Since the Civil War, there have only been four times when two consecutive years produced no hurricanes in the US. Two of them have been since the year 2000.
1930-1931 , 1981-1982, 2000-2001 and 2009-2010
Chronological List of All Hurricanes
NOAA would consider the lack of extreme weather to be extreme.
There certainly seems to be an extreme lack of extreme weather these days
Even with today’s increasingly hypersensitive detection devices, there are fewer US hurricanes.
The lack of hurricanes is worse than Trenberth thought so it automatically qualifies as an extreme event.