The Atlantic is in for another “above-normal” hurricane season this year, though not to the historic storm levels of 2020, the National Oceanic and Atmospheric Association (NOAA) has warned.
NOAA’s Climate Prediction Center says there’s a 60 percent chance the 2021 Atlantic hurricane season – which lasts from June 1 to November 30 – will be above-normal, with a predicted 13 to 20 named storms, six to 10 of which could become hurricanes with winds of up to 119 kilometers per hour (74 miles per hour) and up to five that could develop into major hurricanes, with winds of 179 kph (111 mph).
Last year’s record-breaking season saw 30 “named” storms – storms that reach tropical or higher strength – with meteorologists exhausting the Latin 26-letter alphabet and spilling over into the Greek alphabet for only the second time ever. Thirteen of those storms were hurricanes, which is more than double the previous long-term seasonal average of 12 named storms and six hurricanes.
The season is usually at its most active in August to October, but last year saw two tropical storms (Arthur and Bertha) form in May, the sixth year running that a named storm has formed before the official hurricane season has started. Two major hurricanes, Eta and Iota, formed at the very end of the season in November, with Iota reaching category 5, with winds of 260 kph (162 mph), causing severe devastation in Central America upon landfall.
This "new normal" has meant that the Climate Prediction Center is forgoing the previous long-term storm season model based on data from 1981 to 2010 and introducing a new 30-year dataset model from 1991 to 2020 to better reflect the increasingly active Atlantic hurricane season. Better technology and understanding of how storms form and move has also meant that NOAA has recalibrated what an "average" hurricane season looks like, updating its statistics to 14 named storms and seven hurricanes for an average season. Despite the fluctuating timescale of the season, the official start date remains June 1.
The European Organisation for the Exploitation of Meteorological Satellites' just-released annual Year of Weather video shows 2020's particularly wild weather from a satellite perspective. Combining data from its own satellites with that of NOAA and the Chinese and Japanese meteorological agencies, it highlights in stark visuals how active last year's Atlantic hurricane season was. The named storms are tagged in color ranging from yellow to red depending on intensity.
The World Meteorological Organization has released the proposed names for 2021's storm season while retiring four previous names – including Eta and Iota – due to the death and destruction they caused. It has also said it will not be using the Greek alphabet in the future as it felt it distracted too much from the impact of the storms.
The names on the list so far include Ana, Bill, Claudette, Danny, Elsa, Fred, and Grace right through to Wanda, where it will presumably start again if the number of named storms exceeds 26 in the coming season.
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