What effect will a disappearing El Niño have on the 2016 Atlantic hurricane season?
Wait, you may rightly ask. Isn't the current El Niño one of the strongest on record?
Indeed it is. But, as expected, this one appears to have reached its peak in late 2015, and is expected to weaken substantially or disappear altogether by the start of the hurricane season.
El Niño likely played a significant suppressing role in the 2015 Atlantic hurricane season.
Dr. Phil Klotzbach, tropical scientist at Colorado State University, found June through October Caribbean wind shear was the highest on record dating to 1979. Klotzbach also said the magnitude of dry air over the Caribbean Sea in the peak season month of August and September also set a record.
These two factors contributed to the demise of five named storms tracking near the Caribbean Sea from mid-August through September: Hurricane Danny, Tropical Storm Erika, Hurricane Fred, Tropical Storm Grace and Tropical Storm Ida.
Despite that, Hurricane Joaquin was the first Category 4 or stronger hurricane to make an October strike on the Bahamas since 1866.
(MORE: 11 Things We Remember About the 2015 Hurricane Season)
With only 11 named storms in the 2015 Atlantic season, it marked the first time in 21 years to have two consecutive below-average named storm seasons, according to Klotzbach.
So, let's take a look at past hurricane seasons following strong El Niños to see if we can gain any insight.
Past Post-Strong El Niño Atlantic Seasons
Using the El Niño intensity classification scheme from consultant meteorologist Jan Null, we examined five previous hurricane seasons following strong El Niños. The statistics from each of those seasons is below.
| Named Storms | Hurricanes | Cat. 3+ Hurricanes | U.S. Hurricane Landfalls | |
|---|---|---|---|---|
| 1998 | 14 | 10 | 3 | 3 |
| 1983 | 4 | 3 | 1 | 1 |
| 1973 | 8 | 4 | 1 | 0 |
| 1966 | 11 | 7 | 3 | 2 |
| 1958 | 10 | 7 | 5 | 0 |
As you can see, there's quite a spread, ranging from a record low four named storms in 1983 to 14 such storms in 1998.
The 1998 season featured seven U.S. landfalling tropical cyclones, three of which - Bonnie, Earl, and Georges - were hurricanes at landfall.
Despite only four named storms in 1983, two of those made U.S. landfall, including Category 3 Hurricane Alicia in southeast Texas.
This again illustrates the poor correlation between the number of named storms or hurricanes and landfalls.
In all, there have been a total of six U.S. hurricane landfalls in the five post-strong El Niño seasons dating to 1958, for an average of roughly one a season. Two of those five seasons were without a U.S. hurricane landfall, however.
What It Means in 2016
Klotzbach found that the chance of a U.S. hurricane impact rises dramatically in a La Niña or neutral (neither El Niño or La Niña) season compared to an El Niño season.
The U.S. averages between 1 to 2 hurricane landfalls each season, according to NOAA's Hurricane Research Division statistics.
(MORE: Hurricane Central)
As you may be aware, Florida has had an extraordinary run of over 10 years since its last hurricane impact (Hurricane Wilma in 2005), the longest hurricane-free streak for the Sunshine State in records dating to 1851.
(MORE: Florida Hurricane Drought Continues)
Furthermore, Wilma was the last Category 3 or stronger hurricane to landfall anywhere along the U.S. mainland, also the longest such streak dating to the mid-19th century.
We're past due.
Without El Niño contributing to stronger wind shear and dry air in the Caribbean Sea, it at least loads the dice toward an increased chance of tropical cyclones surviving into the Caribbean Sea, or forming there in 2016, particularly later in the season as El Niño disappears farther in the rear-view mirror.
If El Niño was the only factor, that is.
The previous two Atlantic hurricane seasons featured either few named storms (2014; 8) or a greater number of storms, but few of which survived long or became hurricanes (2013).
Each featured prohibitive dry air and/or wind shear during a significant part of the season, but El Niño was nowhere to be found.
(MORE: Facts and Myths About El Niño's Atlantic Hurricane Season Impacts)
To sum it up, the odds may shift a bit toward a more active Atlantic hurricane season in 2016, but El Niño's absence doesn't guarantee that outcome.
Nor does it mean it poses any greater threat to the U.S. compared to any other year.
All it takes is one intense, landfalling hurricane to render much of this El Niño talk moot. Prepare for every hurricane season, regardless of El Niño or its pre-season demise.
MORE ON WEATHER.COM: Hurricane Joaquin (Oct. 2015)
