Even as Tropical Storm Erika weakened slightly Tuesday, National Hurricane Center forecasters warned that South Florida could feel the effects of the fast-moving storm by the weekend.
Erika, which formed on the heels of Hurricane Danny on Monday in the middle of the Atlantic, intensified to a tropical storm with 45 mph winds late Monday before wobbling in the afternoon as it encountered dry air. At 11 p.m. Tuesday, sustained winds reached about 40 mph as Erika continued moving west, northwest at 18 mph about 495 miles east of Antigua.
Erika will likely regain strength steadily is it moves across the Caribbean, forecasters said, unleashing tropical storm force winds on the Leeward Islands by late Wednesday or early Thursday.
What happens next remains less certain, forecasters say, because models used to calculate hurricane tracks have split on what path Erika takes. While some predict a stronger storm will tack to the north, others point to a weaker storm headed more to the south. The storm could weaken as it moves over land or encounters dry conditions that helped snuff Danny.
“We don’t even have a hurricane until Sunday afternoon, and there’s a great deal of uncertainty about that, so the best thing for South Florida residents to do is check back every day or so,” said hurricane center spokesman and meteorologist Dennis Feltgen.
Erika arrives just as the hurricane season enters its peak months and comes ahead of a wave of weather washing off the coast of Africa. So far, both Danny and Erika have been influenced by dry air that worsened a deepening drought in some parts of the region. Puerto Rico is in the midst of record-breaking conditions that could be improved with rain from what’s left of Danny. But heavy rain forecast to fall on Haiti through Wednesday afternoon has also raised concerns about mudslides.
As Erika moves through the northeast Caribbean late Wednesday, forecasters say it will likely follow in Danny’s footsteps across the Virgin Islands and into Puerto Rico Thursday night and Friday.
Over the next five days, forecasters predict Erika will gradually strengthen but barely muster hurricane strength Sunday as it passes over the Bahamas.
"We are preparing accordingly as if we are going to be impacted between now and Saturday," said Captain Stephen Russell, head of the Bahamas National Emergency Management Agency. Residents, he said, are being warned to make every effort to "safeguard their property and their lives."
Unlike Danny, a compact storm able to quickly intensify and just as quickly lose strength, forecasters say Erika will take longer to build. On Thursday, as the storm nears Puerto Rico, they say winds could reach 60 mph. By Sunday afternoon, winds could increase to 75 mph, just qualifying Erika as a hurricane.
“It’s not quite what Danny was last week. There’s still not any environmental conditions for any big strengthening, so that’s why we have a slow, steady strengthening in the next five days,” Feltgen said. “We don’t see any rapid intensification from this.”
Feltgen said models differed on Erika’s forecast because they use different information, leaving it up to hurricane center forecasters to rely on their own expertise to project risks.
“What really comes into play is the skill and expertise of the hurricane specialists. They’ve been looking at this stuff for years,” he said. “Another thing to keep in mind —and this goes back to the 2004 season — please don’t pay attention to the skinny black line in the cone because the center of the storm can be anywhere in that cone.”
A big if in Erika’s track is a system forming off the U.S.’s Southeast coast. If the system steers Erika to the north, the eastern seaboard, Bermuda and Canada could be at risk. But if the storm remains weak, it will likely head to the south where it could run into Hispaniola and fall apart.
As of 11 p.m. Tuesday, a tropical storm warning was issued for Anguilla, Saba, St. Eustatius and St. Maarten. A warning means that tropical storm conditions are expected somewhere in the area within 36 hours.
Also late Tuesday, a tropical storm watch was issued for Puerto Rico, the U.S. Virgin Islands and the British Virgin Islands. A watch means tropical storm force winds are possible within 48 hours.
A tropical storm watch remained in effect for much of the Lesser Antilles, including Montserrat, Antigua, Barbuda, St. Kitts, Nevis, Guadeloupe, St. Martin and St. Barthelemy.
Staff writer Jacqueline Charles contributed to this report.