May 30 (UPI) -- After two years of above average activity, forecasters say the 2019 Atlantic Hurricane season -- which begins Saturday -- will be pretty close to normal with about a dozen named storms.
The 2017 season was particularly brutal -- with Hurricanes Harvey, Irma and Maria inflicting billions of dollars worth of damage to the Caribbean and U.S. Gulf Coast. Forecasters say they don't expect 2019 to be as severe.
The National Oceanic and Atmospheric Administration's Climate Prediction Center issued its forecast last week. Covering the period between June 1 and Nov. 30, it says conditions and storms this season will most likely be close to normal for the North Atlantic Ocean, Caribbean Sea and Gulf of Mexico.
"A near-normal season has the highest chance of occurring (40 percent)," it said. The next greatest likelihood, however, is for an above-normal season, at 30 percent.
Near-normal calls for 10 to 15 named storms (a median of 12.5), of which one to four become major hurricanes -- those rated at Category 3 or stronger. Above-normal calls for between 12 and 28 named storms, and three to seven in the Category 3-5 range.
The outlook from Colorado State University's Tropical Meteorology Project, one of the United States' top forecast teams, calls for a similar season -- 13 named storms and five hurricanes, two of which will be in the "major" range.
Although both outlooks indicate an average season, that doesn't mean "normal" is without danger. Last year, considered relatively normal, included Hurricane Michael -- which hit the Florida Panhandle as a Category 5 storm. It caused about $25 billion in damage and killed dozens of people.
Harvey was a Category 4 storm when it hit Texas; Irma arrived in Florida at Category 3; and Maria hit Puerto Rico at Category 4 -- and the island still hasn't fully recovered from the storm.
The expectation of a milder season, the CSU team said, is largely based on the presence of a weak El Niño in the tropical Pacific, which tends to weaken hurricanes before they can build up too much strength. Researcher Jhordanne Jones said the El Niño is forecast to strengthen over time, which would help keep major hurricanes away from U.S. coastlines.
"We tend to have way less hurricanes in the North Atlantic when we have stronger El Niños," she said. "If the El Niño remains weak, then there's a greater potential for hurricanes to form.
"We can still get intense storms, no matter what El Niño state we have," she cautioned. "But it's not likely to be as strong as an Eastern Pacific El Niño."
Colder-than-average temperatures in the tropical Atlantic right now also make it less likely tropical cyclones will gain steam and develop into hurricanes. That could change, however, as the weather gets warmer.
"It's actually pretty cold within the tropical North Atlantic, but it remains to be seen how much warmer it gets as we move into summer," Jones said. "If it does get warmer, then we will likely see more intense storms."
The El Niño pattern and the atmosphere of the North Atlantic are most likely to determine the outcome of the 2019 hurricane season, she said.
By contrast, the harsh 2017 season -- which produced 18 named storms and 10 hurricanes, six of which were classified "major" -- arrived during La Niña and neutral conditions and inflicted nearly $300 billion in damage. The last major El Niño event was in 2016.
"It was a very slow buildup," Jones said. "We were basically in this neutral El Niño state for a really long time."
She added the presence of an El Niño, even if it remains weak, will differentiate the 2019 season from the previous two.
"We're likely to see probably the same sort of activity as the 2018 hurricane season, but with a larger El Niño event we're also likely to see less activity."
The El Niño-Southern Oscillation has greatly influenced the last few hurricane seasons and contributed to increased activity and the stronger storms of the past two years.
The team's research predicted a 48 percent chance a major hurricane will hit the United States this year. If one does arrive, the forecasters say there's a 28 percent likelihood the Category 3 to 5 storm will hit somewhere on the East Coast or Florida Peninsula; 28 percent it will hit the Gulf Coast; and 39 percent it will make landfall in the Caribbean. All figures are below the 100-year average.
Traditionally, the results of the Atlantic hurricane season closely reflect preseason predictions, but the CSU team warns that just one powerful storm can change everything.
"There's definitely a lot of factors that determine how active or inactive an average season is, but that doesn't necessarily change the level of damage, as only one storm can cause a lot of damage," she said.
The first named storm, subtropical storm Andrea, formed May 20 between the Bahamas and Bermuda. Relatively weak, it dissipated two days later.2019 Atlantic Hurricane Season Storm Names