FORT LAUDERDALE, Fla. – Tropical Storm Emily likely will spin into a hurricane by today and continue molding this unprecedented season into a remarkable stretch of hurricane history.

Emily is the fifth named storm to form in July, the first time that has happened since the U.S. began keeping storm records in 1851. Emily also stands to become the second major hurricane to develop this month, after Dennis, which struck near Pensacola on Sunday.

Late on Tuesday, Emily was in the Atlantic, 350 miles southeast of Barbabos, or about 1,950 miles southeast of Miami, churning west at 20 mph with sustained winds of 50 mph. Hurricane warnings have been issued for the Windward Islands, which face 3 to 6 inches of rain and coastal flooding.

The long range forecast takes the system south of the Dominican Republic on Friday, near Jamaica on Saturday and south of western Cuba on Sunday as a Category 3 system, packing 115 mph winds.

High pressure north of Emily might keep the system’s path south of Florida, said James Franklin, hurricane specialist with the National Hurricane Center in Miami-Dade County. But he said it’s too early to say for sure.

“At five days out, you hesitate to take anybody off the hook,” he said.

Why is this season so active so early?

Primarily, the atmosphere is abnormally calm with low wind shear, which can break storms apart, said Dave Roberts, a Navy meteorologist assigned to the hurricane center.

“You usually don’t see tropical waves turning into hurricanes in July,” he said. “That usually doesn’t happen until August.”

In addition, the Atlantic is significantly warmer than normal because of a natural cycle of warm water shifting to the tropical region, where hurricanes are spawned and nurtured. Scientists say that shift has resulted in an era of storm intensity that could last another 10 to 30 years.

Another factor: tropical waves, or blobs of low pressure that seed hurricanes, are very robust as they come off the coast of Africa, said Chris Landsea, a research meteorologist with the National Oceanic and Atmospheric Administration’s hurricane research division.

“There’s a lot of rotation to them, a lot of warm moisture being sucked in,” he said.

That both Dennis and Emily formed at low latitudes means “conditions already are conducive for hurricanes to form. That tells us it’s going to stay busy,” Landsea said.

Richard Pfeffer, a Florida State University professor and an expert in hurricane formation, said global warming shouldn’t be blamed for the storms’ early arrival.

“Records are set all the time,” he said. “With so many forming right now, I think we have to take it for what it is; conditions are ripe.”

Government forecasters predict seven to nine hurricanes this year, and Colorado State University prognosticator William Gray forecasts eight. Both projections might end up low if the season remains on its chaotic pace.

Dennis already has made this season unusual because it was one of only four major hurricanes to strike the U.S. coast in July since the early 1900s. July rarely sees one intense hurricane, let alone two. The only year where two formed in July was 1916. Prior to Dennis, the last major July hurricane hit just east of Pensacola on July 31, 1936.

Dennis was the fifth hurricane in a row to pummel Florida, after four storms struck the state last year. No state has ever been under such severe attack, officials said.

Based on historical averages, the fifth named storm doesn’t form until Sept. 7, meaning Emily has put this season almost two months ahead of schedule.

The season has more than four months to go, with the most active stretch normally running from mid August through September.

Despite its early start, Roberts, of the hurricane center, said it is possible the season could remain busy straight through October.

“It’s starting earlier than we expected but there’s no reason why it can’t continue,” he said.

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