An average season produces 12 named storms, 6.5 hurricanes, and 2 major hurricanes.
“This is our lowest-ever forecast issued in April,” Klotzbach said.
Klotzbach, who is a research scientist at Colorado State University, has worked since 2000 with Bill Gray, who began making and publicizing seasonal hurricane forecasts in the 1980s.
Klotzbach said several factors have lined up that are hostile to Atlantic hurricane activity. An El Niño event, which generates upper level winds that disrupt storm formation, has developed and is forecast to strengthen by the fall – possibly to moderate-to-strong levels.
He also said sea surface temperatures, which help fuel developing storms when they’re warm, are substantially cooler than normal in the tropical Atlantic.
“[The environment] is pretty much the opposite you’d want to see if you were looking for an active season,” Klotzbach said.
Concerns about complacency
Klotzbach and other hurricane forecasters stress a forecast for an inactive season does not reduce the need for preparedness. In the “inactive” 1992, which produced just 7 named storms, Hurricane Andrew devastated South Florida. There were only 4 named storms in 1983, but Hurricane Alicia struck Galveston and Houston, becoming the costliest storm since Agnes.
“This forecast doesn’t mean we won’t have any impacts,” Klotzbach warned.
“It doesn’t matter what the numbers are in terms of what the public needs to do to prepare,” added Rick Knabb, director of the National Hurricane Center.
There is concern the forecast for a quiet season combined with a lack of hurricane landfalls in the U.S. in recent years is lulling coastal residents into a false sense of security.
A major hurricane has not struck the U.S. coast since Wilma in 2005, almost 10 years – the longest period on record (the previous record spanned the Civil War from 1861-1868). This is despite some active hurricane seasons in this span.
“We’ve been pretty lucky,” Klotzbach said, noting low pressure off the East Coast has shielded it from landfalls.
Klotzbach noted there have been 40 percent fewer major hurricane landfalls in the last 50 years compared to the previous 50 years.
Klotzbach and Gray’s seasonal hurricane forecasts, while far from perfect, have provided a reasonably good sense of how activity will compare to normal over time. In the last 16 years, dating back to the 1999 hurricane season, the duo has correctly indicated whether activity will be above or below normal 13 times.
“In general, our forecasts are successful at forecasting whether the season will be more or less active than the average season by as early as April,” Klotzbach and Gray wrote in a self-assessment. “We tend to have improving skill as we get closer in time to the start of the hurricane season.”
The outlook issued ahead of last year’s hurricane season – which called for slightly below average activity – was considered quite successful. It called for 9 named storms and 3 hurricanes and there were 8 named storms and 6 hurricanes.
Klotzbach’s prediction echoes those made by others issued, thus far.
The private forecasting group WeatherBell is predicting 7-9 named storms, 3-5 hurricanes, and 1-2 major hurricanes.
Chris Hebert, a forecaster with ImpactWeather – a weather consulting firm, is calling for 8 named storms, 4 hurricanes and 2 major hurricanes. In addition to the cool ocean temperatures in the Atlantic, Hebert said there’s a great deal of hostile dry air in parts of the storm development region, “even more so than last year,” he said.
NOAA typically issues its seasonal forecast outlook in May.