The National Hurricane Center fell short of elevating a system 300 miles east of Barbados to cyclone status in a special advisory issued at 4:20 p.m., but said it could still become a tropical depression or tropical storm tonight or Wednesday.
The tropical wave, which has a 90 percent chance of developing over the next two days, is producing near tropical storm force winds, according to buoy data, and continued to show signs of organization.
But according to an Air Force Reserve reconnaissance mission, the system lacks a closed surface circulation.
Forecasters warned that the Windward and southern Leeward Islands, Bonaire, Curacao and Bermuda should watch the system closely.
“Regardless of whether the system is a tropical wave or a tropical cyclone, heavy rains and tropical storm-force winds in squalls are expected to spread over the Windward Islands and Portions of the southern Leeward Islands beginning tonight and continuing through Wednesday,” hurricane center forecasters said.
The system, which would be named Matthew if it gains tropical storm status, is expected to form up in waters south of Hispaniola, but where it goes from there is still tough to forecast.
Some early storm tracks show the system taking an abrupt right turn and heading north off the coast of Florida.
Jeff Masters, Weather Underground co-founder and former NOAA Hurricane Hunter, said while the sharp turn may seem implausible, there are a number of previous storms that have taken a similar track, especially in October.
“This sharp turn is expected to occur on Friday night or on Saturday, and the exact timing of the the turn has huge implications for who experiences the the peak wrath of the storm,” Masters wrote in an afternoon blog. “The models are quite bullish on this becoming a hurricane when it makes its landfall early next week in the islands.”
In a column for The Washington Post’s Capital Weather Gang, Angela Fritz and University of Miami’s Brian McNoldy say it’s too soon to mention specifics regarding landfall, “if there is a landfall at all.”
“But coastal residents along the Gulf and East coasts should be aware that there is the potential for a tropical storm or hurricane in their vicinity next week,” they wrote.
Previous story: The National Hurricane Center’s 8 a.m. advisory says the tropical wave being monitored about 475 miles east-southeast of Barbados could become a tropical cyclone over the next 24 hours.
If it gains named-status, it would be Matthew.
An Air Force Hurricane Hunter aircraft and crew is scheduled to investigate the system this afternoon, but as of this morning, forecasters said it lacked a closed center of circulation.
The system has a 90 percent chance of becoming a tropical cyclone over the next 48 hours.
“Regardless of whether the system is a tropical wave or tropical cyclone, heavy rains and wind gusts to tropical storm force are expected to spread over the Windward Islands and portions of the southern Lesser Antilles, beginning tonight and continuing into Wednesday,” center forecasters wrote.
While it is still uncertain where the system will go, forecast models show it taking a hard right turn south of Hispaniola and Cuba, and tracking north off the east coast of Florida.
“We have no idea where would-be Matthew will be going just yet,” said AccuWeather hurricane expert Dan Kottlowski. “The model output has been widespread, although the majority are taking it just to the east of the Bahamas right now.”
Jeff Masters, Weather Underground co-founder and former NOAA Hurricane Hunter, said the system could eventually make landfall anywhere from “Nicaragua to Newfoundland.”
“So we really can’t narrow things down much at this point,” Masters said in his blog.
But Kottlowski said until it’s a better organized system, it’s hard to say how the steering flow will affect it.
AccuWeather doesn’t believe the system will form up until later in the week because it’s northwestward traveling speed of 15 to 20 mph is too fast.