The US just raised its hurricane season averages after a decade of higher storm activity

There’s a new normal for the Atlantic hurricane season.

Increased storm activity over the past decade means the National Oceanic and Atmospheric Administration had to raise the number of named storms it considers to be “average” — from 12 to 14.

Every 10 years, NOAA adjusts its annual average to reflect storms over the previous 30 years.

“The reality check is here,” said AccuWeather meteorologist Dan Kottlowski. “Since 1995 there’s been a steady climb in numbers.”

The new average is now calculated using the 1991-2020 seasons. While the average number of total storms increased by two, the number of hurricanes was reduced from seven to six and major hurricanes — categories 3 or higher — remained unchanged at three.

Previously, NOAA used 19812010 as its 30-year period to declare a season as above, near or below average.

“This update allows our meteorologists to make forecasts for the hurricane season with the most relevant climate statistics taken into consideration,” said Michael Farrar, director of NOAA’s National Centers for Environmental Prediction in a statement. “Our work illustrates the value of NOAA’s investments in next-generation technologies to capture the data that underpins our outlooks and other forecast products.”

The increase in storms could be due to climate change, which warms the atmosphere and ocean water, NOAA said, but it also could be due to better observational equipment.

NOAA is scheduled to issue its 2021 hurricane season outlook in late May.

Colorado State issued its 2021 hurricane season prediction Thursday, projecting 17 named storms, eight hurricanes and four major hurricanes — above average by both the old and new calculations.

AccuWeather’s seasonal forecast also projected above-average activity with 16 to 20 named storms, seven to 10 hurricanes, and three to five major hurricanes. The 2020 hurricane season was the busiest in recorded history with 30 named storms, 13 hurricanes — 12 of which made landfall in the continental U.S. — and six major hurricanes.

Among the reasons for the above-average 2021 storm predictions, according to Kottlowski and others, are the storm-sheering winds of an El Niño weather pattern and warmer-than-normal water in the subtropical Atlantic.

Kottlowski said about 30 years ago an average hurricane season was 10 named storms, five hurricanes and two major hurricanes.

“People need to think, ‘OK, the averages have gone up,’ “he said. “That means you’ve got to expect more storms regardless of what you hear about how many storms there are going to be.”

COURTESY The 2020 hurricane season was the busiest in recorded history.