The 2020 Atlantic hurricane season came to an end Monday after shattering records and causing devastation across North America.
There were a record 30 named storms, 12 of which made landfall, surpassing the record of 28 named storms in 2005, according to the National Oceanic and Atmospheric Administration, or NOAA. Thirteen of the storms became hurricanes, the second-highest number on record, behind only the 15 in 2005.
"In some ways it was astounding, and it's amazing to see what nature can do," said Matthew Rosencrans, climate testbed director at NOAA's Climate Prediction Center.
Rosencrans said an interconnected set of oceanic and atmospheric conditions that meteorologists use to make predictions all pointed toward a busy season back in May.
"It's been a record-breaking year, which has kept NOAA and the National Weather Service quite busy throughout the entire Atlantic hurricane season providing all the watches and warnings and information we needed to," he said.
An average Atlantic hurricane season — which begins June 1 and ends Nov. 30 — has 12 named storms, six hurricanes and three major hurricanes. This season, by comparison, brought at least double all of those: 30 named storms, 13 hurricanes and six major hurricanes. The number of major hurricanes nearly matched the record of seven set during the 2005 season, according to NOAA.
"The 2020 Atlantic hurricane season ramped up quickly and broke records across the board," acting NOAA Administrator Neil Jacobs said in a summary released last week.
The first two named storms arrived in May, before the season's official start. By the end of July, there had been a record nine named storms. There were so many that the 21-name list of Atlantic tropical cyclones was exhausted with Tropical Storm Wilfred on Sept. 18, with more than two months left in the season.
"For only the second time in history, the Greek alphabet was used for the remainder of the season, extending through the 9th name in the list, Iota," NOAA said in its summary.
The season was not just productive. It was also destructive.
Kerry Emanuel, a professor of atmospheric sciences at the Massachusetts Institute of Technology, said two sets of hurricanes struck at nearly the same places this season, to devastating results.
Category 4 Hurricane Laura and Category 2 Delta struck about 15 miles from each other just six weeks apart in southwest Louisiana in August and October, leaving the community reeling.
Hurricane Laura, which struck on Aug. 27, was one of the strongest storms to make landfall in the United States, with sustained winds of 150 mph.
Later in the season, Hurricane Iota churned toward Nicaragua as a powerful Category 5 storm before reaching land as a Category 4 on Nov. 16 with maximum sustained winds near 155 mph. The storm wreaked havoc at nearly the same location that Category 4 Hurricane Eta had hit two weeks earlier.
The storms caused flooding and mudslides that forced thousands of people to evacuate.
Emanuel said storms could bring more damage in the future as temperatures get warmer around the globe and storms cause more rain, "and that's really important, because far and away water is a big killer in hurricanes."
"We're beginning to see that in the data that storms are raining more," he said.
He also said that because storms were more intense and because sea levels were higher, experts expect the problem to worsen with storm surges.
Asked whether there could be more record hurricane seasons, he said: "We're certainly going to have ups and downs. We're going to have quiet seasons and busy seasons, there's no doubt about that.
"The one thing I think we're confident of is we're going to, in general, start seeing more intense storms unless we do something about the greenhouse gases and we're going to see wetter and wetter storms causing more flood problems," he said.
Rosencrans said the Atlantic season has been "anomalous" in that it has produced major hurricanes, such as Eta and Iota, through November, when storms usually are fewer and less severe.
He warned people to take hurricane season seriously from beginning to end and to know that a season can extend beyond an official end date.
"We saw it start in May and go all the way into November," he said. "So just getting prepared early and being prepared for the entire season. We really saw a full season this year. It's really important for people to understand."