Official hurricane season could start sooner
By Matthew Cappucci
February 26, 2021 Tropical Storm Arthur during May 2020.
The Atlantic hurricane season doesn’t officially start until June 1, but that could soon change. A committee at the National Hurricane Center in Miami, part of the National Oceanic and Atmospheric Administration, is working to decide whether the start date of Atlantic hurricane season should be moved forward to May 15.
The change would reflect an increasing tendency for early-season storms to form ahead of the internationally agreed-upon June 1 conventional start date.
The National Hurricane Center has already announced plans to begin issuing routine tropical weather outlooks starting on May 15.
The 2020 Atlantic hurricane season sparked to life early last year when Tropical Storm Arthur formed east of Florida on May 16. It produced sustained winds of 39 mph on the Outer Banks of North Carolina. Before its formation, the waterlogged disturbance interacted with another atmospheric wave to drop 10 inches of rain on Marathon, 8 inches on Fort Lauderdale and 6 on Miami.
It was the sixth consecutive season to feature a preseason storm before the official June 1 start date. Tropical Storm Alberto in late May 2018 brought nearly a foot of rainfall near Lake Okeechobee, while also producing 65 mph winds over the Gulf of Mexico. A storm surge of roughly 3 feet was observed in the Florida Panhandle.
In 2015, Tropical Storm Ana scraped the East Coast in mid-May.
Also forming early in the past six seasons were a number of subtropical storms — hybrid systems that bear the characteristics of ordinary mid-latitude and tropical cyclones — which began receiving names in 2002.
Since 2000, 11 storms have been named before the official start of hurricane season.
“Many of the May systems are short-lived, hybrid (subtropical) systems that are now being identified because of better monitoring and policy changes that now name subtropical storms,” wrote Dennis Feltgen, a meteorologist and public affairs specialist at the National Hurricane Center, in an email. “In 2020, NHC issued 36 ‘special’ Tropical Weather Outlooks prior to June 1st.”
These unscheduled outlooks, which aren’t otherwise issued until June 1, were issued in response to Arthur and Bertha.
In its annual hurricane plan, the World Meteorological Organization announced the National Hurricane Center “will determine a quantitative threshold for adding or removing dates from the official Atlantic Hurricane Season,” and “will then examine the need for ... potentially moving the beginning of hurricane season to May 15.”
Research supports that warming Atlantic waters in response to the changing climate could become supportive of tropical storms and hurricanes earlier in the season than in years past, making the issue more topical.
The average date of a season’s first named storm has shifted upward by about a month since 1970. At first glance, it would be easy to attribute that to climate change — but better technology and satellites in today’s day and age mean meteorologists are able to track and name storms that otherwise may have been missed. Subsequently, the shifting date is likely a product of both better detection and warming oceans.
The preseason storm activity “seems to be, certainly, very attached to sea surface temperature,” Jim Kossin, an atmospheric scientist with the National Oceanic and Atmospheric Administration, said in July. “There’s no question about that.”
There have been calls for years to revise the official start date of Atlantic hurricane season to May 15, matching the first day of hurricane season in the east Pacific. June 1 is an arbitrarily chosen date; some think it’s time to change the definition to reflect reality.
Others, including former Federal Emergency Management Agency director W. Craig Fugate, have expressed little interest in the semantics of when hurricane season starts, noting that a changed date would do little to spur public preparation.
Despite the habitual messaging of both FEMA and the National Hurricane Center urging a state of vigilance throughout hurricane season, each landfalling storm still brings about a mad dash for food, water and supplies — making some question whether the advertised start date of a season has any real-world significance.
As it stands, fewer than 100 days remain until the official start of hurricane season this year, and after a record 30 named storms in 2020, this season could once again be active. A La Niña weather pattern, coupled with myriad other atmospheric factors, could load the dice toward another challenging season. https://www.washingtonpost.com/weather/2021/02/26/hurricane-season-lengthening-start-date/