MIAMI, Florida – NOAA’s National Hurricane Center issued a Tropical Weather Outlook at 2 a.m. Eastern Daylight Time on Saturday, September 21, 2019, due to the presence of three systems that may become tropical cyclones in addition to Tropical Storm Jerry.
The first system, named Invest 99L, is a tropical wave located several hundred miles east of the Windward Islands that is producing a large area of disorganized showers and thunderstorms (marked with an orange “X”).
Invest 99L is expected to move quickly westward at about 15 to 20 mph during the next few days.
NHC forecasters say that a tropical depression could form on Sunday or early next week while the system crosses the Windward Islands.
Upper-level winds are forecast to become less conducive for development by the middle of next week once Invest 99L moves out of the northeastern Caribbean Sea.
A NOAA Hurricane Hunter aircraft is scheduled to investigate this system this afternoon, if necessary.
Regardless of development, heavy rainfall is possible over much of the Lesser Antilles over the weekend, and interests on those islands and Puerto Rico should monitor the progress of this disturbance.
Invest 99L has a 50% chance of tropical cyclone formation within the next five days and a 40% chance within the next 48 hours.
The second system is a broad area of low pressure located just south of Haiti that continues to produce only disorganized showers and thunderstorms (marked with a yellow “X”).
Due to strong upper-level winds, significant development of this system is not expected while it moves slowly west-northwestward during the next couple of days.
Regardless of development, locally heavy rainfall is likely over portions of Hispaniola, Jamaica, and Cuba through the weekend, potentially causing flash flooding and mudslides in areas of high terrain.
This second system has a 10% chance of tropical cyclone formation within the next five days and a 10% chance within the next 48 hours.
The third system is a tropical wave forecast to move off the west coast of Africa by Sunday (marked with the red “X”).
According to the National Hurricane Center, environmental conditions are expected to be conducive for development thereafter while the system moves westward over the far eastern tropical Atlantic.
A tropical depression or tropical storm could form by early next week.
This system has a 90% chance of tropical cyclone formation within the next five days and a 30% chance within the next 48 hours.
If any of these systems becomes a tropical storm, the next name on the 2019 Atlantic Hurricane names list is Tropical Storm Karen.
Although peak hurricane season was on September 10, the weeks before and after peak hurricane season can be very active according to NOAA and the National Weather Service’s historical hurricane activity data.