Scientists at Climate Forecast Applications Network (CFAN) have forecast an 80% probability of an above normal 2018 Atlantic hurricane season after claiming to have made a breakthrough in understanding the long-range impact of global climate dynamics on Atlantic hurricane activity.
Their new model predicts a total Accumulated Cyclone Energy (ACE) of 132 (+/-50) and 1.7 (+/-1.1) U.S. landfalls for 2018 – values that are near the averages for the active period since 1995.
Judith Curry, President of CFAN, said; “forecasts in December for next year’s Atlantic hurricane activity help many businesses. For example, they provide valuable guidance to those writing or using insurance and reinsurance contracts.”
However, many experts believe forecasts for hurricane activity made before June are too early to place much emphasis on.
CFAN said its predictions are based on sea surface temperatures patterns in the tropical Pacific – responsible for El Nino and La Nina events – and the North Atlantic.
James Johnstone, senior scientist at CFAN, explained that; “backtesting of CFAN’s forecast model shows moderate predictive skill of U.S. landfall totals and North Atlantic ACE two years later.
“It accurately indicates high levels of activity for the years of 1995, 2004, 2005, 2011, and 2017. It accurately indicates low levels of activity during the multiyear hurricane ‘droughts’ of 2000-2002 and 2013-15.
“The model captures low-frequency aspects of interannual hurricane variability, forecasting periods of active and inactive years, but typically underestimates the amplitudes of specific annual anomalies.”
CFAN’s scientists said they’ve found precursors to seasonal Atlantic hurricane activity with lead times as far as 1-2 years – based on systematic, repeating interactions among tropical Pacific sea surface patterns, atmospheric circulation patterns over the tropical North Atlantic and the Caribbean Sea, and stratospheric circulation patterns.
Tropical Storm Risk’s Extended Range Forecast for 2018 Atlantic Hurricanes has also predicted that “Atlantic hurricane activity in 2018 will be slightly above the long-term norm and close to the last 10-year norm.”
However, the forecaster added that “the uncertainties associated with this outlook are large and the forecast skill at this extended range is historically low.”
