Meteorologists with the National Oceanic and Atmospheric Administration think as many as 16 named tropical storms could form in the Atlantic Basin—which includes the Gulf of Mexico, Caribbean Sea and Atlantic Ocean—during the 2016 hurricane season, which begins June 1.
A summer that produced 16 named storms would be well above the dozen storms that form during an average season and would be considered an active summer. But shifting weather patterns and uncertainties about water temperatures in the Atlantic Basin prompted NOAA forecasters to note that conditions for hurricane formation may not be favorable—especially during the early part of the season—and said that as few as 10 named storms may form.
That would make 2016 a below average season.
NOAA’s forecasters think the season’s tropical storms could produce four to eight hurricanes with winds of at least 74 mph. And they think one to four of those storms could intensify into major hurricanes with winds exceeding 110 mph.
In a similar preseason forecast released in April, meteorologists at Colorado State University predicted that 12 named tropical storms would form, and that those storms would produce five hurricanes and two major hurricanes.
NOAA forecasters released their prediction as a developing weather system near the Bahamas appeared likely to strengthen into a tropical storm during the upcoming Memorial Day weekend. If the system’s winds reach 39 mph, it would become Tropical Storm Bonnie, the second storm of 2016.
Hurricane Alex, an unusual January hurricane, formed in the Atlantic earlier this year.
Three key factors could determine how active the approaching season will be.
A meteorological phenomenon known as El Niño that has strongly influenced weather since last year is expected to weaken. When El Niño’s influence was at its peak, it made conditions less favorable for hurricane formation in the Atlantic. If the phenomenon dissipates later this year, it could mean that conditions are more favorable for hurricane formation.
But scientists have noted indications that water temperatures in the Atlantic might be cooling, and this could make it more difficult for tropical storms to form. Hurricanes draw their strength from ocean waters heated to at least 80 degrees Fahrenheit.
Ocean temperatures are cyclical and can last for decades. The Atlantic Basin has been in a warming cycle since 1995, but NOAA Administrator Kathryn Sullivan said scientists have noted cooler temperatures in the Atlantic for the past three seasons.
Still, it’s too early to tell whether the Atlantic is entering a cooling cycle, Sullivan said.
The factor that could ultimately decide the summer’s hurricane activity is whether a weather phenomenon known as La Niña appears later this year. A La Niña could create more favorable conditions for hurricane formation in the Atlantic, especially if it appears during the peak of the storm season from August to October.
NOAA meteorologists said they could not predict whether the unusual streak of summers without a major hurricane making landfall in the U.S. would continue. The last major hurricane to strike the U.S. was 2005, when Hurricane Wilma pummeled the Florida Keys.
NOAA forecaster Gerry Bell said low-pressure systems over the eastern U.S. had helped steer hurricanes away from the Gulf and Atlantic coasts, but he could not predict whether such systems would come into play this summer.
The 2016 hurricane season will extend through November 30.