Times are changing at the National Oceanic and Atmospheric Administration (NOAA); beginning with this year’s hurricane season outlooks, the Climate Prediction Center (CPC) will use 1991-2020 as the new 30-year period of record. By using this new period to create what is an “average” season, the number of Atlantic storms has increased. NOAA evaluates what’s average every 10 years, updating its set of statistics to help determine whether or not a season is above, near, or below what is average when compared to the climate record.
With these changes, the number of named storms in an average year is now 14, with 7 hurricanes. According to NOAA, the average for major hurricanes (Category 3, 4 or 5) remains unchanged at 3. The previous Atlantic storm averages, based on the period from 1981 to 2010, were 12 named storms, 6 hurricanes, and 3 major hurricanes.
“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. “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. These products are essential to providing the public and local emergency managers with advance information to prepare for storms, and achieving NOAA’s mission of protecting life and property.”
“These updated averages better reflect our collective experience of the past 10 years, which included some very active hurricane seasons,” said Matt Rosencrans, seasonal hurricane forecaster at NOAA’s Climate Prediction Center. “NOAA scientists have evaluated the impacts of climate change on tropical cyclones and determined that it can influence storm intensity. Further research is needed to better understand and attribute the impacts of anthropogenic forcings and natural variability on tropical storm activity.”
While the averages for the Atlantic hurricane basin are changing, the averages used for the Eastern Pacific and Central Pacific basins is remaining the same. The Eastern Pacific basin will remain at 15 named storms, 8 hurricanes, and 4 major hurricanes while the Central Pacific basin, which surrounds Hawaii and nearby waters, will maintain an average of 4 named storms, 3 hurricanes and 2 major hurricanes.
Just yesterday, experts unveiled a seasonal outlook that shows the 2021 Atlantic Hurricane Season being a busy one. Meteorologists with the Colorado State University’s Tropical Meteorology Product, led by Dr. Phil Klotzbach, unveiled their outlook at the National Tropical Weather Conference yesterday, projecting that an above-normal 2021 hurricane season will produce 17 named storms in the Atlantic. Of those 17 storms, they believe 8 will become hurricanes and 4 will become major hurricanes.