Hurricane Season: NOAA updates 30-year reference period

The National Oceanic and Atmospheric Administration (NOAA) updated its 30-year climatological average in 2021. If you see different numbers in the average storms this season, know that these numbers have been updated to reflect the most recent 30 years.

Instead of using data from the 1981-2010 average, NOAA began comparing hurricane activity in relation to the 1991-2020 30-year average. This update reflects the overall improvement in observing platforms, satellites and hurricane reconnaissance tools. Averages are updated every ten years. This means when we come to 2031, NOAA will look at the 2001-2030 climate averages.

But what does this have to do with hurricane season? According to NOAA, using the new 1991-2020 30-year average, the average number of named storms each season in the Atlantic basin has increased to 14 named storms. This is up from 12 from the 1981-2010 average.

Eight of the 14 named storms are likely to become hurricanes while three could become major hurricanes, reaching at least a category three status. During the 1981-2010 period, six of the 12 named storms were estimated to be hurricanes with three becoming major hurricanes.

The 30-year average period was also updated in the Pacific Basin, although the results stayed the same.

For the Eastern Pacific, the 30-year average shows 15 named storms, eight hurricanes, and four major hurricanes, while in the Central Pacific, there were four named storms, three hurricanes and two major hurricanes for the 1991-2020 period.

This 2025 Atlantic Hurricane Season looks to be more active than average. Warmer-than-average sea surface temperatures and a neutral ENSO could make this year active. Our team of experts will keep a close eye on any storms brewing that might threaten land.