A tropical wave racing toward the Caribbean and expected to spin into a potentially dangerous storm will likely reach the Windward Islands by Wednesday.
At 4:20 p.m. Tuesday, National Hurricane Center forecasters said the system was located about 300 miles east, southeast of Barbados and continuing to show signs of strengthening. A hurricane hunter plane sent to investigate the storm found the system had not yet closed into a loop, but was pounding out winds close to tropical storm force.
The storm continued to move west-northwestward at 15 to 20 mph.
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While no advisory was issued, forecasters said residents in the islands, including the Leeward Islands, along with the north coast of South America, should start watching the storm. Squally weather with heavy rain and tropical storm force winds could hit parts of the Windward Islands and southern Leeward Islands by tonight and continue through Wednesday.
Mild wind shear and very warm ocean water — temperatures hovered around 85 degrees — are expected to add muscle to the system, with some models predicting a quick intensification.
If the storm strengthens quickly, that could leave little time to prepare in a region where mountainous islands are vulnerable to flash-flooding and dangerous mudslides. Flooding in February in Haiti killed one person and damaged 10,000 homes. Another four people went missing.
Tuesday afternoon, authorities in Haiti tweeted a warning to expect heavy afternoon rain. The wave will also likely spread rain and thunderstorms across the south side of Hispaniola through the end of the week, hurricane center forecasters said..
Computer models largely agree on the storm’s track over the next few days, showing the storm pushing over the southern end of the islands and threading the needle between the coast of South America and Hispaniola. However, several turn the storm north across Haiti after about four days.
Whether the storm turns and slams the country depends on how intense it becomes, University of Miami hurricane researcher Brian McNoldy said.
“Really this is going to come down to how strong is the storm at that point. That will affect the layer of atmosphere that steers it. If it’s stronger, it’s going to turn more quickly to the north,” he said.
If the storm does track across Haiti, it could mimic the path of Hurricane Hazel, a brutal storm that plowed across the country in 1954, killing 400 people. When it struck the U.S., the storm had grown to a fierce Category 4, killing another 95.
“That storm did almost exactly what this storm is forecast to do,” he said.
Models are less reliable more than three to five days out, so how the storm impacts Haiti and the U.S. is still unclear.
“At this point for sure people in Florida and along the East Coast should be paying attention but not be hanging on every model run,” he said.
If the system becomes a named storm, it would be the 13th this year during the peak of the season, a time that historically has produced some of the basin’s strongest hurricanes.
Staff writer Jacqueline Charles contributed to this report.
Follow Jenny Staletovich on Twitter @jenstaletovich