango with tropical storms in the vicinity, creating an amplifying effect that could increase its destructive potential.