HOUSTON – Phil Klotzbach, a researcher and hurricane expert at Colorado State University, has issued his July updated forecast for the 2021 Atlantic hurricane season Thursday. He’s predicting another busy season.
Klotzbach is estimating 20 named storms, nine hurricanes and four major hurricanes to develop in 2021.
In an average hurricane season (based on 30 years of data from 1991 and 2020) there would be 14 named storms, seven hurricanes and four major hurricanes. This “new” average is above the “old” average, which was based on 30 years of data from 1981 to 2010.
In 2020, our most active hurricane season on record, 30 named storms developed, of which 13 became hurricanes and six became major hurricanes (Category 3 or higher).
Klotzbach bases his hurricane forecast on multiple factors, including climatology, Atlantic Ocean temperature and the ENSO (El Niño Southern Oscillation) cycle.
Klotzback thinks the tropical Atlantic Ocean will be warmer than normal headed into hurricane season, which officially begins June 1 and runs through Nov. 30. Warmer ocean water provides more energy for hurricanes to flourish.
Regarding the ENSO cycle, we are currently experiencing a La Niña, which is cooler-than-normal water in the equatorial Pacific off the coast of South America. A La Niña causes wind patterns in the atmosphere that promote hurricane development. Thankfully, the current La Niña is diminishing and we should head into hurricane season with an ENSO-neutral (neither El Niño or La Niña) scenario by the time hurricane season begins. El Niño patterns tend to diminish hurricane formation by causing hostile wind shear over the Atlantic ocean. Therefore, with ENSO-neutral conditions expected, the ENSO cycle is expected to neither promote or inhibit hurricane formation.