Hurricane Humberto strengthened from a tropical storm into a hurricane at 5am on Wednesday morning. If it would have taken just three more hours, it would have gone down in history as the latest "first" hurricane in several decades.
Usually by September 4th there has already been a major hurricane in the Atlantic. This year, the Atlantic has held off in producing even a weak-grade hurricane till September 11th.
There are two main reasons storm strength is down. The first is an excess of dry air and dust coming off of Africa. This dry air strangles the storms and keeps them from intensifying. The second thing that has been keeping the storms in check is the windy conditions over the water. These environmental winds tear apart storms before they can organize into that tell-tale swirl. Wind and dry air have been so effective at keeping storm threat down that a record was almost set this morning.
Barry, Chantal, Dorian, each storm flared up before dying because of winds or dry air tearing the storms apart. None of these storms made it to hurricane strength, which is rare according to the National Hurricane Center. Usually the Atlantic spins out its first hurricane by August 10th.
Aside from this year only three other years have not had a named hurricane by the end of August: 1984, 2001, and 2002.