Records
Most active hurricane season ever: 2005 vs 2020
The Atlantic has two champions. One season carried the most energy, and another used up so many names that it reached the Greek alphabet. The Pacific is busier than both.
Most energy (Atlantic): 2005, with an accumulated cyclone energy (ACE) of 245.3 on our season page, the highest Atlantic total in the archive.
Most named storms (Atlantic): 2020, with 30 named storms, the most in any Atlantic season on record.
2005: the most energy
ACE adds up each storm's squared one-minute wind at six-hourly times while it is at tropical storm strength or above, so long and strong storms score highest. The 2005 season produced 31 storm records in the archive, 28 that reached tropical storm strength, 15 hurricanes and 7 major hurricanes. The next highest Atlantic totals are 1995 at 227.4 and 2004 at 226.9. The 2005 season page has the tracks behind the figure.
2020: the most names
The 2020 season produced 30 tropical storms in the archive, matching the 30 named storms in the season summary. It ran through the full list of names and into the Greek alphabet, so it is the busiest Atlantic season by storm count. The 2020 season page lists them.
The Pacific is busier
The western Pacific holds the busiest seasons in the archive. The 1964 season had 38 storms at tropical storm strength, and 1967 had 52 storm records of any strength. Its highest ACE is 2004 at 477.3. The eastern Pacific's highest is 1992 at 447.2, with 31 storms reaching tropical storm strength.
What the rankings leave out
The archive starts in 1950. The 1933 Atlantic season ranks above 2005 on ACE in published reconstructions that use data from before the archive. ACE values also depend on method: the 245.3 on our season page matches the figure in Wikipedia's 2005 season article.