An area of disturbed weather east of the Caribbean will likely grow into Hurricane Matthew according to the latest data from both American (GFS) and European (ECMWF) forecast model data.
Showers and thunderstorms associated with a broad area of low pressure located about 700 miles east-southeast of the Windward Islands are gradually becoming better organized. Environmental conditions remain conducive for development, and a tropical depression is likely to form during the next day or two while the system moves westward to west-northwestward near 20 mph.
The well-organized Tropical Wave, now known simply as #97L, lacks a closed circulation this morning, but Hurricane Hunter aircraft is scheduled to investigate the system later today to see if that has changed. Once the system has a closed center of circulation, it’ll be classified as a Tropical Depression. Once sustained winds at the surface reach 39mph, the system will be classified as a Tropical Storm. At that point it would be named, with Matthew being the next name on the list of 2016 Atlantic Basin Hurricane Names. Once Matthew gets winds sustained in excess of 74mph, it would be classified as a hurricane.
Interests in the eastern and central Caribbean Sea, including the northern coast of South America, should monitor the progress of this system. Regardless of development, heavy rains and strong gusty winds, possibly to tropical storm force, are expected to spread over the Windward Islands and portions of the southern Lesser Antilles beginning late Tuesday or Wednesday.
It is still far too soon to know what if any impacts Matthew would make on the US. Right now, odds favor an East Coast impact versus a Gulf of Mexico one, with the Mid Atlantic and Northeast more likely to see impacts than the Southeast. There are still chances that this system will head out to sea and miss the US entirely, but odds favor that there will be some kind of direct or indirect impacts to the East Coast over none at all.
You can get more specifics on this storm as well as any other storm, present or recent past, on our Hurricane & Tropical Weather Page here: https://weatherboy.com/hurricanes-tropical-weather/