Klotzbach has kept up a running list of several records Irma has set, met or broken.
Here are a few highlights:
- 185 mph lifetime max winds — the strongest storm to exist in the Atlantic Ocean outside of the Caribbean and Gulf of Mexico on record. Hurricane Allen in 1980 had 190 mph winds.
- 185 mph max winds for 37 hours — the longest any cyclone around the globe has maintained that intensity on record. Typhoon Haiyan had previously held the record in the Pacific at 24 hours.
- It was the strongest storm on record to hit the Leeward Islands.
- The first Category 5 hurricane to hit the Bahamas since 1992.
- The first major hurricane to make landfall in Florida since Wilma (2005).
- It was the first Category 5 hurricane to make landfall in Cuba since 1924.
The storm's longevity is particularly striking, Klotzbach said in an interview with CNBC.
"Obviously Irma has been a pretty super-active storm, very long-lived, intense hurricane," he said. "It didn't have the strongest winds ever recorded, but it stayed very strong for a long time."
The timing of how it strengthened was also unusual.
"All of our superstorms in the Atlantic tend to get stronger in the Caribbean or the Gulf," Klotzbach said. "This one got super strong in the middle of the Atlantic."
Irma is now the second major hurricane to hit the U.S. this season, ending the longest period without a major landfall since 1850. Before Hurricane Harvey struck Texas earlier this season, the last major hurricane (by the Saffir-Simpson scale) to hit the U.S. was Wilma in 2005.
"We went from the longest streak on record of no landfalling hurricanes to two in two weeks," Klotzbach said.