Many storms were missed over the open ocean prior to hurricane hunter aircraft in 1944. Even then half of the Atlantic basin was not covered. Satellite coverage began to improve matters in 1966. But even then monitoring has considerably improved since 1966, particularly regarding short lived storms.
Contrary to popular myth, the year with most major hurricanes was not 2005, but 1950, when there were eight.
To have four, as we have so far had this year, is not in the slightest unusual. In fact, there have been 27 years on the record, when there has been four or more major hurricanes.
But are hurricanes getting more powerful?
Well, not according to the ACE index (1), which shows hurricane seasons in the past every bit as strong as the past couple of decades.