Forecasters are weighing in on the chances of an El Niño event developing later this year, with some assigning probabilities as high as 65 percent.
But what exactly does that mean for U.S. property insurers? How may hurricanes will there be?
While no one knows the answer for sure, two insurance industry research analysts compiled some historical figures based on their review of hurricane statistics for the period extending from 1951 to 2013.
Alan Zimmermann and William Wilt of Assured Research matched up El Niño years recorded by the National Weather Service with hurricane numbers from Unisys Weather, finding that for the 14 El Niño years in the 63-year span, between 3.0 and 4.6 hurricanes occurred on average.
More specifically, 4.6 was the figure corresponding to the nine years with “moderate” El Niños, with individual year totals ranging from three to eight, they reported in an April 14 research note.
For five years with “strong” El Niños, the average figure of three corresponds to a range extending from a low of two to a high of four.
For the years when there was no El Niño or where the event was “weak,” hurricanes totals averaged 6.8, according to Zimmermann and Wilt’s calculations.
Last month, during a March 18 webinar, Meteorologist Ray Hawthorne, who is also Product Manager for Insurance Products at WSI Corporation (a member of The Weather Company), said the location and intensity of the El Niño are critical factors in determining the ultimate impacts on storm developments.
If it forms into the eastern part of the Pacific Ocean—just off the South American coastline—rather than farther West in the Central Pacific, “that would really cap the number of storms this year [and] cause below-average activity in parts of the Atlantic basin,” he said.
El Niño warming changes the location of the jet stream, usually moving it farther South. “That actually tends to limit the amount of severe weather in the favorite areas of Tornado Alley. But it can increase the amount of severe weather in Florida and the Southeastern U.S.— but that’s typically later on in the year,” he said.
“Also, El Niño can actually reduce the number and intensity of hurricanes in the Atlantic,” he added.