2018 Atlantic hurricane season: Is Puerto Rico at risk for another devastating blow?

By Jillian MacMath, AccuWeather staff writer

May 29, 2018, 1:22:32 PM EDT

Following a devastating blow to Puerto Rico during the 2017 Atlantic hurricane season, forecasters are keeping their eyes on the U.S. territory in case of another life-threatening impact this year.

Atlantic hurricane season officially begins on June 1, though the most likely time for the island to experience tropical impacts spans from the last week of August to the first week of September.

In 2017, Hurricane Maria struck within this time frame, resulting in the second-biggest blackout in the history of power on Earth and a huge number of fatalities.

Official figures suggested fewer than 100 people died as a result of the hurricane; however, estimates factoring in indirect deaths climbed to over 1,000 by other agencies in the following months.

A new study published on May 29 by researchers from Harvard University's T.H. Chan School of Public Health puts the death toll estimate even higher. According to the study, as many as 4,645 "excess deaths" may have occurred as a result of the storm between Sept. 20 and Dec. 31, 2017. 

President Donald Trump walks with FEMA administrator Brock Long, second from right, and Lt. Gen. Jeff Buchanan, right as he tours an area affected by Hurricane Maria in Guaynabo, Puerto Rico, Tuesday, Oct. 3, 2017. (AP Photo/Evan Vucci)

While Puerto Rico continues to pick up the pieces and rebuild its outdated power grid, many fear another impact could have catastrophic consequences.

While it is impossible to say for certain what will transpire this season, forecasters say a direct hit is unlikely.

AccuWeather Atlantic Hurricane Expert Dan Kottlowski said, “Statistically it would be unusual for Puerto Rico or the Virgin Islands to have direct impacts from a tropical storm or hurricane in back-to-back years.“

The last time this happened was in 1931 and 1932.

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Before Maria, the last direct hit to Puerto Rico was back in 2011, when an intensifying Hurricane Irene crossed the northeastern part of the Island inflicting heavy rainfall and hurricane-force wind gusts.

This year, the more likely scenario would be for Puerto Rico to experience impacts from a tropical storm or hurricane, rather than sustain a direct hit.

According to data, this occurs every three to four years.

AccuWeather’s official 2018 hurricane forecast calls for 12-15 storms in the Atlantic basin overall, six to eight of which are forecast to be hurricanes and three to five of which may be major hurricanes.

“This hasn’t changed since our official release in early April,” Kottlowski said. 

According to the outlook, sea surface temperatures are cooler than normal across the main developmental region where around 85 percent of all tropical storms and hurricanes originate.

He added, “If these cooler sea surface temperatures last into and through the summer, tropical development would favor the lower number values.”

Last year, the area was cooler than normal initially, before warming to above normal by Sept. 1.

Kottlowski said, “Preseason and early-season sea surface temperatures often don’t stay cool unless trade winds remain higher than normal,” as strong trade winds tend to result in cooler sea surface temperatures.

“Last year, the trade winds died down and ocean waters warmed up,” he said.

(Photo/NASA Earth Observatory Joshua Stevens)

Current computer models, which forecasters use to predict these changes, are mixed on the strength of the trades for August, September and October.

“We hope to see some trend by early July which should help give us more confidence,” Kottlowski said.

Despite this uncertainty, a direct hit remains statistically unlikely.

Kottlowski said, “This far out it is impossible to know how future tropical storms and hurricanes are going to track.”

“We may see some signal by early July, but it would be rare for the Virgin Islands and Puerto Rico to experience another high impact storm this year.”