What the Busiest Atlantic Hurricane Seasons Have Delivered in October

 Jonathan Erdman

Published: September 30, 2020

The 2020 Atlantic hurricane season is on a record pace for named storms through September and if the busiest hurricane seasons in history are a guide, October could once again see a flurry of storms and hurricanes.

With officially two months of the hurricane season left, we've already blown through 23 storms, second-most of any hurricane season behind only 2005's 28.

For only the second time, the Greek alphabet is in use for additional storms, after Tropical Storm Wilfred exhausted the season's list of names on Sept. 18.

(MORE: Records the 2020 Atlantic Hurricane Season Has Broken So Far)

October isn't the peak of the hurricane season, but from 1950 through 2019, an average of about two named storms form each October, one of which becomes a hurricane. Every other October, on average, one of those hurricanes intensifies into a major hurricane, at least Category 3 intensity.

What can we expect this October?

To shed some light on this, we examined the busiest hurricane seasons of the past to see what could happen this year. We looked at the seasons with both the most storms and most hurricanes.

For brevity, we omitted consideration of a metric called the ACE index – which takes into account not just the number, but also the intensity and longevity of storms and hurricanes – since this season's ACE index isn't as anomalous relative to other seasons as the number of storms and hurricanes.

October in Seasons With Most Storms

Prior to 2020, the seasons with the most Atlantic storms after 2005's 28 storms were 1933 (20), and five seasons each with 19 – 1887, 1995, 2010, 2011 and 2012.

In October, those seven seasons produced an average of four to five named storms, and two to three became hurricanes.

October named storms in those seven busy seasons ranged from one in 2011 to seven in 2005.

October storms, hurricanes and Category 3 or stronger hurricanes in the seasons with the most storms on record, denoted by the yellow bars, compared to the long-term October average, shown by the blue bars. (Note: More than five seasons with most storms were considered, due to ties in named storms in 1887, 1995, 2010, 2011 and 2012.)

October in Seasons With Most Hurricanes

Through the end of September, we've already chalked up eight hurricanes in the 2020 season.

Prior to 2020, the seasons with the most Atlantic hurricanes after 2005's 15 were 1969 and 2010 – 12 hurricanes each – and four seasons with 11 each – 1887, 1933, 1950 and 1995.

In October, those seven seasons produced an average of five to six named storms, three to four of which became hurricanes.

October hurricanes in those seven busy seasons ranged from two in 1933 and 1995 to five in 2010.

October storms, hurricanes and Category 3 or stronger hurricanes in the seasons with the most hurricanes on record, denoted by the red bars, compared to the long-term October average, shown by the blue bars. (Note: More than five seasons with most hurricanes were considered, due to ties in named storms in 1933, 1887, 1995 and 1950.)

October Takeaways

If those past record-busy hurricane seasons are any indication, we could see anywhere from two to four more October storms than average and one to three more October hurricanes than average this season.

That could be a significant concern because the typical October breeding grounds and tracks for storms are closer to land, from the western Caribbean Sea to the eastern Gulf of Mexico, Florida and the East Coast.

Among the notable October hurricanes in those busiest seasons were hurricanes Wilma and King, which hammered South Florida in 2005 and 1950, respectively.

Infrared satellite image of Hurricane Wilma as it made landfall in South Florida on Oct. 24, 2005, at Category 3 intensity.

Later in the record 2005 season, Hurricane Beta soaked Nicaragua and Honduras with flooding rain and storm surge.

In 2010, another of the busiest hurricane seasons for both storms (19) and hurricanes (12), Hurricane Tomas slammed into the Windward Islands at Category 2 intensity the day before Halloween.

As you often hear with investments, past performance is no guarantee of future results. But if this busy season holds serve with the others, we still have a long way to go before closing the books on the 2020 Atlantic hurricane season.

The Weather Company’s primary journalistic mission is to report on breaking weather news, the environment and the importance of science to our lives. This story does not necessarily represent the position of our parent company, IBM.

The Weather Company’s primary journalistic mission is to report on breaking weather news, the environment and the importance of science to our lives. This story does not necessarily represent the position of our parent company, IBM.