Hurricane Irma on Sept. 5, 2017. (NOAA/NASA/CIMSS)

We’re only halfway through hurricane season, but already we’ve had enough — enough destruction, enough storms, enough tropical activity in the Atlantic Ocean to fill an entire year.

So far this season, the Atlantic has produced:

  • 11 named storms (Arlene to Katia)
  • Six hurricanes (Franklin, Gert, Harvey, Irma, Jose, Katia)
  • Three major hurricanes, Category 3-plus (Harvey, Irma, Jose)
  • Two major hurricane landfalls on U.S. mainland (Harvey, Irma)

We could expect to see as much in an entire “normal” season. But this year has been anything but normal.

Of these storms, Hurricane Irma, was certainly the strongest. It stayed a Category 5 storm for three days, the longest duration since we’ve been monitoring the Atlantic via satellite since the 1960s. Harvey’s winds may not have been as strong as Irma’s, but it was record-breaking in other ways. Without strong steering currents to push it away from the Gulf of Mexico, it poured rain for several consecutive days over Southeast Texas and caused catastrophic flooding.


Another way to look at the season is in terms of accumulated cyclone energy, which takes into account the time each storm spent in the Atlantic. Using this metric, this season is already twice as active as a “normal” season, and through Sept. 14 it is already about 120 percent of what we’d usually see at the end of a typical year.


Total accumulated cyclone energy through Sept. 15, compared to average. (atmos.colostate.edu)

Now we’re watching Hurricane Jose, along with two other areas of interest behind it, including a newly designated tropical depression. The forecast for Jose remain uncertain, but even if the storm doesn’t make landfall in the continental United States, its effects may spread over the East Coast next week. At the very least, the storm will continue to contribute to an increasingly active Atlantic hurricane season.