AIR: Average Atlantic Hurricane Season Expected

June 29, 2016

An average hurricane season is expected this year, according to AIR Principal Scientist, Dr. Eric Uhlhorn.

During a recent webinar, Dr. Uhlhorn offered an analysis of the various 2016 hurricane seasonal forecasts and discussed factors, such as La Niña conditions which could affect hurricane activity in the Atlantic and Pacific basins.

He began by recapping the 2015 hurricane season, which was affected by El Nino. He explained that pre-season Atlantic predictions were fairly accurate. There were 11 named storms, four hurricanes and two major hurricanes – Hurricane Joaquin and Patricia. Pacific Ocean storm activity in 2015 was greater than normal due to El Nino.

On average, 12 named storms occur per year with about three major hurricanes, Dr. Uhlhorn said.

The North Atlantic hurricane season officially runs from June 1 through November 30.
“The vast majority of storms occur during August through October and nearly all major hurricanes occur during this period,” said Uhlhorn.

As El Nino wraps up and La Nina takes shape, the Pacific Ocean’s water temperature has cooled. La Nina conditions tend to suppress Pacific Basin activity due to the cooler water, said Uhlhorn.

Other climate conditions that can affect tropical cyclone formation include:

  • Sarahan Air Layer – massive outbreaks of dust that emerge from Africa and can travel from across the Atlantic Ocean to North America.
  • Madden Guly Oscillation (MGO) waves travel east around the globe within 30-60 days.

The first seasonal hurricane forecast was created by Dr. William Gray, a former professor at Colorado State University in 1984. The forecast uses four predictors: observed sea surface temperatures in the Atlantic Ocean, observed upper level winds in the Pacific Ocean, the forecasted sea surface temperatures in Europe and observed sea level pressures in the Atlantic.

Colorado State’s prediction for 2016 are 14 named storms (average is 12), six hurricanes (average is six) and two major hurricanes (average is 3).

NOAA’s seasonal outlook, forecasted an average to a slightly above average storm season. There have already been three named storms this season: Alex, Bonnie and Colin. Even when early named storms form before the end of June it doesn’t mean a higher than average hurricane season, Dr. Uhlhorn noted.

2016 Atlantic Tropical Cyclone Names:

Alex
Bonnie
Colin
Danielle
Earl
Fiona
Gaston
Hermine
Ian
Julia
Karl
Lisa
Matthew
Nicole
Otto
Paula
Richard
Shary
Tobias
Virginie
Walter

Landfall storms depend on variable steering currents that can’t be predicted more than a week in advance, he said. The average is one to two hurricane landfalls per year.